ExifInterface.java revision 473201868c0cb6d6fef4550c7aeb9c1ba7432d98
1/*
2 * Copyright (C) 2007 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package android.media;
18
19import android.annotation.NonNull;
20import android.content.res.AssetManager;
21import android.graphics.Bitmap;
22import android.graphics.BitmapFactory;
23import android.system.ErrnoException;
24import android.system.Os;
25import android.system.OsConstants;
26import android.util.Log;
27import android.util.Pair;
28import android.annotation.IntDef;
29
30import java.io.BufferedInputStream;
31import java.io.ByteArrayInputStream;
32import java.io.DataInputStream;
33import java.io.DataInput;
34import java.io.EOFException;
35import java.io.File;
36import java.io.FileDescriptor;
37import java.io.FileInputStream;
38import java.io.FileNotFoundException;
39import java.io.FileOutputStream;
40import java.io.FilterOutputStream;
41import java.io.IOException;
42import java.io.InputStream;
43import java.io.OutputStream;
44import java.nio.ByteBuffer;
45import java.nio.ByteOrder;
46import java.nio.charset.Charset;
47import java.nio.charset.StandardCharsets;
48import java.text.ParsePosition;
49import java.text.SimpleDateFormat;
50import java.util.Arrays;
51import java.util.LinkedList;
52import java.util.Date;
53import java.util.HashMap;
54import java.util.HashSet;
55import java.util.Map;
56import java.util.Set;
57import java.util.TimeZone;
58import java.util.regex.Matcher;
59import java.util.regex.Pattern;
60import java.lang.annotation.Retention;
61import java.lang.annotation.RetentionPolicy;
62
63import libcore.io.IoUtils;
64import libcore.io.Streams;
65
66/**
67 * This is a class for reading and writing Exif tags in a JPEG file or a RAW image file.
68 * <p>
69 * Supported formats are: JPEG, DNG, CR2, NEF, NRW, ARW, RW2, ORF, PEF, SRW and RAF.
70 * <p>
71 * Attribute mutation is supported for JPEG image files.
72 */
73public class ExifInterface {
74    private static final String TAG = "ExifInterface";
75    private static final boolean DEBUG = false;
76
77    // The Exif tag names. See Tiff 6.0 Section 3 and Section 8.
78    /** Type is String. */
79    public static final String TAG_ARTIST = "Artist";
80    /** Type is int. */
81    public static final String TAG_BITS_PER_SAMPLE = "BitsPerSample";
82    /** Type is int. */
83    public static final String TAG_COMPRESSION = "Compression";
84    /** Type is String. */
85    public static final String TAG_COPYRIGHT = "Copyright";
86    /** Type is String. */
87    public static final String TAG_DATETIME = "DateTime";
88    /** Type is String. */
89    public static final String TAG_IMAGE_DESCRIPTION = "ImageDescription";
90    /** Type is int. */
91    public static final String TAG_IMAGE_LENGTH = "ImageLength";
92    /** Type is int. */
93    public static final String TAG_IMAGE_WIDTH = "ImageWidth";
94    /** Type is int. */
95    public static final String TAG_JPEG_INTERCHANGE_FORMAT = "JPEGInterchangeFormat";
96    /** Type is int. */
97    public static final String TAG_JPEG_INTERCHANGE_FORMAT_LENGTH = "JPEGInterchangeFormatLength";
98    /** Type is String. */
99    public static final String TAG_MAKE = "Make";
100    /** Type is String. */
101    public static final String TAG_MODEL = "Model";
102    /** Type is int. */
103    public static final String TAG_ORIENTATION = "Orientation";
104    /** Type is int. */
105    public static final String TAG_PHOTOMETRIC_INTERPRETATION = "PhotometricInterpretation";
106    /** Type is int. */
107    public static final String TAG_PLANAR_CONFIGURATION = "PlanarConfiguration";
108    /** Type is rational. */
109    public static final String TAG_PRIMARY_CHROMATICITIES = "PrimaryChromaticities";
110    /** Type is rational. */
111    public static final String TAG_REFERENCE_BLACK_WHITE = "ReferenceBlackWhite";
112    /** Type is int. */
113    public static final String TAG_RESOLUTION_UNIT = "ResolutionUnit";
114    /** Type is int. */
115    public static final String TAG_ROWS_PER_STRIP = "RowsPerStrip";
116    /** Type is int. */
117    public static final String TAG_SAMPLES_PER_PIXEL = "SamplesPerPixel";
118    /** Type is String. */
119    public static final String TAG_SOFTWARE = "Software";
120    /** Type is int. */
121    public static final String TAG_STRIP_BYTE_COUNTS = "StripByteCounts";
122    /** Type is int. */
123    public static final String TAG_STRIP_OFFSETS = "StripOffsets";
124    /** Type is int. */
125    public static final String TAG_TRANSFER_FUNCTION = "TransferFunction";
126    /** Type is rational. */
127    public static final String TAG_WHITE_POINT = "WhitePoint";
128    /** Type is rational. */
129    public static final String TAG_X_RESOLUTION = "XResolution";
130    /** Type is rational. */
131    public static final String TAG_Y_CB_CR_COEFFICIENTS = "YCbCrCoefficients";
132    /** Type is int. */
133    public static final String TAG_Y_CB_CR_POSITIONING = "YCbCrPositioning";
134    /** Type is int. */
135    public static final String TAG_Y_CB_CR_SUB_SAMPLING = "YCbCrSubSampling";
136    /** Type is rational. */
137    public static final String TAG_Y_RESOLUTION = "YResolution";
138    /** Type is rational. */
139    public static final String TAG_APERTURE_VALUE = "ApertureValue";
140    /** Type is rational. */
141    public static final String TAG_BRIGHTNESS_VALUE = "BrightnessValue";
142    /** Type is String. */
143    public static final String TAG_CFA_PATTERN = "CFAPattern";
144    /** Type is int. */
145    public static final String TAG_COLOR_SPACE = "ColorSpace";
146    /** Type is String. */
147    public static final String TAG_COMPONENTS_CONFIGURATION = "ComponentsConfiguration";
148    /** Type is rational. */
149    public static final String TAG_COMPRESSED_BITS_PER_PIXEL = "CompressedBitsPerPixel";
150    /** Type is int. */
151    public static final String TAG_CONTRAST = "Contrast";
152    /** Type is int. */
153    public static final String TAG_CUSTOM_RENDERED = "CustomRendered";
154    /** Type is String. */
155    public static final String TAG_DATETIME_DIGITIZED = "DateTimeDigitized";
156    /** Type is String. */
157    public static final String TAG_DATETIME_ORIGINAL = "DateTimeOriginal";
158    /** Type is String. */
159    public static final String TAG_DEVICE_SETTING_DESCRIPTION = "DeviceSettingDescription";
160    /** Type is double. */
161    public static final String TAG_DIGITAL_ZOOM_RATIO = "DigitalZoomRatio";
162    /** Type is String. */
163    public static final String TAG_EXIF_VERSION = "ExifVersion";
164    /** Type is double. */
165    public static final String TAG_EXPOSURE_BIAS_VALUE = "ExposureBiasValue";
166    /** Type is rational. */
167    public static final String TAG_EXPOSURE_INDEX = "ExposureIndex";
168    /** Type is int. */
169    public static final String TAG_EXPOSURE_MODE = "ExposureMode";
170    /** Type is int. */
171    public static final String TAG_EXPOSURE_PROGRAM = "ExposureProgram";
172    /** Type is double. */
173    public static final String TAG_EXPOSURE_TIME = "ExposureTime";
174    /** Type is double. */
175    public static final String TAG_F_NUMBER = "FNumber";
176    /**
177     * Type is double.
178     *
179     * @deprecated use {@link #TAG_F_NUMBER} instead
180     */
181    @Deprecated
182    public static final String TAG_APERTURE = "FNumber";
183    /** Type is String. */
184    public static final String TAG_FILE_SOURCE = "FileSource";
185    /** Type is int. */
186    public static final String TAG_FLASH = "Flash";
187    /** Type is rational. */
188    public static final String TAG_FLASH_ENERGY = "FlashEnergy";
189    /** Type is String. */
190    public static final String TAG_FLASHPIX_VERSION = "FlashpixVersion";
191    /** Type is rational. */
192    public static final String TAG_FOCAL_LENGTH = "FocalLength";
193    /** Type is int. */
194    public static final String TAG_FOCAL_LENGTH_IN_35MM_FILM = "FocalLengthIn35mmFilm";
195    /** Type is int. */
196    public static final String TAG_FOCAL_PLANE_RESOLUTION_UNIT = "FocalPlaneResolutionUnit";
197    /** Type is rational. */
198    public static final String TAG_FOCAL_PLANE_X_RESOLUTION = "FocalPlaneXResolution";
199    /** Type is rational. */
200    public static final String TAG_FOCAL_PLANE_Y_RESOLUTION = "FocalPlaneYResolution";
201    /** Type is int. */
202    public static final String TAG_GAIN_CONTROL = "GainControl";
203    /** Type is int. */
204    public static final String TAG_ISO_SPEED_RATINGS = "ISOSpeedRatings";
205    /**
206     * Type is int.
207     *
208     * @deprecated use {@link #TAG_ISO_SPEED_RATINGS} instead
209     */
210    @Deprecated
211    public static final String TAG_ISO = "ISOSpeedRatings";
212    /** Type is String. */
213    public static final String TAG_IMAGE_UNIQUE_ID = "ImageUniqueID";
214    /** Type is int. */
215    public static final String TAG_LIGHT_SOURCE = "LightSource";
216    /** Type is String. */
217    public static final String TAG_MAKER_NOTE = "MakerNote";
218    /** Type is rational. */
219    public static final String TAG_MAX_APERTURE_VALUE = "MaxApertureValue";
220    /** Type is int. */
221    public static final String TAG_METERING_MODE = "MeteringMode";
222    /** Type is int. */
223    public static final String TAG_NEW_SUBFILE_TYPE = "NewSubfileType";
224    /** Type is String. */
225    public static final String TAG_OECF = "OECF";
226    /** Type is int. */
227    public static final String TAG_PIXEL_X_DIMENSION = "PixelXDimension";
228    /** Type is int. */
229    public static final String TAG_PIXEL_Y_DIMENSION = "PixelYDimension";
230    /** Type is String. */
231    public static final String TAG_RELATED_SOUND_FILE = "RelatedSoundFile";
232    /** Type is int. */
233    public static final String TAG_SATURATION = "Saturation";
234    /** Type is int. */
235    public static final String TAG_SCENE_CAPTURE_TYPE = "SceneCaptureType";
236    /** Type is String. */
237    public static final String TAG_SCENE_TYPE = "SceneType";
238    /** Type is int. */
239    public static final String TAG_SENSING_METHOD = "SensingMethod";
240    /** Type is int. */
241    public static final String TAG_SHARPNESS = "Sharpness";
242    /** Type is rational. */
243    public static final String TAG_SHUTTER_SPEED_VALUE = "ShutterSpeedValue";
244    /** Type is String. */
245    public static final String TAG_SPATIAL_FREQUENCY_RESPONSE = "SpatialFrequencyResponse";
246    /** Type is String. */
247    public static final String TAG_SPECTRAL_SENSITIVITY = "SpectralSensitivity";
248    /** Type is int. */
249    public static final String TAG_SUBFILE_TYPE = "SubfileType";
250    /** Type is String. */
251    public static final String TAG_SUBSEC_TIME = "SubSecTime";
252    /**
253     * Type is String.
254     *
255     * @deprecated use {@link #TAG_SUBSEC_TIME_DIGITIZED} instead
256     */
257    public static final String TAG_SUBSEC_TIME_DIG = "SubSecTimeDigitized";
258    /** Type is String. */
259    public static final String TAG_SUBSEC_TIME_DIGITIZED = "SubSecTimeDigitized";
260    /**
261     * Type is String.
262     *
263     * @deprecated use {@link #TAG_SUBSEC_TIME_ORIGINAL} instead
264     */
265    public static final String TAG_SUBSEC_TIME_ORIG = "SubSecTimeOriginal";
266    /** Type is String. */
267    public static final String TAG_SUBSEC_TIME_ORIGINAL = "SubSecTimeOriginal";
268    /** Type is int. */
269    public static final String TAG_SUBJECT_AREA = "SubjectArea";
270    /** Type is double. */
271    public static final String TAG_SUBJECT_DISTANCE = "SubjectDistance";
272    /** Type is int. */
273    public static final String TAG_SUBJECT_DISTANCE_RANGE = "SubjectDistanceRange";
274    /** Type is int. */
275    public static final String TAG_SUBJECT_LOCATION = "SubjectLocation";
276    /** Type is String. */
277    public static final String TAG_USER_COMMENT = "UserComment";
278    /** Type is int. */
279    public static final String TAG_WHITE_BALANCE = "WhiteBalance";
280    /**
281     * The altitude (in meters) based on the reference in TAG_GPS_ALTITUDE_REF.
282     * Type is rational.
283     */
284    public static final String TAG_GPS_ALTITUDE = "GPSAltitude";
285    /**
286     * 0 if the altitude is above sea level. 1 if the altitude is below sea
287     * level. Type is int.
288     */
289    public static final String TAG_GPS_ALTITUDE_REF = "GPSAltitudeRef";
290    /** Type is String. */
291    public static final String TAG_GPS_AREA_INFORMATION = "GPSAreaInformation";
292    /** Type is rational. */
293    public static final String TAG_GPS_DOP = "GPSDOP";
294    /** Type is String. */
295    public static final String TAG_GPS_DATESTAMP = "GPSDateStamp";
296    /** Type is rational. */
297    public static final String TAG_GPS_DEST_BEARING = "GPSDestBearing";
298    /** Type is String. */
299    public static final String TAG_GPS_DEST_BEARING_REF = "GPSDestBearingRef";
300    /** Type is rational. */
301    public static final String TAG_GPS_DEST_DISTANCE = "GPSDestDistance";
302    /** Type is String. */
303    public static final String TAG_GPS_DEST_DISTANCE_REF = "GPSDestDistanceRef";
304    /** Type is rational. */
305    public static final String TAG_GPS_DEST_LATITUDE = "GPSDestLatitude";
306    /** Type is String. */
307    public static final String TAG_GPS_DEST_LATITUDE_REF = "GPSDestLatitudeRef";
308    /** Type is rational. */
309    public static final String TAG_GPS_DEST_LONGITUDE = "GPSDestLongitude";
310    /** Type is String. */
311    public static final String TAG_GPS_DEST_LONGITUDE_REF = "GPSDestLongitudeRef";
312    /** Type is int. */
313    public static final String TAG_GPS_DIFFERENTIAL = "GPSDifferential";
314    /** Type is rational. */
315    public static final String TAG_GPS_IMG_DIRECTION = "GPSImgDirection";
316    /** Type is String. */
317    public static final String TAG_GPS_IMG_DIRECTION_REF = "GPSImgDirectionRef";
318    /** Type is rational. Format is "num1/denom1,num2/denom2,num3/denom3". */
319    public static final String TAG_GPS_LATITUDE = "GPSLatitude";
320    /** Type is String. */
321    public static final String TAG_GPS_LATITUDE_REF = "GPSLatitudeRef";
322    /** Type is rational. Format is "num1/denom1,num2/denom2,num3/denom3". */
323    public static final String TAG_GPS_LONGITUDE = "GPSLongitude";
324    /** Type is String. */
325    public static final String TAG_GPS_LONGITUDE_REF = "GPSLongitudeRef";
326    /** Type is String. */
327    public static final String TAG_GPS_MAP_DATUM = "GPSMapDatum";
328    /** Type is String. */
329    public static final String TAG_GPS_MEASURE_MODE = "GPSMeasureMode";
330    /** Type is String. Name of GPS processing method used for location finding. */
331    public static final String TAG_GPS_PROCESSING_METHOD = "GPSProcessingMethod";
332    /** Type is String. */
333    public static final String TAG_GPS_SATELLITES = "GPSSatellites";
334    /** Type is rational. */
335    public static final String TAG_GPS_SPEED = "GPSSpeed";
336    /** Type is String. */
337    public static final String TAG_GPS_SPEED_REF = "GPSSpeedRef";
338    /** Type is String. */
339    public static final String TAG_GPS_STATUS = "GPSStatus";
340    /** Type is String. Format is "hh:mm:ss". */
341    public static final String TAG_GPS_TIMESTAMP = "GPSTimeStamp";
342    /** Type is rational. */
343    public static final String TAG_GPS_TRACK = "GPSTrack";
344    /** Type is String. */
345    public static final String TAG_GPS_TRACK_REF = "GPSTrackRef";
346    /** Type is String. */
347    public static final String TAG_GPS_VERSION_ID = "GPSVersionID";
348    /** Type is String. */
349    public static final String TAG_INTEROPERABILITY_INDEX = "InteroperabilityIndex";
350    /** Type is int. */
351    public static final String TAG_THUMBNAIL_IMAGE_LENGTH = "ThumbnailImageLength";
352    /** Type is int. */
353    public static final String TAG_THUMBNAIL_IMAGE_WIDTH = "ThumbnailImageWidth";
354    /** Type is int. DNG Specification 1.4.0.0. Section 4 */
355    public static final String TAG_DNG_VERSION = "DNGVersion";
356    /** Type is int. DNG Specification 1.4.0.0. Section 4 */
357    public static final String TAG_DEFAULT_CROP_SIZE = "DefaultCropSize";
358    /** Type is undefined. See Olympus MakerNote tags in http://www.exiv2.org/tags-olympus.html. */
359    public static final String TAG_ORF_THUMBNAIL_IMAGE = "ThumbnailImage";
360    /** Type is int. See Olympus Camera Settings tags in http://www.exiv2.org/tags-olympus.html. */
361    public static final String TAG_ORF_PREVIEW_IMAGE_START = "PreviewImageStart";
362    /** Type is int. See Olympus Camera Settings tags in http://www.exiv2.org/tags-olympus.html. */
363    public static final String TAG_ORF_PREVIEW_IMAGE_LENGTH = "PreviewImageLength";
364    /** Type is int. See Olympus Image Processing tags in http://www.exiv2.org/tags-olympus.html. */
365    public static final String TAG_ORF_ASPECT_FRAME = "AspectFrame";
366    /**
367     * Type is int. See PanasonicRaw tags in
368     * http://www.sno.phy.queensu.ca/~phil/exiftool/TagNames/PanasonicRaw.html
369     */
370    public static final String TAG_RW2_SENSOR_BOTTOM_BORDER = "SensorBottomBorder";
371    /**
372     * Type is int. See PanasonicRaw tags in
373     * http://www.sno.phy.queensu.ca/~phil/exiftool/TagNames/PanasonicRaw.html
374     */
375    public static final String TAG_RW2_SENSOR_LEFT_BORDER = "SensorLeftBorder";
376    /**
377     * Type is int. See PanasonicRaw tags in
378     * http://www.sno.phy.queensu.ca/~phil/exiftool/TagNames/PanasonicRaw.html
379     */
380    public static final String TAG_RW2_SENSOR_RIGHT_BORDER = "SensorRightBorder";
381    /**
382     * Type is int. See PanasonicRaw tags in
383     * http://www.sno.phy.queensu.ca/~phil/exiftool/TagNames/PanasonicRaw.html
384     */
385    public static final String TAG_RW2_SENSOR_TOP_BORDER = "SensorTopBorder";
386    /**
387     * Type is int. See PanasonicRaw tags in
388     * http://www.sno.phy.queensu.ca/~phil/exiftool/TagNames/PanasonicRaw.html
389     */
390    public static final String TAG_RW2_ISO = "ISO";
391    /**
392     * Type is undefined. See PanasonicRaw tags in
393     * http://www.sno.phy.queensu.ca/~phil/exiftool/TagNames/PanasonicRaw.html
394     */
395    public static final String TAG_RW2_JPG_FROM_RAW = "JpgFromRaw";
396
397    /**
398     * Private tags used for pointing the other IFD offsets.
399     * The types of the following tags are int.
400     * See JEITA CP-3451C Section 4.6.3: Exif-specific IFD.
401     * For SubIFD, see Note 1 of Adobe PageMaker® 6.0 TIFF Technical Notes.
402     */
403    private static final String TAG_EXIF_IFD_POINTER = "ExifIFDPointer";
404    private static final String TAG_GPS_INFO_IFD_POINTER = "GPSInfoIFDPointer";
405    private static final String TAG_INTEROPERABILITY_IFD_POINTER = "InteroperabilityIFDPointer";
406    private static final String TAG_SUB_IFD_POINTER = "SubIFDPointer";
407    // Proprietary pointer tags used for ORF files.
408    // See http://www.exiv2.org/tags-olympus.html
409    private static final String TAG_ORF_CAMERA_SETTINGS_IFD_POINTER = "CameraSettingsIFDPointer";
410    private static final String TAG_ORF_IMAGE_PROCESSING_IFD_POINTER = "ImageProcessingIFDPointer";
411
412    // Private tags used for thumbnail information.
413    private static final String TAG_HAS_THUMBNAIL = "HasThumbnail";
414    private static final String TAG_THUMBNAIL_OFFSET = "ThumbnailOffset";
415    private static final String TAG_THUMBNAIL_LENGTH = "ThumbnailLength";
416    private static final String TAG_THUMBNAIL_DATA = "ThumbnailData";
417    private static final int MAX_THUMBNAIL_SIZE = 512;
418
419    // Constants used for the Orientation Exif tag.
420    public static final int ORIENTATION_UNDEFINED = 0;
421    public static final int ORIENTATION_NORMAL = 1;
422    public static final int ORIENTATION_FLIP_HORIZONTAL = 2;  // left right reversed mirror
423    public static final int ORIENTATION_ROTATE_180 = 3;
424    public static final int ORIENTATION_FLIP_VERTICAL = 4;  // upside down mirror
425    // flipped about top-left <--> bottom-right axis
426    public static final int ORIENTATION_TRANSPOSE = 5;
427    public static final int ORIENTATION_ROTATE_90 = 6;  // rotate 90 cw to right it
428    // flipped about top-right <--> bottom-left axis
429    public static final int ORIENTATION_TRANSVERSE = 7;
430    public static final int ORIENTATION_ROTATE_270 = 8;  // rotate 270 to right it
431
432    // Constants used for white balance
433    public static final int WHITEBALANCE_AUTO = 0;
434    public static final int WHITEBALANCE_MANUAL = 1;
435
436    // Maximum size for checking file type signature (see image_type_recognition_lite.cc)
437    private static final int SIGNATURE_CHECK_SIZE = 5000;
438
439    private static final byte[] JPEG_SIGNATURE = new byte[] {(byte) 0xff, (byte) 0xd8, (byte) 0xff};
440    private static final String RAF_SIGNATURE = "FUJIFILMCCD-RAW";
441    private static final int RAF_OFFSET_TO_JPEG_IMAGE_OFFSET = 84;
442    private static final int RAF_INFO_SIZE = 160;
443    private static final int RAF_JPEG_LENGTH_VALUE_SIZE = 4;
444
445    private static final byte[] HEIF_TYPE_FTYP = new byte[] {'f', 't', 'y', 'p'};
446    private static final byte[] HEIF_BRAND_MIF1 = new byte[] {'m', 'i', 'f', '1'};
447    private static final byte[] HEIF_BRAND_HEIC = new byte[] {'h', 'e', 'i', 'c'};
448
449    // See http://fileformats.archiveteam.org/wiki/Olympus_ORF
450    private static final short ORF_SIGNATURE_1 = 0x4f52;
451    private static final short ORF_SIGNATURE_2 = 0x5352;
452    // There are two formats for Olympus Makernote Headers. Each has different identifiers and
453    // offsets to the actual data.
454    // See http://www.exiv2.org/makernote.html#R1
455    private static final byte[] ORF_MAKER_NOTE_HEADER_1 = new byte[] {(byte) 0x4f, (byte) 0x4c,
456            (byte) 0x59, (byte) 0x4d, (byte) 0x50, (byte) 0x00}; // "OLYMP\0"
457    private static final byte[] ORF_MAKER_NOTE_HEADER_2 = new byte[] {(byte) 0x4f, (byte) 0x4c,
458            (byte) 0x59, (byte) 0x4d, (byte) 0x50, (byte) 0x55, (byte) 0x53, (byte) 0x00,
459            (byte) 0x49, (byte) 0x49}; // "OLYMPUS\0II"
460    private static final int ORF_MAKER_NOTE_HEADER_1_SIZE = 8;
461    private static final int ORF_MAKER_NOTE_HEADER_2_SIZE = 12;
462
463    // See http://fileformats.archiveteam.org/wiki/RW2
464    private static final short RW2_SIGNATURE = 0x0055;
465
466    // See http://fileformats.archiveteam.org/wiki/Pentax_PEF
467    private static final String PEF_SIGNATURE = "PENTAX";
468    // See http://www.exiv2.org/makernote.html#R11
469    private static final int PEF_MAKER_NOTE_SKIP_SIZE = 6;
470
471    private static SimpleDateFormat sFormatter;
472
473    // See Exchangeable image file format for digital still cameras: Exif version 2.2.
474    // The following values are for parsing EXIF data area. There are tag groups in EXIF data area.
475    // They are called "Image File Directory". They have multiple data formats to cover various
476    // image metadata from GPS longitude to camera model name.
477
478    // Types of Exif byte alignments (see JEITA CP-3451C Section 4.5.2)
479    private static final short BYTE_ALIGN_II = 0x4949;  // II: Intel order
480    private static final short BYTE_ALIGN_MM = 0x4d4d;  // MM: Motorola order
481
482    // TIFF Header Fixed Constant (see JEITA CP-3451C Section 4.5.2)
483    private static final byte START_CODE = 0x2a; // 42
484    private static final int IFD_OFFSET = 8;
485
486    // Formats for the value in IFD entry (See TIFF 6.0 Section 2, "Image File Directory".)
487    private static final int IFD_FORMAT_BYTE = 1;
488    private static final int IFD_FORMAT_STRING = 2;
489    private static final int IFD_FORMAT_USHORT = 3;
490    private static final int IFD_FORMAT_ULONG = 4;
491    private static final int IFD_FORMAT_URATIONAL = 5;
492    private static final int IFD_FORMAT_SBYTE = 6;
493    private static final int IFD_FORMAT_UNDEFINED = 7;
494    private static final int IFD_FORMAT_SSHORT = 8;
495    private static final int IFD_FORMAT_SLONG = 9;
496    private static final int IFD_FORMAT_SRATIONAL = 10;
497    private static final int IFD_FORMAT_SINGLE = 11;
498    private static final int IFD_FORMAT_DOUBLE = 12;
499    // Format indicating a new IFD entry (See Adobe PageMaker® 6.0 TIFF Technical Notes, "New Tag")
500    private static final int IFD_FORMAT_IFD = 13;
501    // Names for the data formats for debugging purpose.
502    private static final String[] IFD_FORMAT_NAMES = new String[] {
503            "", "BYTE", "STRING", "USHORT", "ULONG", "URATIONAL", "SBYTE", "UNDEFINED", "SSHORT",
504            "SLONG", "SRATIONAL", "SINGLE", "DOUBLE"
505    };
506    // Sizes of the components of each IFD value format
507    private static final int[] IFD_FORMAT_BYTES_PER_FORMAT = new int[] {
508            0, 1, 1, 2, 4, 8, 1, 1, 2, 4, 8, 4, 8, 1
509    };
510    private static final byte[] EXIF_ASCII_PREFIX = new byte[] {
511            0x41, 0x53, 0x43, 0x49, 0x49, 0x0, 0x0, 0x0
512    };
513
514    /**
515     * Constants used for Compression tag.
516     * For Value 1, 2, 32773, see TIFF 6.0 Spec Section 3: Bilevel Images, Compression
517     * For Value 6, see TIFF 6.0 Spec Section 22: JPEG Compression, Extensions to Existing Fields
518     * For Value 7, 8, 34892, see DNG Specification 1.4.0.0. Section 3, Compression
519     */
520    private static final int DATA_UNCOMPRESSED = 1;
521    private static final int DATA_HUFFMAN_COMPRESSED = 2;
522    private static final int DATA_JPEG = 6;
523    private static final int DATA_JPEG_COMPRESSED = 7;
524    private static final int DATA_DEFLATE_ZIP = 8;
525    private static final int DATA_PACK_BITS_COMPRESSED = 32773;
526    private static final int DATA_LOSSY_JPEG = 34892;
527
528    /**
529     * Constants used for BitsPerSample tag.
530     * For RGB, see TIFF 6.0 Spec Section 6, Differences from Palette Color Images
531     * For Greyscale, see TIFF 6.0 Spec Section 4, Differences from Bilevel Images
532     */
533    private static final int[] BITS_PER_SAMPLE_RGB = new int[] { 8, 8, 8 };
534    private static final int[] BITS_PER_SAMPLE_GREYSCALE_1 = new int[] { 4 };
535    private static final int[] BITS_PER_SAMPLE_GREYSCALE_2 = new int[] { 8 };
536
537    /**
538     * Constants used for PhotometricInterpretation tag.
539     * For White/Black, see Section 3, Color.
540     * See TIFF 6.0 Spec Section 22, Minimum Requirements for TIFF with JPEG Compression.
541     */
542    private static final int PHOTOMETRIC_INTERPRETATION_WHITE_IS_ZERO = 0;
543    private static final int PHOTOMETRIC_INTERPRETATION_BLACK_IS_ZERO = 1;
544    private static final int PHOTOMETRIC_INTERPRETATION_RGB = 2;
545    private static final int PHOTOMETRIC_INTERPRETATION_YCBCR = 6;
546
547    /**
548     * Constants used for NewSubfileType tag.
549     * See TIFF 6.0 Spec Section 8
550     * */
551    private static final int ORIGINAL_RESOLUTION_IMAGE = 0;
552    private static final int REDUCED_RESOLUTION_IMAGE = 1;
553
554    // A class for indicating EXIF rational type.
555    private static class Rational {
556        public final long numerator;
557        public final long denominator;
558
559        private Rational(long numerator, long denominator) {
560            // Handle erroneous case
561            if (denominator == 0) {
562                this.numerator = 0;
563                this.denominator = 1;
564                return;
565            }
566            this.numerator = numerator;
567            this.denominator = denominator;
568        }
569
570        @Override
571        public String toString() {
572            return numerator + "/" + denominator;
573        }
574
575        public double calculate() {
576            return (double) numerator / denominator;
577        }
578    }
579
580    // A class for indicating EXIF attribute.
581    private static class ExifAttribute {
582        public final int format;
583        public final int numberOfComponents;
584        public final byte[] bytes;
585
586        private ExifAttribute(int format, int numberOfComponents, byte[] bytes) {
587            this.format = format;
588            this.numberOfComponents = numberOfComponents;
589            this.bytes = bytes;
590        }
591
592        public static ExifAttribute createUShort(int[] values, ByteOrder byteOrder) {
593            final ByteBuffer buffer = ByteBuffer.wrap(
594                    new byte[IFD_FORMAT_BYTES_PER_FORMAT[IFD_FORMAT_USHORT] * values.length]);
595            buffer.order(byteOrder);
596            for (int value : values) {
597                buffer.putShort((short) value);
598            }
599            return new ExifAttribute(IFD_FORMAT_USHORT, values.length, buffer.array());
600        }
601
602        public static ExifAttribute createUShort(int value, ByteOrder byteOrder) {
603            return createUShort(new int[] {value}, byteOrder);
604        }
605
606        public static ExifAttribute createULong(long[] values, ByteOrder byteOrder) {
607            final ByteBuffer buffer = ByteBuffer.wrap(
608                    new byte[IFD_FORMAT_BYTES_PER_FORMAT[IFD_FORMAT_ULONG] * values.length]);
609            buffer.order(byteOrder);
610            for (long value : values) {
611                buffer.putInt((int) value);
612            }
613            return new ExifAttribute(IFD_FORMAT_ULONG, values.length, buffer.array());
614        }
615
616        public static ExifAttribute createULong(long value, ByteOrder byteOrder) {
617            return createULong(new long[] {value}, byteOrder);
618        }
619
620        public static ExifAttribute createSLong(int[] values, ByteOrder byteOrder) {
621            final ByteBuffer buffer = ByteBuffer.wrap(
622                    new byte[IFD_FORMAT_BYTES_PER_FORMAT[IFD_FORMAT_SLONG] * values.length]);
623            buffer.order(byteOrder);
624            for (int value : values) {
625                buffer.putInt(value);
626            }
627            return new ExifAttribute(IFD_FORMAT_SLONG, values.length, buffer.array());
628        }
629
630        public static ExifAttribute createSLong(int value, ByteOrder byteOrder) {
631            return createSLong(new int[] {value}, byteOrder);
632        }
633
634        public static ExifAttribute createByte(String value) {
635            // Exception for GPSAltitudeRef tag
636            if (value.length() == 1 && value.charAt(0) >= '0' && value.charAt(0) <= '1') {
637                final byte[] bytes = new byte[] { (byte) (value.charAt(0) - '0') };
638                return new ExifAttribute(IFD_FORMAT_BYTE, bytes.length, bytes);
639            }
640            final byte[] ascii = value.getBytes(ASCII);
641            return new ExifAttribute(IFD_FORMAT_BYTE, ascii.length, ascii);
642        }
643
644        public static ExifAttribute createString(String value) {
645            final byte[] ascii = (value + '\0').getBytes(ASCII);
646            return new ExifAttribute(IFD_FORMAT_STRING, ascii.length, ascii);
647        }
648
649        public static ExifAttribute createURational(Rational[] values, ByteOrder byteOrder) {
650            final ByteBuffer buffer = ByteBuffer.wrap(
651                    new byte[IFD_FORMAT_BYTES_PER_FORMAT[IFD_FORMAT_URATIONAL] * values.length]);
652            buffer.order(byteOrder);
653            for (Rational value : values) {
654                buffer.putInt((int) value.numerator);
655                buffer.putInt((int) value.denominator);
656            }
657            return new ExifAttribute(IFD_FORMAT_URATIONAL, values.length, buffer.array());
658        }
659
660        public static ExifAttribute createURational(Rational value, ByteOrder byteOrder) {
661            return createURational(new Rational[] {value}, byteOrder);
662        }
663
664        public static ExifAttribute createSRational(Rational[] values, ByteOrder byteOrder) {
665            final ByteBuffer buffer = ByteBuffer.wrap(
666                    new byte[IFD_FORMAT_BYTES_PER_FORMAT[IFD_FORMAT_SRATIONAL] * values.length]);
667            buffer.order(byteOrder);
668            for (Rational value : values) {
669                buffer.putInt((int) value.numerator);
670                buffer.putInt((int) value.denominator);
671            }
672            return new ExifAttribute(IFD_FORMAT_SRATIONAL, values.length, buffer.array());
673        }
674
675        public static ExifAttribute createSRational(Rational value, ByteOrder byteOrder) {
676            return createSRational(new Rational[] {value}, byteOrder);
677        }
678
679        public static ExifAttribute createDouble(double[] values, ByteOrder byteOrder) {
680            final ByteBuffer buffer = ByteBuffer.wrap(
681                    new byte[IFD_FORMAT_BYTES_PER_FORMAT[IFD_FORMAT_DOUBLE] * values.length]);
682            buffer.order(byteOrder);
683            for (double value : values) {
684                buffer.putDouble(value);
685            }
686            return new ExifAttribute(IFD_FORMAT_DOUBLE, values.length, buffer.array());
687        }
688
689        public static ExifAttribute createDouble(double value, ByteOrder byteOrder) {
690            return createDouble(new double[] {value}, byteOrder);
691        }
692
693        @Override
694        public String toString() {
695            return "(" + IFD_FORMAT_NAMES[format] + ", data length:" + bytes.length + ")";
696        }
697
698        private Object getValue(ByteOrder byteOrder) {
699            try {
700                ByteOrderedDataInputStream inputStream =
701                        new ByteOrderedDataInputStream(bytes);
702                inputStream.setByteOrder(byteOrder);
703                switch (format) {
704                    case IFD_FORMAT_BYTE:
705                    case IFD_FORMAT_SBYTE: {
706                        // Exception for GPSAltitudeRef tag
707                        if (bytes.length == 1 && bytes[0] >= 0 && bytes[0] <= 1) {
708                            return new String(new char[] { (char) (bytes[0] + '0') });
709                        }
710                        return new String(bytes, ASCII);
711                    }
712                    case IFD_FORMAT_UNDEFINED:
713                    case IFD_FORMAT_STRING: {
714                        int index = 0;
715                        if (numberOfComponents >= EXIF_ASCII_PREFIX.length) {
716                            boolean same = true;
717                            for (int i = 0; i < EXIF_ASCII_PREFIX.length; ++i) {
718                                if (bytes[i] != EXIF_ASCII_PREFIX[i]) {
719                                    same = false;
720                                    break;
721                                }
722                            }
723                            if (same) {
724                                index = EXIF_ASCII_PREFIX.length;
725                            }
726                        }
727
728                        StringBuilder stringBuilder = new StringBuilder();
729                        while (index < numberOfComponents) {
730                            int ch = bytes[index];
731                            if (ch == 0) {
732                                break;
733                            }
734                            if (ch >= 32) {
735                                stringBuilder.append((char) ch);
736                            } else {
737                                stringBuilder.append('?');
738                            }
739                            ++index;
740                        }
741                        return stringBuilder.toString();
742                    }
743                    case IFD_FORMAT_USHORT: {
744                        final int[] values = new int[numberOfComponents];
745                        for (int i = 0; i < numberOfComponents; ++i) {
746                            values[i] = inputStream.readUnsignedShort();
747                        }
748                        return values;
749                    }
750                    case IFD_FORMAT_ULONG: {
751                        final long[] values = new long[numberOfComponents];
752                        for (int i = 0; i < numberOfComponents; ++i) {
753                            values[i] = inputStream.readUnsignedInt();
754                        }
755                        return values;
756                    }
757                    case IFD_FORMAT_URATIONAL: {
758                        final Rational[] values = new Rational[numberOfComponents];
759                        for (int i = 0; i < numberOfComponents; ++i) {
760                            final long numerator = inputStream.readUnsignedInt();
761                            final long denominator = inputStream.readUnsignedInt();
762                            values[i] = new Rational(numerator, denominator);
763                        }
764                        return values;
765                    }
766                    case IFD_FORMAT_SSHORT: {
767                        final int[] values = new int[numberOfComponents];
768                        for (int i = 0; i < numberOfComponents; ++i) {
769                            values[i] = inputStream.readShort();
770                        }
771                        return values;
772                    }
773                    case IFD_FORMAT_SLONG: {
774                        final int[] values = new int[numberOfComponents];
775                        for (int i = 0; i < numberOfComponents; ++i) {
776                            values[i] = inputStream.readInt();
777                        }
778                        return values;
779                    }
780                    case IFD_FORMAT_SRATIONAL: {
781                        final Rational[] values = new Rational[numberOfComponents];
782                        for (int i = 0; i < numberOfComponents; ++i) {
783                            final long numerator = inputStream.readInt();
784                            final long denominator = inputStream.readInt();
785                            values[i] = new Rational(numerator, denominator);
786                        }
787                        return values;
788                    }
789                    case IFD_FORMAT_SINGLE: {
790                        final double[] values = new double[numberOfComponents];
791                        for (int i = 0; i < numberOfComponents; ++i) {
792                            values[i] = inputStream.readFloat();
793                        }
794                        return values;
795                    }
796                    case IFD_FORMAT_DOUBLE: {
797                        final double[] values = new double[numberOfComponents];
798                        for (int i = 0; i < numberOfComponents; ++i) {
799                            values[i] = inputStream.readDouble();
800                        }
801                        return values;
802                    }
803                    default:
804                        return null;
805                }
806            } catch (IOException e) {
807                Log.w(TAG, "IOException occurred during reading a value", e);
808                return null;
809            }
810        }
811
812        public double getDoubleValue(ByteOrder byteOrder) {
813            Object value = getValue(byteOrder);
814            if (value == null) {
815                throw new NumberFormatException("NULL can't be converted to a double value");
816            }
817            if (value instanceof String) {
818                return Double.parseDouble((String) value);
819            }
820            if (value instanceof long[]) {
821                long[] array = (long[]) value;
822                if (array.length == 1) {
823                    return array[0];
824                }
825                throw new NumberFormatException("There are more than one component");
826            }
827            if (value instanceof int[]) {
828                int[] array = (int[]) value;
829                if (array.length == 1) {
830                    return array[0];
831                }
832                throw new NumberFormatException("There are more than one component");
833            }
834            if (value instanceof double[]) {
835                double[] array = (double[]) value;
836                if (array.length == 1) {
837                    return array[0];
838                }
839                throw new NumberFormatException("There are more than one component");
840            }
841            if (value instanceof Rational[]) {
842                Rational[] array = (Rational[]) value;
843                if (array.length == 1) {
844                    return array[0].calculate();
845                }
846                throw new NumberFormatException("There are more than one component");
847            }
848            throw new NumberFormatException("Couldn't find a double value");
849        }
850
851        public int getIntValue(ByteOrder byteOrder) {
852            Object value = getValue(byteOrder);
853            if (value == null) {
854                throw new NumberFormatException("NULL can't be converted to a integer value");
855            }
856            if (value instanceof String) {
857                return Integer.parseInt((String) value);
858            }
859            if (value instanceof long[]) {
860                long[] array = (long[]) value;
861                if (array.length == 1) {
862                    return (int) array[0];
863                }
864                throw new NumberFormatException("There are more than one component");
865            }
866            if (value instanceof int[]) {
867                int[] array = (int[]) value;
868                if (array.length == 1) {
869                    return array[0];
870                }
871                throw new NumberFormatException("There are more than one component");
872            }
873            throw new NumberFormatException("Couldn't find a integer value");
874        }
875
876        public String getStringValue(ByteOrder byteOrder) {
877            Object value = getValue(byteOrder);
878            if (value == null) {
879                return null;
880            }
881            if (value instanceof String) {
882                return (String) value;
883            }
884
885            final StringBuilder stringBuilder = new StringBuilder();
886            if (value instanceof long[]) {
887                long[] array = (long[]) value;
888                for (int i = 0; i < array.length; ++i) {
889                    stringBuilder.append(array[i]);
890                    if (i + 1 != array.length) {
891                        stringBuilder.append(",");
892                    }
893                }
894                return stringBuilder.toString();
895            }
896            if (value instanceof int[]) {
897                int[] array = (int[]) value;
898                for (int i = 0; i < array.length; ++i) {
899                    stringBuilder.append(array[i]);
900                    if (i + 1 != array.length) {
901                        stringBuilder.append(",");
902                    }
903                }
904                return stringBuilder.toString();
905            }
906            if (value instanceof double[]) {
907                double[] array = (double[]) value;
908                for (int i = 0; i < array.length; ++i) {
909                    stringBuilder.append(array[i]);
910                    if (i + 1 != array.length) {
911                        stringBuilder.append(",");
912                    }
913                }
914                return stringBuilder.toString();
915            }
916            if (value instanceof Rational[]) {
917                Rational[] array = (Rational[]) value;
918                for (int i = 0; i < array.length; ++i) {
919                    stringBuilder.append(array[i].numerator);
920                    stringBuilder.append('/');
921                    stringBuilder.append(array[i].denominator);
922                    if (i + 1 != array.length) {
923                        stringBuilder.append(",");
924                    }
925                }
926                return stringBuilder.toString();
927            }
928            return null;
929        }
930
931        public int size() {
932            return IFD_FORMAT_BYTES_PER_FORMAT[format] * numberOfComponents;
933        }
934    }
935
936    // A class for indicating EXIF tag.
937    private static class ExifTag {
938        public final int number;
939        public final String name;
940        public final int primaryFormat;
941        public final int secondaryFormat;
942
943        private ExifTag(String name, int number, int format) {
944            this.name = name;
945            this.number = number;
946            this.primaryFormat = format;
947            this.secondaryFormat = -1;
948        }
949
950        private ExifTag(String name, int number, int primaryFormat, int secondaryFormat) {
951            this.name = name;
952            this.number = number;
953            this.primaryFormat = primaryFormat;
954            this.secondaryFormat = secondaryFormat;
955        }
956    }
957
958    // Primary image IFD TIFF tags (See JEITA CP-3451C Section 4.6.8 Tag Support Levels)
959    private static final ExifTag[] IFD_TIFF_TAGS = new ExifTag[] {
960            // For below two, see TIFF 6.0 Spec Section 3: Bilevel Images.
961            new ExifTag(TAG_NEW_SUBFILE_TYPE, 254, IFD_FORMAT_ULONG),
962            new ExifTag(TAG_SUBFILE_TYPE, 255, IFD_FORMAT_ULONG),
963            new ExifTag(TAG_IMAGE_WIDTH, 256, IFD_FORMAT_USHORT, IFD_FORMAT_ULONG),
964            new ExifTag(TAG_IMAGE_LENGTH, 257, IFD_FORMAT_USHORT, IFD_FORMAT_ULONG),
965            new ExifTag(TAG_BITS_PER_SAMPLE, 258, IFD_FORMAT_USHORT),
966            new ExifTag(TAG_COMPRESSION, 259, IFD_FORMAT_USHORT),
967            new ExifTag(TAG_PHOTOMETRIC_INTERPRETATION, 262, IFD_FORMAT_USHORT),
968            new ExifTag(TAG_IMAGE_DESCRIPTION, 270, IFD_FORMAT_STRING),
969            new ExifTag(TAG_MAKE, 271, IFD_FORMAT_STRING),
970            new ExifTag(TAG_MODEL, 272, IFD_FORMAT_STRING),
971            new ExifTag(TAG_STRIP_OFFSETS, 273, IFD_FORMAT_USHORT, IFD_FORMAT_ULONG),
972            new ExifTag(TAG_ORIENTATION, 274, IFD_FORMAT_USHORT),
973            new ExifTag(TAG_SAMPLES_PER_PIXEL, 277, IFD_FORMAT_USHORT),
974            new ExifTag(TAG_ROWS_PER_STRIP, 278, IFD_FORMAT_USHORT, IFD_FORMAT_ULONG),
975            new ExifTag(TAG_STRIP_BYTE_COUNTS, 279, IFD_FORMAT_USHORT, IFD_FORMAT_ULONG),
976            new ExifTag(TAG_X_RESOLUTION, 282, IFD_FORMAT_URATIONAL),
977            new ExifTag(TAG_Y_RESOLUTION, 283, IFD_FORMAT_URATIONAL),
978            new ExifTag(TAG_PLANAR_CONFIGURATION, 284, IFD_FORMAT_USHORT),
979            new ExifTag(TAG_RESOLUTION_UNIT, 296, IFD_FORMAT_USHORT),
980            new ExifTag(TAG_TRANSFER_FUNCTION, 301, IFD_FORMAT_USHORT),
981            new ExifTag(TAG_SOFTWARE, 305, IFD_FORMAT_STRING),
982            new ExifTag(TAG_DATETIME, 306, IFD_FORMAT_STRING),
983            new ExifTag(TAG_ARTIST, 315, IFD_FORMAT_STRING),
984            new ExifTag(TAG_WHITE_POINT, 318, IFD_FORMAT_URATIONAL),
985            new ExifTag(TAG_PRIMARY_CHROMATICITIES, 319, IFD_FORMAT_URATIONAL),
986            // See Adobe PageMaker® 6.0 TIFF Technical Notes, Note 1.
987            new ExifTag(TAG_SUB_IFD_POINTER, 330, IFD_FORMAT_ULONG),
988            new ExifTag(TAG_JPEG_INTERCHANGE_FORMAT, 513, IFD_FORMAT_ULONG),
989            new ExifTag(TAG_JPEG_INTERCHANGE_FORMAT_LENGTH, 514, IFD_FORMAT_ULONG),
990            new ExifTag(TAG_Y_CB_CR_COEFFICIENTS, 529, IFD_FORMAT_URATIONAL),
991            new ExifTag(TAG_Y_CB_CR_SUB_SAMPLING, 530, IFD_FORMAT_USHORT),
992            new ExifTag(TAG_Y_CB_CR_POSITIONING, 531, IFD_FORMAT_USHORT),
993            new ExifTag(TAG_REFERENCE_BLACK_WHITE, 532, IFD_FORMAT_URATIONAL),
994            new ExifTag(TAG_COPYRIGHT, 33432, IFD_FORMAT_STRING),
995            new ExifTag(TAG_EXIF_IFD_POINTER, 34665, IFD_FORMAT_ULONG),
996            new ExifTag(TAG_GPS_INFO_IFD_POINTER, 34853, IFD_FORMAT_ULONG),
997            // RW2 file tags
998            // See http://www.sno.phy.queensu.ca/~phil/exiftool/TagNames/PanasonicRaw.html)
999            new ExifTag(TAG_RW2_SENSOR_TOP_BORDER, 4, IFD_FORMAT_ULONG),
1000            new ExifTag(TAG_RW2_SENSOR_LEFT_BORDER, 5, IFD_FORMAT_ULONG),
1001            new ExifTag(TAG_RW2_SENSOR_BOTTOM_BORDER, 6, IFD_FORMAT_ULONG),
1002            new ExifTag(TAG_RW2_SENSOR_RIGHT_BORDER, 7, IFD_FORMAT_ULONG),
1003            new ExifTag(TAG_RW2_ISO, 23, IFD_FORMAT_USHORT),
1004            new ExifTag(TAG_RW2_JPG_FROM_RAW, 46, IFD_FORMAT_UNDEFINED)
1005    };
1006
1007    // Primary image IFD Exif Private tags (See JEITA CP-3451C Section 4.6.8 Tag Support Levels)
1008    private static final ExifTag[] IFD_EXIF_TAGS = new ExifTag[] {
1009            new ExifTag(TAG_EXPOSURE_TIME, 33434, IFD_FORMAT_URATIONAL),
1010            new ExifTag(TAG_F_NUMBER, 33437, IFD_FORMAT_URATIONAL),
1011            new ExifTag(TAG_EXPOSURE_PROGRAM, 34850, IFD_FORMAT_USHORT),
1012            new ExifTag(TAG_SPECTRAL_SENSITIVITY, 34852, IFD_FORMAT_STRING),
1013            new ExifTag(TAG_ISO_SPEED_RATINGS, 34855, IFD_FORMAT_USHORT),
1014            new ExifTag(TAG_OECF, 34856, IFD_FORMAT_UNDEFINED),
1015            new ExifTag(TAG_EXIF_VERSION, 36864, IFD_FORMAT_STRING),
1016            new ExifTag(TAG_DATETIME_ORIGINAL, 36867, IFD_FORMAT_STRING),
1017            new ExifTag(TAG_DATETIME_DIGITIZED, 36868, IFD_FORMAT_STRING),
1018            new ExifTag(TAG_COMPONENTS_CONFIGURATION, 37121, IFD_FORMAT_UNDEFINED),
1019            new ExifTag(TAG_COMPRESSED_BITS_PER_PIXEL, 37122, IFD_FORMAT_URATIONAL),
1020            new ExifTag(TAG_SHUTTER_SPEED_VALUE, 37377, IFD_FORMAT_SRATIONAL),
1021            new ExifTag(TAG_APERTURE_VALUE, 37378, IFD_FORMAT_URATIONAL),
1022            new ExifTag(TAG_BRIGHTNESS_VALUE, 37379, IFD_FORMAT_SRATIONAL),
1023            new ExifTag(TAG_EXPOSURE_BIAS_VALUE, 37380, IFD_FORMAT_SRATIONAL),
1024            new ExifTag(TAG_MAX_APERTURE_VALUE, 37381, IFD_FORMAT_URATIONAL),
1025            new ExifTag(TAG_SUBJECT_DISTANCE, 37382, IFD_FORMAT_URATIONAL),
1026            new ExifTag(TAG_METERING_MODE, 37383, IFD_FORMAT_USHORT),
1027            new ExifTag(TAG_LIGHT_SOURCE, 37384, IFD_FORMAT_USHORT),
1028            new ExifTag(TAG_FLASH, 37385, IFD_FORMAT_USHORT),
1029            new ExifTag(TAG_FOCAL_LENGTH, 37386, IFD_FORMAT_URATIONAL),
1030            new ExifTag(TAG_SUBJECT_AREA, 37396, IFD_FORMAT_USHORT),
1031            new ExifTag(TAG_MAKER_NOTE, 37500, IFD_FORMAT_UNDEFINED),
1032            new ExifTag(TAG_USER_COMMENT, 37510, IFD_FORMAT_UNDEFINED),
1033            new ExifTag(TAG_SUBSEC_TIME, 37520, IFD_FORMAT_STRING),
1034            new ExifTag(TAG_SUBSEC_TIME_ORIG, 37521, IFD_FORMAT_STRING),
1035            new ExifTag(TAG_SUBSEC_TIME_DIG, 37522, IFD_FORMAT_STRING),
1036            new ExifTag(TAG_FLASHPIX_VERSION, 40960, IFD_FORMAT_UNDEFINED),
1037            new ExifTag(TAG_COLOR_SPACE, 40961, IFD_FORMAT_USHORT),
1038            new ExifTag(TAG_PIXEL_X_DIMENSION, 40962, IFD_FORMAT_USHORT, IFD_FORMAT_ULONG),
1039            new ExifTag(TAG_PIXEL_Y_DIMENSION, 40963, IFD_FORMAT_USHORT, IFD_FORMAT_ULONG),
1040            new ExifTag(TAG_RELATED_SOUND_FILE, 40964, IFD_FORMAT_STRING),
1041            new ExifTag(TAG_INTEROPERABILITY_IFD_POINTER, 40965, IFD_FORMAT_ULONG),
1042            new ExifTag(TAG_FLASH_ENERGY, 41483, IFD_FORMAT_URATIONAL),
1043            new ExifTag(TAG_SPATIAL_FREQUENCY_RESPONSE, 41484, IFD_FORMAT_UNDEFINED),
1044            new ExifTag(TAG_FOCAL_PLANE_X_RESOLUTION, 41486, IFD_FORMAT_URATIONAL),
1045            new ExifTag(TAG_FOCAL_PLANE_Y_RESOLUTION, 41487, IFD_FORMAT_URATIONAL),
1046            new ExifTag(TAG_FOCAL_PLANE_RESOLUTION_UNIT, 41488, IFD_FORMAT_USHORT),
1047            new ExifTag(TAG_SUBJECT_LOCATION, 41492, IFD_FORMAT_USHORT),
1048            new ExifTag(TAG_EXPOSURE_INDEX, 41493, IFD_FORMAT_URATIONAL),
1049            new ExifTag(TAG_SENSING_METHOD, 41495, IFD_FORMAT_USHORT),
1050            new ExifTag(TAG_FILE_SOURCE, 41728, IFD_FORMAT_UNDEFINED),
1051            new ExifTag(TAG_SCENE_TYPE, 41729, IFD_FORMAT_UNDEFINED),
1052            new ExifTag(TAG_CFA_PATTERN, 41730, IFD_FORMAT_UNDEFINED),
1053            new ExifTag(TAG_CUSTOM_RENDERED, 41985, IFD_FORMAT_USHORT),
1054            new ExifTag(TAG_EXPOSURE_MODE, 41986, IFD_FORMAT_USHORT),
1055            new ExifTag(TAG_WHITE_BALANCE, 41987, IFD_FORMAT_USHORT),
1056            new ExifTag(TAG_DIGITAL_ZOOM_RATIO, 41988, IFD_FORMAT_URATIONAL),
1057            new ExifTag(TAG_FOCAL_LENGTH_IN_35MM_FILM, 41989, IFD_FORMAT_USHORT),
1058            new ExifTag(TAG_SCENE_CAPTURE_TYPE, 41990, IFD_FORMAT_USHORT),
1059            new ExifTag(TAG_GAIN_CONTROL, 41991, IFD_FORMAT_USHORT),
1060            new ExifTag(TAG_CONTRAST, 41992, IFD_FORMAT_USHORT),
1061            new ExifTag(TAG_SATURATION, 41993, IFD_FORMAT_USHORT),
1062            new ExifTag(TAG_SHARPNESS, 41994, IFD_FORMAT_USHORT),
1063            new ExifTag(TAG_DEVICE_SETTING_DESCRIPTION, 41995, IFD_FORMAT_UNDEFINED),
1064            new ExifTag(TAG_SUBJECT_DISTANCE_RANGE, 41996, IFD_FORMAT_USHORT),
1065            new ExifTag(TAG_IMAGE_UNIQUE_ID, 42016, IFD_FORMAT_STRING),
1066            new ExifTag(TAG_DNG_VERSION, 50706, IFD_FORMAT_BYTE),
1067            new ExifTag(TAG_DEFAULT_CROP_SIZE, 50720, IFD_FORMAT_USHORT, IFD_FORMAT_ULONG)
1068    };
1069
1070    // Primary image IFD GPS Info tags (See JEITA CP-3451C Section 4.6.8 Tag Support Levels)
1071    private static final ExifTag[] IFD_GPS_TAGS = new ExifTag[] {
1072            new ExifTag(TAG_GPS_VERSION_ID, 0, IFD_FORMAT_BYTE),
1073            new ExifTag(TAG_GPS_LATITUDE_REF, 1, IFD_FORMAT_STRING),
1074            new ExifTag(TAG_GPS_LATITUDE, 2, IFD_FORMAT_URATIONAL),
1075            new ExifTag(TAG_GPS_LONGITUDE_REF, 3, IFD_FORMAT_STRING),
1076            new ExifTag(TAG_GPS_LONGITUDE, 4, IFD_FORMAT_URATIONAL),
1077            new ExifTag(TAG_GPS_ALTITUDE_REF, 5, IFD_FORMAT_BYTE),
1078            new ExifTag(TAG_GPS_ALTITUDE, 6, IFD_FORMAT_URATIONAL),
1079            new ExifTag(TAG_GPS_TIMESTAMP, 7, IFD_FORMAT_URATIONAL),
1080            new ExifTag(TAG_GPS_SATELLITES, 8, IFD_FORMAT_STRING),
1081            new ExifTag(TAG_GPS_STATUS, 9, IFD_FORMAT_STRING),
1082            new ExifTag(TAG_GPS_MEASURE_MODE, 10, IFD_FORMAT_STRING),
1083            new ExifTag(TAG_GPS_DOP, 11, IFD_FORMAT_URATIONAL),
1084            new ExifTag(TAG_GPS_SPEED_REF, 12, IFD_FORMAT_STRING),
1085            new ExifTag(TAG_GPS_SPEED, 13, IFD_FORMAT_URATIONAL),
1086            new ExifTag(TAG_GPS_TRACK_REF, 14, IFD_FORMAT_STRING),
1087            new ExifTag(TAG_GPS_TRACK, 15, IFD_FORMAT_URATIONAL),
1088            new ExifTag(TAG_GPS_IMG_DIRECTION_REF, 16, IFD_FORMAT_STRING),
1089            new ExifTag(TAG_GPS_IMG_DIRECTION, 17, IFD_FORMAT_URATIONAL),
1090            new ExifTag(TAG_GPS_MAP_DATUM, 18, IFD_FORMAT_STRING),
1091            new ExifTag(TAG_GPS_DEST_LATITUDE_REF, 19, IFD_FORMAT_STRING),
1092            new ExifTag(TAG_GPS_DEST_LATITUDE, 20, IFD_FORMAT_URATIONAL),
1093            new ExifTag(TAG_GPS_DEST_LONGITUDE_REF, 21, IFD_FORMAT_STRING),
1094            new ExifTag(TAG_GPS_DEST_LONGITUDE, 22, IFD_FORMAT_URATIONAL),
1095            new ExifTag(TAG_GPS_DEST_BEARING_REF, 23, IFD_FORMAT_STRING),
1096            new ExifTag(TAG_GPS_DEST_BEARING, 24, IFD_FORMAT_URATIONAL),
1097            new ExifTag(TAG_GPS_DEST_DISTANCE_REF, 25, IFD_FORMAT_STRING),
1098            new ExifTag(TAG_GPS_DEST_DISTANCE, 26, IFD_FORMAT_URATIONAL),
1099            new ExifTag(TAG_GPS_PROCESSING_METHOD, 27, IFD_FORMAT_UNDEFINED),
1100            new ExifTag(TAG_GPS_AREA_INFORMATION, 28, IFD_FORMAT_UNDEFINED),
1101            new ExifTag(TAG_GPS_DATESTAMP, 29, IFD_FORMAT_STRING),
1102            new ExifTag(TAG_GPS_DIFFERENTIAL, 30, IFD_FORMAT_USHORT)
1103    };
1104    // Primary image IFD Interoperability tag (See JEITA CP-3451C Section 4.6.8 Tag Support Levels)
1105    private static final ExifTag[] IFD_INTEROPERABILITY_TAGS = new ExifTag[] {
1106            new ExifTag(TAG_INTEROPERABILITY_INDEX, 1, IFD_FORMAT_STRING)
1107    };
1108    // IFD Thumbnail tags (See JEITA CP-3451C Section 4.6.8 Tag Support Levels)
1109    private static final ExifTag[] IFD_THUMBNAIL_TAGS = new ExifTag[] {
1110            // For below two, see TIFF 6.0 Spec Section 3: Bilevel Images.
1111            new ExifTag(TAG_NEW_SUBFILE_TYPE, 254, IFD_FORMAT_ULONG),
1112            new ExifTag(TAG_SUBFILE_TYPE, 255, IFD_FORMAT_ULONG),
1113            new ExifTag(TAG_THUMBNAIL_IMAGE_WIDTH, 256, IFD_FORMAT_USHORT, IFD_FORMAT_ULONG),
1114            new ExifTag(TAG_THUMBNAIL_IMAGE_LENGTH, 257, IFD_FORMAT_USHORT, IFD_FORMAT_ULONG),
1115            new ExifTag(TAG_BITS_PER_SAMPLE, 258, IFD_FORMAT_USHORT),
1116            new ExifTag(TAG_COMPRESSION, 259, IFD_FORMAT_USHORT),
1117            new ExifTag(TAG_PHOTOMETRIC_INTERPRETATION, 262, IFD_FORMAT_USHORT),
1118            new ExifTag(TAG_IMAGE_DESCRIPTION, 270, IFD_FORMAT_STRING),
1119            new ExifTag(TAG_MAKE, 271, IFD_FORMAT_STRING),
1120            new ExifTag(TAG_MODEL, 272, IFD_FORMAT_STRING),
1121            new ExifTag(TAG_STRIP_OFFSETS, 273, IFD_FORMAT_USHORT, IFD_FORMAT_ULONG),
1122            new ExifTag(TAG_ORIENTATION, 274, IFD_FORMAT_USHORT),
1123            new ExifTag(TAG_SAMPLES_PER_PIXEL, 277, IFD_FORMAT_USHORT),
1124            new ExifTag(TAG_ROWS_PER_STRIP, 278, IFD_FORMAT_USHORT, IFD_FORMAT_ULONG),
1125            new ExifTag(TAG_STRIP_BYTE_COUNTS, 279, IFD_FORMAT_USHORT, IFD_FORMAT_ULONG),
1126            new ExifTag(TAG_X_RESOLUTION, 282, IFD_FORMAT_URATIONAL),
1127            new ExifTag(TAG_Y_RESOLUTION, 283, IFD_FORMAT_URATIONAL),
1128            new ExifTag(TAG_PLANAR_CONFIGURATION, 284, IFD_FORMAT_USHORT),
1129            new ExifTag(TAG_RESOLUTION_UNIT, 296, IFD_FORMAT_USHORT),
1130            new ExifTag(TAG_TRANSFER_FUNCTION, 301, IFD_FORMAT_USHORT),
1131            new ExifTag(TAG_SOFTWARE, 305, IFD_FORMAT_STRING),
1132            new ExifTag(TAG_DATETIME, 306, IFD_FORMAT_STRING),
1133            new ExifTag(TAG_ARTIST, 315, IFD_FORMAT_STRING),
1134            new ExifTag(TAG_WHITE_POINT, 318, IFD_FORMAT_URATIONAL),
1135            new ExifTag(TAG_PRIMARY_CHROMATICITIES, 319, IFD_FORMAT_URATIONAL),
1136            // See Adobe PageMaker® 6.0 TIFF Technical Notes, Note 1.
1137            new ExifTag(TAG_SUB_IFD_POINTER, 330, IFD_FORMAT_ULONG),
1138            new ExifTag(TAG_JPEG_INTERCHANGE_FORMAT, 513, IFD_FORMAT_ULONG),
1139            new ExifTag(TAG_JPEG_INTERCHANGE_FORMAT_LENGTH, 514, IFD_FORMAT_ULONG),
1140            new ExifTag(TAG_Y_CB_CR_COEFFICIENTS, 529, IFD_FORMAT_URATIONAL),
1141            new ExifTag(TAG_Y_CB_CR_SUB_SAMPLING, 530, IFD_FORMAT_USHORT),
1142            new ExifTag(TAG_Y_CB_CR_POSITIONING, 531, IFD_FORMAT_USHORT),
1143            new ExifTag(TAG_REFERENCE_BLACK_WHITE, 532, IFD_FORMAT_URATIONAL),
1144            new ExifTag(TAG_COPYRIGHT, 33432, IFD_FORMAT_STRING),
1145            new ExifTag(TAG_EXIF_IFD_POINTER, 34665, IFD_FORMAT_ULONG),
1146            new ExifTag(TAG_GPS_INFO_IFD_POINTER, 34853, IFD_FORMAT_ULONG),
1147            new ExifTag(TAG_DNG_VERSION, 50706, IFD_FORMAT_BYTE),
1148            new ExifTag(TAG_DEFAULT_CROP_SIZE, 50720, IFD_FORMAT_USHORT, IFD_FORMAT_ULONG)
1149    };
1150
1151    // RAF file tag (See piex.cc line 372)
1152    private static final ExifTag TAG_RAF_IMAGE_SIZE =
1153            new ExifTag(TAG_STRIP_OFFSETS, 273, IFD_FORMAT_USHORT);
1154
1155    // ORF file tags (See http://www.exiv2.org/tags-olympus.html)
1156    private static final ExifTag[] ORF_MAKER_NOTE_TAGS = new ExifTag[] {
1157            new ExifTag(TAG_ORF_THUMBNAIL_IMAGE, 256, IFD_FORMAT_UNDEFINED),
1158            new ExifTag(TAG_ORF_CAMERA_SETTINGS_IFD_POINTER, 8224, IFD_FORMAT_ULONG),
1159            new ExifTag(TAG_ORF_IMAGE_PROCESSING_IFD_POINTER, 8256, IFD_FORMAT_ULONG)
1160    };
1161    private static final ExifTag[] ORF_CAMERA_SETTINGS_TAGS = new ExifTag[] {
1162            new ExifTag(TAG_ORF_PREVIEW_IMAGE_START, 257, IFD_FORMAT_ULONG),
1163            new ExifTag(TAG_ORF_PREVIEW_IMAGE_LENGTH, 258, IFD_FORMAT_ULONG)
1164    };
1165    private static final ExifTag[] ORF_IMAGE_PROCESSING_TAGS = new ExifTag[] {
1166            new ExifTag(TAG_ORF_ASPECT_FRAME, 4371, IFD_FORMAT_USHORT)
1167    };
1168    // PEF file tag (See http://www.sno.phy.queensu.ca/~phil/exiftool/TagNames/Pentax.html)
1169    private static final ExifTag[] PEF_TAGS = new ExifTag[] {
1170            new ExifTag(TAG_COLOR_SPACE, 55, IFD_FORMAT_USHORT)
1171    };
1172
1173    // See JEITA CP-3451C Section 4.6.3: Exif-specific IFD.
1174    // The following values are used for indicating pointers to the other Image File Directories.
1175
1176    // Indices of Exif Ifd tag groups
1177    /** @hide */
1178    @Retention(RetentionPolicy.SOURCE)
1179    @IntDef({IFD_TYPE_PRIMARY, IFD_TYPE_EXIF, IFD_TYPE_GPS, IFD_TYPE_INTEROPERABILITY,
1180            IFD_TYPE_THUMBNAIL, IFD_TYPE_PREVIEW, IFD_TYPE_ORF_MAKER_NOTE,
1181            IFD_TYPE_ORF_CAMERA_SETTINGS, IFD_TYPE_ORF_IMAGE_PROCESSING, IFD_TYPE_PEF})
1182    public @interface IfdType {}
1183
1184    private static final int IFD_TYPE_PRIMARY = 0;
1185    private static final int IFD_TYPE_EXIF = 1;
1186    private static final int IFD_TYPE_GPS = 2;
1187    private static final int IFD_TYPE_INTEROPERABILITY = 3;
1188    private static final int IFD_TYPE_THUMBNAIL = 4;
1189    private static final int IFD_TYPE_PREVIEW = 5;
1190    private static final int IFD_TYPE_ORF_MAKER_NOTE = 6;
1191    private static final int IFD_TYPE_ORF_CAMERA_SETTINGS = 7;
1192    private static final int IFD_TYPE_ORF_IMAGE_PROCESSING = 8;
1193    private static final int IFD_TYPE_PEF = 9;
1194
1195    // List of Exif tag groups
1196    private static final ExifTag[][] EXIF_TAGS = new ExifTag[][] {
1197            IFD_TIFF_TAGS, IFD_EXIF_TAGS, IFD_GPS_TAGS, IFD_INTEROPERABILITY_TAGS,
1198            IFD_THUMBNAIL_TAGS, IFD_TIFF_TAGS, ORF_MAKER_NOTE_TAGS, ORF_CAMERA_SETTINGS_TAGS,
1199            ORF_IMAGE_PROCESSING_TAGS, PEF_TAGS
1200    };
1201    // List of tags for pointing to the other image file directory offset.
1202    private static final ExifTag[] EXIF_POINTER_TAGS = new ExifTag[] {
1203            new ExifTag(TAG_SUB_IFD_POINTER, 330, IFD_FORMAT_ULONG),
1204            new ExifTag(TAG_EXIF_IFD_POINTER, 34665, IFD_FORMAT_ULONG),
1205            new ExifTag(TAG_GPS_INFO_IFD_POINTER, 34853, IFD_FORMAT_ULONG),
1206            new ExifTag(TAG_INTEROPERABILITY_IFD_POINTER, 40965, IFD_FORMAT_ULONG),
1207            new ExifTag(TAG_ORF_CAMERA_SETTINGS_IFD_POINTER, 8224, IFD_FORMAT_BYTE),
1208            new ExifTag(TAG_ORF_IMAGE_PROCESSING_IFD_POINTER, 8256, IFD_FORMAT_BYTE)
1209    };
1210
1211    // Tags for indicating the thumbnail offset and length
1212    private static final ExifTag JPEG_INTERCHANGE_FORMAT_TAG =
1213            new ExifTag(TAG_JPEG_INTERCHANGE_FORMAT, 513, IFD_FORMAT_ULONG);
1214    private static final ExifTag JPEG_INTERCHANGE_FORMAT_LENGTH_TAG =
1215            new ExifTag(TAG_JPEG_INTERCHANGE_FORMAT_LENGTH, 514, IFD_FORMAT_ULONG);
1216
1217    // Mappings from tag number to tag name and each item represents one IFD tag group.
1218    private static final HashMap[] sExifTagMapsForReading = new HashMap[EXIF_TAGS.length];
1219    // Mappings from tag name to tag number and each item represents one IFD tag group.
1220    private static final HashMap[] sExifTagMapsForWriting = new HashMap[EXIF_TAGS.length];
1221    private static final HashSet<String> sTagSetForCompatibility = new HashSet<>(Arrays.asList(
1222            TAG_F_NUMBER, TAG_DIGITAL_ZOOM_RATIO, TAG_EXPOSURE_TIME, TAG_SUBJECT_DISTANCE,
1223            TAG_GPS_TIMESTAMP));
1224    // Mappings from tag number to IFD type for pointer tags.
1225    private static final HashMap sExifPointerTagMap = new HashMap();
1226
1227    // See JPEG File Interchange Format Version 1.02.
1228    // The following values are defined for handling JPEG streams. In this implementation, we are
1229    // not only getting information from EXIF but also from some JPEG special segments such as
1230    // MARKER_COM for user comment and MARKER_SOFx for image width and height.
1231
1232    private static final Charset ASCII = Charset.forName("US-ASCII");
1233    // Identifier for EXIF APP1 segment in JPEG
1234    private static final byte[] IDENTIFIER_EXIF_APP1 = "Exif\0\0".getBytes(ASCII);
1235    // JPEG segment markers, that each marker consumes two bytes beginning with 0xff and ending with
1236    // the indicator. There is no SOF4, SOF8, SOF16 markers in JPEG and SOFx markers indicates start
1237    // of frame(baseline DCT) and the image size info exists in its beginning part.
1238    private static final byte MARKER = (byte) 0xff;
1239    private static final byte MARKER_SOI = (byte) 0xd8;
1240    private static final byte MARKER_SOF0 = (byte) 0xc0;
1241    private static final byte MARKER_SOF1 = (byte) 0xc1;
1242    private static final byte MARKER_SOF2 = (byte) 0xc2;
1243    private static final byte MARKER_SOF3 = (byte) 0xc3;
1244    private static final byte MARKER_SOF5 = (byte) 0xc5;
1245    private static final byte MARKER_SOF6 = (byte) 0xc6;
1246    private static final byte MARKER_SOF7 = (byte) 0xc7;
1247    private static final byte MARKER_SOF9 = (byte) 0xc9;
1248    private static final byte MARKER_SOF10 = (byte) 0xca;
1249    private static final byte MARKER_SOF11 = (byte) 0xcb;
1250    private static final byte MARKER_SOF13 = (byte) 0xcd;
1251    private static final byte MARKER_SOF14 = (byte) 0xce;
1252    private static final byte MARKER_SOF15 = (byte) 0xcf;
1253    private static final byte MARKER_SOS = (byte) 0xda;
1254    private static final byte MARKER_APP1 = (byte) 0xe1;
1255    private static final byte MARKER_COM = (byte) 0xfe;
1256    private static final byte MARKER_EOI = (byte) 0xd9;
1257
1258    // Supported Image File Types
1259    private static final int IMAGE_TYPE_UNKNOWN = 0;
1260    private static final int IMAGE_TYPE_ARW = 1;
1261    private static final int IMAGE_TYPE_CR2 = 2;
1262    private static final int IMAGE_TYPE_DNG = 3;
1263    private static final int IMAGE_TYPE_JPEG = 4;
1264    private static final int IMAGE_TYPE_NEF = 5;
1265    private static final int IMAGE_TYPE_NRW = 6;
1266    private static final int IMAGE_TYPE_ORF = 7;
1267    private static final int IMAGE_TYPE_PEF = 8;
1268    private static final int IMAGE_TYPE_RAF = 9;
1269    private static final int IMAGE_TYPE_RW2 = 10;
1270    private static final int IMAGE_TYPE_SRW = 11;
1271    private static final int IMAGE_TYPE_HEIF = 12;
1272
1273    static {
1274        sFormatter = new SimpleDateFormat("yyyy:MM:dd HH:mm:ss");
1275        sFormatter.setTimeZone(TimeZone.getTimeZone("UTC"));
1276
1277        // Build up the hash tables to look up Exif tags for reading Exif tags.
1278        for (int ifdType = 0; ifdType < EXIF_TAGS.length; ++ifdType) {
1279            sExifTagMapsForReading[ifdType] = new HashMap();
1280            sExifTagMapsForWriting[ifdType] = new HashMap();
1281            for (ExifTag tag : EXIF_TAGS[ifdType]) {
1282                sExifTagMapsForReading[ifdType].put(tag.number, tag);
1283                sExifTagMapsForWriting[ifdType].put(tag.name, tag);
1284            }
1285        }
1286
1287        // Build up the hash table to look up Exif pointer tags.
1288        sExifPointerTagMap.put(EXIF_POINTER_TAGS[0].number, IFD_TYPE_PREVIEW); // 330
1289        sExifPointerTagMap.put(EXIF_POINTER_TAGS[1].number, IFD_TYPE_EXIF); // 34665
1290        sExifPointerTagMap.put(EXIF_POINTER_TAGS[2].number, IFD_TYPE_GPS); // 34853
1291        sExifPointerTagMap.put(EXIF_POINTER_TAGS[3].number, IFD_TYPE_INTEROPERABILITY); // 40965
1292        sExifPointerTagMap.put(EXIF_POINTER_TAGS[4].number, IFD_TYPE_ORF_CAMERA_SETTINGS); // 8224
1293        sExifPointerTagMap.put(EXIF_POINTER_TAGS[5].number, IFD_TYPE_ORF_IMAGE_PROCESSING); // 8256
1294    }
1295
1296    private final String mFilename;
1297    private final FileDescriptor mSeekableFileDescriptor;
1298    private final AssetManager.AssetInputStream mAssetInputStream;
1299    private final boolean mIsInputStream;
1300    private int mMimeType;
1301    private final HashMap[] mAttributes = new HashMap[EXIF_TAGS.length];
1302    private ByteOrder mExifByteOrder = ByteOrder.BIG_ENDIAN;
1303    private boolean mHasThumbnail;
1304    // The following values used for indicating a thumbnail position.
1305    private int mThumbnailOffset;
1306    private int mThumbnailLength;
1307    private byte[] mThumbnailBytes;
1308    private int mThumbnailCompression;
1309    private int mExifOffset;
1310    private int mOrfMakerNoteOffset;
1311    private int mOrfThumbnailOffset;
1312    private int mOrfThumbnailLength;
1313    private int mRw2JpgFromRawOffset;
1314    private boolean mIsSupportedFile;
1315
1316    // Pattern to check non zero timestamp
1317    private static final Pattern sNonZeroTimePattern = Pattern.compile(".*[1-9].*");
1318    // Pattern to check gps timestamp
1319    private static final Pattern sGpsTimestampPattern =
1320            Pattern.compile("^([0-9][0-9]):([0-9][0-9]):([0-9][0-9])$");
1321
1322    /**
1323     * Reads Exif tags from the specified image file.
1324     */
1325    public ExifInterface(String filename) throws IOException {
1326        if (filename == null) {
1327            throw new IllegalArgumentException("filename cannot be null");
1328        }
1329        FileInputStream in = null;
1330        mAssetInputStream = null;
1331        mFilename = filename;
1332        mIsInputStream = false;
1333        try {
1334            in = new FileInputStream(filename);
1335            if (isSeekableFD(in.getFD())) {
1336                mSeekableFileDescriptor = in.getFD();
1337            } else {
1338                mSeekableFileDescriptor = null;
1339            }
1340            loadAttributes(in);
1341        } finally {
1342            IoUtils.closeQuietly(in);
1343        }
1344    }
1345
1346    /**
1347     * Reads Exif tags from the specified image file descriptor. Attribute mutation is supported
1348     * for writable and seekable file descriptors only. This constructor will not rewind the offset
1349     * of the given file descriptor. Developers should close the file descriptor after use.
1350     */
1351    public ExifInterface(FileDescriptor fileDescriptor) throws IOException {
1352        if (fileDescriptor == null) {
1353            throw new IllegalArgumentException("fileDescriptor cannot be null");
1354        }
1355        mAssetInputStream = null;
1356        mFilename = null;
1357        if (isSeekableFD(fileDescriptor)) {
1358            mSeekableFileDescriptor = fileDescriptor;
1359            // Keep the original file descriptor in order to save attributes when it's seekable.
1360            // Otherwise, just close the given file descriptor after reading it because the save
1361            // feature won't be working.
1362            try {
1363                fileDescriptor = Os.dup(fileDescriptor);
1364            } catch (ErrnoException e) {
1365                throw e.rethrowAsIOException();
1366            }
1367        } else {
1368            mSeekableFileDescriptor = null;
1369        }
1370        mIsInputStream = false;
1371        FileInputStream in = null;
1372        try {
1373            in = new FileInputStream(fileDescriptor);
1374            loadAttributes(in);
1375        } finally {
1376            IoUtils.closeQuietly(in);
1377        }
1378    }
1379
1380    /**
1381     * Reads Exif tags from the specified image input stream. Attribute mutation is not supported
1382     * for input streams. The given input stream will proceed its current position. Developers
1383     * should close the input stream after use.
1384     */
1385    public ExifInterface(InputStream inputStream) throws IOException {
1386        if (inputStream == null) {
1387            throw new IllegalArgumentException("inputStream cannot be null");
1388        }
1389        mFilename = null;
1390        if (inputStream instanceof AssetManager.AssetInputStream) {
1391            mAssetInputStream = (AssetManager.AssetInputStream) inputStream;
1392            mSeekableFileDescriptor = null;
1393        } else if (inputStream instanceof FileInputStream
1394                && isSeekableFD(((FileInputStream) inputStream).getFD())) {
1395            mAssetInputStream = null;
1396            mSeekableFileDescriptor = ((FileInputStream) inputStream).getFD();
1397        } else {
1398            mAssetInputStream = null;
1399            mSeekableFileDescriptor = null;
1400        }
1401        mIsInputStream = true;
1402        loadAttributes(inputStream);
1403    }
1404
1405    /**
1406     * Returns the EXIF attribute of the specified tag or {@code null} if there is no such tag in
1407     * the image file.
1408     *
1409     * @param tag the name of the tag.
1410     */
1411    private ExifAttribute getExifAttribute(String tag) {
1412        // Retrieves all tag groups. The value from primary image tag group has a higher priority
1413        // than the value from the thumbnail tag group if there are more than one candidates.
1414        for (int i = 0; i < EXIF_TAGS.length; ++i) {
1415            Object value = mAttributes[i].get(tag);
1416            if (value != null) {
1417                return (ExifAttribute) value;
1418            }
1419        }
1420        return null;
1421    }
1422
1423    /**
1424     * Returns the value of the specified tag or {@code null} if there
1425     * is no such tag in the image file.
1426     *
1427     * @param tag the name of the tag.
1428     */
1429    public String getAttribute(String tag) {
1430        ExifAttribute attribute = getExifAttribute(tag);
1431        if (attribute != null) {
1432            if (!sTagSetForCompatibility.contains(tag)) {
1433                return attribute.getStringValue(mExifByteOrder);
1434            }
1435            if (tag.equals(TAG_GPS_TIMESTAMP)) {
1436                // Convert the rational values to the custom formats for backwards compatibility.
1437                if (attribute.format != IFD_FORMAT_URATIONAL
1438                        && attribute.format != IFD_FORMAT_SRATIONAL) {
1439                    return null;
1440                }
1441                Rational[] array = (Rational[]) attribute.getValue(mExifByteOrder);
1442                if (array.length != 3) {
1443                    return null;
1444                }
1445                return String.format("%02d:%02d:%02d",
1446                        (int) ((float) array[0].numerator / array[0].denominator),
1447                        (int) ((float) array[1].numerator / array[1].denominator),
1448                        (int) ((float) array[2].numerator / array[2].denominator));
1449            }
1450            try {
1451                return Double.toString(attribute.getDoubleValue(mExifByteOrder));
1452            } catch (NumberFormatException e) {
1453                return null;
1454            }
1455        }
1456        return null;
1457    }
1458
1459    /**
1460     * Returns the integer value of the specified tag. If there is no such tag
1461     * in the image file or the value cannot be parsed as integer, return
1462     * <var>defaultValue</var>.
1463     *
1464     * @param tag the name of the tag.
1465     * @param defaultValue the value to return if the tag is not available.
1466     */
1467    public int getAttributeInt(String tag, int defaultValue) {
1468        ExifAttribute exifAttribute = getExifAttribute(tag);
1469        if (exifAttribute == null) {
1470            return defaultValue;
1471        }
1472
1473        try {
1474            return exifAttribute.getIntValue(mExifByteOrder);
1475        } catch (NumberFormatException e) {
1476            return defaultValue;
1477        }
1478    }
1479
1480    /**
1481     * Returns the double value of the tag that is specified as rational or contains a
1482     * double-formatted value. If there is no such tag in the image file or the value cannot be
1483     * parsed as double, return <var>defaultValue</var>.
1484     *
1485     * @param tag the name of the tag.
1486     * @param defaultValue the value to return if the tag is not available.
1487     */
1488    public double getAttributeDouble(String tag, double defaultValue) {
1489        ExifAttribute exifAttribute = getExifAttribute(tag);
1490        if (exifAttribute == null) {
1491            return defaultValue;
1492        }
1493
1494        try {
1495            return exifAttribute.getDoubleValue(mExifByteOrder);
1496        } catch (NumberFormatException e) {
1497            return defaultValue;
1498        }
1499    }
1500
1501    /**
1502     * Set the value of the specified tag.
1503     *
1504     * @param tag the name of the tag.
1505     * @param value the value of the tag.
1506     */
1507    public void setAttribute(String tag, String value) {
1508        // Convert the given value to rational values for backwards compatibility.
1509        if (value != null && sTagSetForCompatibility.contains(tag)) {
1510            if (tag.equals(TAG_GPS_TIMESTAMP)) {
1511                Matcher m = sGpsTimestampPattern.matcher(value);
1512                if (!m.find()) {
1513                    Log.w(TAG, "Invalid value for " + tag + " : " + value);
1514                    return;
1515                }
1516                value = Integer.parseInt(m.group(1)) + "/1," + Integer.parseInt(m.group(2)) + "/1,"
1517                        + Integer.parseInt(m.group(3)) + "/1";
1518            } else {
1519                try {
1520                    double doubleValue = Double.parseDouble(value);
1521                    value = (long) (doubleValue * 10000L) + "/10000";
1522                } catch (NumberFormatException e) {
1523                    Log.w(TAG, "Invalid value for " + tag + " : " + value);
1524                    return;
1525                }
1526            }
1527        }
1528
1529        for (int i = 0 ; i < EXIF_TAGS.length; ++i) {
1530            if (i == IFD_TYPE_THUMBNAIL && !mHasThumbnail) {
1531                continue;
1532            }
1533            final Object obj = sExifTagMapsForWriting[i].get(tag);
1534            if (obj != null) {
1535                if (value == null) {
1536                    mAttributes[i].remove(tag);
1537                    continue;
1538                }
1539                final ExifTag exifTag = (ExifTag) obj;
1540                Pair<Integer, Integer> guess = guessDataFormat(value);
1541                int dataFormat;
1542                if (exifTag.primaryFormat == guess.first || exifTag.primaryFormat == guess.second) {
1543                    dataFormat = exifTag.primaryFormat;
1544                } else if (exifTag.secondaryFormat != -1 && (exifTag.secondaryFormat == guess.first
1545                        || exifTag.secondaryFormat == guess.second)) {
1546                    dataFormat = exifTag.secondaryFormat;
1547                } else if (exifTag.primaryFormat == IFD_FORMAT_BYTE
1548                        || exifTag.primaryFormat == IFD_FORMAT_UNDEFINED
1549                        || exifTag.primaryFormat == IFD_FORMAT_STRING) {
1550                    dataFormat = exifTag.primaryFormat;
1551                } else {
1552                    Log.w(TAG, "Given tag (" + tag + ") value didn't match with one of expected "
1553                            + "formats: " + IFD_FORMAT_NAMES[exifTag.primaryFormat]
1554                            + (exifTag.secondaryFormat == -1 ? "" : ", "
1555                            + IFD_FORMAT_NAMES[exifTag.secondaryFormat]) + " (guess: "
1556                            + IFD_FORMAT_NAMES[guess.first] + (guess.second == -1 ? "" : ", "
1557                            + IFD_FORMAT_NAMES[guess.second]) + ")");
1558                    continue;
1559                }
1560                switch (dataFormat) {
1561                    case IFD_FORMAT_BYTE: {
1562                        mAttributes[i].put(tag, ExifAttribute.createByte(value));
1563                        break;
1564                    }
1565                    case IFD_FORMAT_UNDEFINED:
1566                    case IFD_FORMAT_STRING: {
1567                        mAttributes[i].put(tag, ExifAttribute.createString(value));
1568                        break;
1569                    }
1570                    case IFD_FORMAT_USHORT: {
1571                        final String[] values = value.split(",");
1572                        final int[] intArray = new int[values.length];
1573                        for (int j = 0; j < values.length; ++j) {
1574                            intArray[j] = Integer.parseInt(values[j]);
1575                        }
1576                        mAttributes[i].put(tag,
1577                                ExifAttribute.createUShort(intArray, mExifByteOrder));
1578                        break;
1579                    }
1580                    case IFD_FORMAT_SLONG: {
1581                        final String[] values = value.split(",");
1582                        final int[] intArray = new int[values.length];
1583                        for (int j = 0; j < values.length; ++j) {
1584                            intArray[j] = Integer.parseInt(values[j]);
1585                        }
1586                        mAttributes[i].put(tag,
1587                                ExifAttribute.createSLong(intArray, mExifByteOrder));
1588                        break;
1589                    }
1590                    case IFD_FORMAT_ULONG: {
1591                        final String[] values = value.split(",");
1592                        final long[] longArray = new long[values.length];
1593                        for (int j = 0; j < values.length; ++j) {
1594                            longArray[j] = Long.parseLong(values[j]);
1595                        }
1596                        mAttributes[i].put(tag,
1597                                ExifAttribute.createULong(longArray, mExifByteOrder));
1598                        break;
1599                    }
1600                    case IFD_FORMAT_URATIONAL: {
1601                        final String[] values = value.split(",");
1602                        final Rational[] rationalArray = new Rational[values.length];
1603                        for (int j = 0; j < values.length; ++j) {
1604                            final String[] numbers = values[j].split("/");
1605                            rationalArray[j] = new Rational((long) Double.parseDouble(numbers[0]),
1606                                    (long) Double.parseDouble(numbers[1]));
1607                        }
1608                        mAttributes[i].put(tag,
1609                                ExifAttribute.createURational(rationalArray, mExifByteOrder));
1610                        break;
1611                    }
1612                    case IFD_FORMAT_SRATIONAL: {
1613                        final String[] values = value.split(",");
1614                        final Rational[] rationalArray = new Rational[values.length];
1615                        for (int j = 0; j < values.length; ++j) {
1616                            final String[] numbers = values[j].split("/");
1617                            rationalArray[j] = new Rational((long) Double.parseDouble(numbers[0]),
1618                                    (long) Double.parseDouble(numbers[1]));
1619                        }
1620                        mAttributes[i].put(tag,
1621                                ExifAttribute.createSRational(rationalArray, mExifByteOrder));
1622                        break;
1623                    }
1624                    case IFD_FORMAT_DOUBLE: {
1625                        final String[] values = value.split(",");
1626                        final double[] doubleArray = new double[values.length];
1627                        for (int j = 0; j < values.length; ++j) {
1628                            doubleArray[j] = Double.parseDouble(values[j]);
1629                        }
1630                        mAttributes[i].put(tag,
1631                                ExifAttribute.createDouble(doubleArray, mExifByteOrder));
1632                        break;
1633                    }
1634                    default:
1635                        Log.w(TAG, "Data format isn't one of expected formats: " + dataFormat);
1636                        continue;
1637                }
1638            }
1639        }
1640    }
1641
1642    /**
1643     * Update the values of the tags in the tag groups if any value for the tag already was stored.
1644     *
1645     * @param tag the name of the tag.
1646     * @param value the value of the tag in a form of {@link ExifAttribute}.
1647     * @return Returns {@code true} if updating is placed.
1648     */
1649    private boolean updateAttribute(String tag, ExifAttribute value) {
1650        boolean updated = false;
1651        for (int i = 0 ; i < EXIF_TAGS.length; ++i) {
1652            if (mAttributes[i].containsKey(tag)) {
1653                mAttributes[i].put(tag, value);
1654                updated = true;
1655            }
1656        }
1657        return updated;
1658    }
1659
1660    /**
1661     * Remove any values of the specified tag.
1662     *
1663     * @param tag the name of the tag.
1664     */
1665    private void removeAttribute(String tag) {
1666        for (int i = 0 ; i < EXIF_TAGS.length; ++i) {
1667            mAttributes[i].remove(tag);
1668        }
1669    }
1670
1671    /**
1672     * This function decides which parser to read the image data according to the given input stream
1673     * type and the content of the input stream. In each case, it reads the first three bytes to
1674     * determine whether the image data format is JPEG or not.
1675     */
1676    private void loadAttributes(@NonNull InputStream in) throws IOException {
1677        try {
1678            // Initialize mAttributes.
1679            for (int i = 0; i < EXIF_TAGS.length; ++i) {
1680                mAttributes[i] = new HashMap();
1681            }
1682
1683            // Check file type
1684            in = new BufferedInputStream(in, SIGNATURE_CHECK_SIZE);
1685            mMimeType = getMimeType((BufferedInputStream) in);
1686
1687            // Create byte-ordered input stream
1688            ByteOrderedDataInputStream inputStream = new ByteOrderedDataInputStream(in);
1689
1690            switch (mMimeType) {
1691                case IMAGE_TYPE_JPEG: {
1692                    getJpegAttributes(inputStream, 0, IFD_TYPE_PRIMARY); // 0 is offset
1693                    break;
1694                }
1695                case IMAGE_TYPE_RAF: {
1696                    getRafAttributes(inputStream);
1697                    break;
1698                }
1699                case IMAGE_TYPE_HEIF: {
1700                    getHeifAttributes(inputStream);
1701                    break;
1702                }
1703                case IMAGE_TYPE_ORF: {
1704                    getOrfAttributes(inputStream);
1705                    break;
1706                }
1707                case IMAGE_TYPE_RW2: {
1708                    getRw2Attributes(inputStream);
1709                    break;
1710                }
1711                case IMAGE_TYPE_ARW:
1712                case IMAGE_TYPE_CR2:
1713                case IMAGE_TYPE_DNG:
1714                case IMAGE_TYPE_NEF:
1715                case IMAGE_TYPE_NRW:
1716                case IMAGE_TYPE_PEF:
1717                case IMAGE_TYPE_SRW:
1718                case IMAGE_TYPE_UNKNOWN: {
1719                    getRawAttributes(inputStream);
1720                    break;
1721                }
1722                default: {
1723                    break;
1724                }
1725            }
1726            // Set thumbnail image offset and length
1727            setThumbnailData(inputStream);
1728            mIsSupportedFile = true;
1729        } catch (IOException e) {
1730            // Ignore exceptions in order to keep the compatibility with the old versions of
1731            // ExifInterface.
1732            mIsSupportedFile = false;
1733            if (DEBUG) {
1734                Log.w(TAG, "Invalid image: ExifInterface got an unsupported image format file"
1735                        + "(ExifInterface supports JPEG and some RAW image formats only) "
1736                        + "or a corrupted JPEG file to ExifInterface.", e);
1737            }
1738        } finally {
1739            addDefaultValuesForCompatibility();
1740
1741            if (DEBUG) {
1742                printAttributes();
1743            }
1744        }
1745    }
1746
1747    private static boolean isSeekableFD(FileDescriptor fd) throws IOException {
1748        try {
1749            Os.lseek(fd, 0, OsConstants.SEEK_CUR);
1750            return true;
1751        } catch (ErrnoException e) {
1752            return false;
1753        }
1754    }
1755
1756    // Prints out attributes for debugging.
1757    private void printAttributes() {
1758        for (int i = 0; i < mAttributes.length; ++i) {
1759            Log.d(TAG, "The size of tag group[" + i + "]: " + mAttributes[i].size());
1760            for (Map.Entry entry : (Set<Map.Entry>) mAttributes[i].entrySet()) {
1761                final ExifAttribute tagValue = (ExifAttribute) entry.getValue();
1762                Log.d(TAG, "tagName: " + entry.getKey() + ", tagType: " + tagValue.toString()
1763                        + ", tagValue: '" + tagValue.getStringValue(mExifByteOrder) + "'");
1764            }
1765        }
1766    }
1767
1768    /**
1769     * Save the tag data into the original image file. This is expensive because it involves
1770     * copying all the data from one file to another and deleting the old file and renaming the
1771     * other. It's best to use {@link #setAttribute(String,String)} to set all attributes to write
1772     * and make a single call rather than multiple calls for each attribute.
1773     * <p>
1774     * This method is only supported for JPEG files.
1775     * </p>
1776     */
1777    public void saveAttributes() throws IOException {
1778        if (!mIsSupportedFile || mMimeType != IMAGE_TYPE_JPEG) {
1779            throw new IOException("ExifInterface only supports saving attributes on JPEG formats.");
1780        }
1781        if (mIsInputStream || (mSeekableFileDescriptor == null && mFilename == null)) {
1782            throw new IOException(
1783                    "ExifInterface does not support saving attributes for the current input.");
1784        }
1785
1786        // Keep the thumbnail in memory
1787        mThumbnailBytes = getThumbnail();
1788
1789        FileInputStream in = null;
1790        FileOutputStream out = null;
1791        File tempFile = null;
1792        try {
1793            // Move the original file to temporary file.
1794            if (mFilename != null) {
1795                tempFile = new File(mFilename + ".tmp");
1796                File originalFile = new File(mFilename);
1797                if (!originalFile.renameTo(tempFile)) {
1798                    throw new IOException("Could'nt rename to " + tempFile.getAbsolutePath());
1799                }
1800            } else if (mSeekableFileDescriptor != null) {
1801                tempFile = File.createTempFile("temp", "jpg");
1802                Os.lseek(mSeekableFileDescriptor, 0, OsConstants.SEEK_SET);
1803                in = new FileInputStream(mSeekableFileDescriptor);
1804                out = new FileOutputStream(tempFile);
1805                Streams.copy(in, out);
1806            }
1807        } catch (ErrnoException e) {
1808            throw e.rethrowAsIOException();
1809        } finally {
1810            IoUtils.closeQuietly(in);
1811            IoUtils.closeQuietly(out);
1812        }
1813
1814        in = null;
1815        out = null;
1816        try {
1817            // Save the new file.
1818            in = new FileInputStream(tempFile);
1819            if (mFilename != null) {
1820                out = new FileOutputStream(mFilename);
1821            } else if (mSeekableFileDescriptor != null) {
1822                Os.lseek(mSeekableFileDescriptor, 0, OsConstants.SEEK_SET);
1823                out = new FileOutputStream(mSeekableFileDescriptor);
1824            }
1825            saveJpegAttributes(in, out);
1826        } catch (ErrnoException e) {
1827            throw e.rethrowAsIOException();
1828        } finally {
1829            IoUtils.closeQuietly(in);
1830            IoUtils.closeQuietly(out);
1831            tempFile.delete();
1832        }
1833
1834        // Discard the thumbnail in memory
1835        mThumbnailBytes = null;
1836    }
1837
1838    /**
1839     * Returns true if the image file has a thumbnail.
1840     */
1841    public boolean hasThumbnail() {
1842        return mHasThumbnail;
1843    }
1844
1845    /**
1846     * Returns the JPEG compressed thumbnail inside the image file, or {@code null} if there is no
1847     * JPEG compressed thumbnail.
1848     * The returned data can be decoded using
1849     * {@link android.graphics.BitmapFactory#decodeByteArray(byte[],int,int)}
1850     */
1851    public byte[] getThumbnail() {
1852        if (mThumbnailCompression == DATA_JPEG || mThumbnailCompression == DATA_JPEG_COMPRESSED) {
1853            return getThumbnailBytes();
1854        }
1855        return null;
1856    }
1857
1858    /**
1859     * Returns the thumbnail bytes inside the image file, regardless of the compression type of the
1860     * thumbnail image.
1861     */
1862    public byte[] getThumbnailBytes() {
1863        if (!mHasThumbnail) {
1864            return null;
1865        }
1866        if (mThumbnailBytes != null) {
1867            return mThumbnailBytes;
1868        }
1869
1870        // Read the thumbnail.
1871        InputStream in = null;
1872        try {
1873            if (mAssetInputStream != null) {
1874                in = mAssetInputStream;
1875                if (in.markSupported()) {
1876                    in.reset();
1877                } else {
1878                    Log.d(TAG, "Cannot read thumbnail from inputstream without mark/reset support");
1879                    return null;
1880                }
1881            } else if (mFilename != null) {
1882                in = new FileInputStream(mFilename);
1883            } else if (mSeekableFileDescriptor != null) {
1884                FileDescriptor fileDescriptor = Os.dup(mSeekableFileDescriptor);
1885                Os.lseek(fileDescriptor, 0, OsConstants.SEEK_SET);
1886                in = new FileInputStream(fileDescriptor);
1887            }
1888            if (in == null) {
1889                // Should not be reached this.
1890                throw new FileNotFoundException();
1891            }
1892            if (in.skip(mThumbnailOffset) != mThumbnailOffset) {
1893                throw new IOException("Corrupted image");
1894            }
1895            byte[] buffer = new byte[mThumbnailLength];
1896            if (in.read(buffer) != mThumbnailLength) {
1897                throw new IOException("Corrupted image");
1898            }
1899            mThumbnailBytes = buffer;
1900            return buffer;
1901        } catch (IOException | ErrnoException e) {
1902            // Couldn't get a thumbnail image.
1903            Log.d(TAG, "Encountered exception while getting thumbnail", e);
1904        } finally {
1905            IoUtils.closeQuietly(in);
1906        }
1907        return null;
1908    }
1909
1910    /**
1911     * Creates and returns a Bitmap object of the thumbnail image based on the byte array and the
1912     * thumbnail compression value, or {@code null} if the compression type is unsupported.
1913     */
1914    public Bitmap getThumbnailBitmap() {
1915        if (!mHasThumbnail) {
1916            return null;
1917        } else if (mThumbnailBytes == null) {
1918            mThumbnailBytes = getThumbnailBytes();
1919        }
1920
1921        if (mThumbnailCompression == DATA_JPEG || mThumbnailCompression == DATA_JPEG_COMPRESSED) {
1922            return BitmapFactory.decodeByteArray(mThumbnailBytes, 0, mThumbnailLength);
1923        } else if (mThumbnailCompression == DATA_UNCOMPRESSED) {
1924            int[] rgbValues = new int[mThumbnailBytes.length / 3];
1925            byte alpha = (byte) 0xff000000;
1926            for (int i = 0; i < rgbValues.length; i++) {
1927                rgbValues[i] = alpha + (mThumbnailBytes[3 * i] << 16)
1928                        + (mThumbnailBytes[3 * i + 1] << 8) + mThumbnailBytes[3 * i + 2];
1929            }
1930
1931            ExifAttribute imageLengthAttribute =
1932                    (ExifAttribute) mAttributes[IFD_TYPE_THUMBNAIL].get(TAG_IMAGE_LENGTH);
1933            ExifAttribute imageWidthAttribute =
1934                    (ExifAttribute) mAttributes[IFD_TYPE_THUMBNAIL].get(TAG_IMAGE_WIDTH);
1935            if (imageLengthAttribute != null && imageWidthAttribute != null) {
1936                int imageLength = imageLengthAttribute.getIntValue(mExifByteOrder);
1937                int imageWidth = imageWidthAttribute.getIntValue(mExifByteOrder);
1938                return Bitmap.createBitmap(
1939                        rgbValues, imageWidth, imageLength, Bitmap.Config.ARGB_8888);
1940            }
1941        }
1942        return null;
1943    }
1944
1945    /**
1946     * Returns true if thumbnail image is JPEG Compressed, or false if either thumbnail image does
1947     * not exist or thumbnail image is uncompressed.
1948     */
1949    public boolean isThumbnailCompressed() {
1950        if (!mHasThumbnail) {
1951            return false;
1952        }
1953        if (mThumbnailCompression == DATA_JPEG || mThumbnailCompression == DATA_JPEG_COMPRESSED) {
1954            return true;
1955        }
1956        return false;
1957    }
1958
1959    /**
1960     * Returns the offset and length of thumbnail inside the image file, or
1961     * {@code null} if there is no thumbnail.
1962     *
1963     * @return two-element array, the offset in the first value, and length in
1964     *         the second, or {@code null} if no thumbnail was found.
1965     */
1966    public long[] getThumbnailRange() {
1967        if (!mHasThumbnail) {
1968            return null;
1969        }
1970
1971        long[] range = new long[2];
1972        range[0] = mThumbnailOffset;
1973        range[1] = mThumbnailLength;
1974
1975        return range;
1976    }
1977
1978    /**
1979     * Stores the latitude and longitude value in a float array. The first element is
1980     * the latitude, and the second element is the longitude. Returns false if the
1981     * Exif tags are not available.
1982     */
1983    public boolean getLatLong(float output[]) {
1984        String latValue = getAttribute(TAG_GPS_LATITUDE);
1985        String latRef = getAttribute(TAG_GPS_LATITUDE_REF);
1986        String lngValue = getAttribute(TAG_GPS_LONGITUDE);
1987        String lngRef = getAttribute(TAG_GPS_LONGITUDE_REF);
1988
1989        if (latValue != null && latRef != null && lngValue != null && lngRef != null) {
1990            try {
1991                output[0] = convertRationalLatLonToFloat(latValue, latRef);
1992                output[1] = convertRationalLatLonToFloat(lngValue, lngRef);
1993                return true;
1994            } catch (IllegalArgumentException e) {
1995                // if values are not parseable
1996            }
1997        }
1998
1999        return false;
2000    }
2001
2002    /**
2003     * Return the altitude in meters. If the exif tag does not exist, return
2004     * <var>defaultValue</var>.
2005     *
2006     * @param defaultValue the value to return if the tag is not available.
2007     */
2008    public double getAltitude(double defaultValue) {
2009        double altitude = getAttributeDouble(TAG_GPS_ALTITUDE, -1);
2010        int ref = getAttributeInt(TAG_GPS_ALTITUDE_REF, -1);
2011
2012        if (altitude >= 0 && ref >= 0) {
2013            return (altitude * ((ref == 1) ? -1 : 1));
2014        } else {
2015            return defaultValue;
2016        }
2017    }
2018
2019    /**
2020     * Returns number of milliseconds since Jan. 1, 1970, midnight local time.
2021     * Returns -1 if the date time information if not available.
2022     * @hide
2023     */
2024    public long getDateTime() {
2025        String dateTimeString = getAttribute(TAG_DATETIME);
2026        if (dateTimeString == null
2027                || !sNonZeroTimePattern.matcher(dateTimeString).matches()) return -1;
2028
2029        ParsePosition pos = new ParsePosition(0);
2030        try {
2031            // The exif field is in local time. Parsing it as if it is UTC will yield time
2032            // since 1/1/1970 local time
2033            Date datetime = sFormatter.parse(dateTimeString, pos);
2034            if (datetime == null) return -1;
2035            long msecs = datetime.getTime();
2036
2037            String subSecs = getAttribute(TAG_SUBSEC_TIME);
2038            if (subSecs != null) {
2039                try {
2040                    long sub = Long.parseLong(subSecs);
2041                    while (sub > 1000) {
2042                        sub /= 10;
2043                    }
2044                    msecs += sub;
2045                } catch (NumberFormatException e) {
2046                    // Ignored
2047                }
2048            }
2049            return msecs;
2050        } catch (IllegalArgumentException e) {
2051            return -1;
2052        }
2053    }
2054
2055    /**
2056     * Returns number of milliseconds since Jan. 1, 1970, midnight UTC.
2057     * Returns -1 if the date time information if not available.
2058     * @hide
2059     */
2060    public long getGpsDateTime() {
2061        String date = getAttribute(TAG_GPS_DATESTAMP);
2062        String time = getAttribute(TAG_GPS_TIMESTAMP);
2063        if (date == null || time == null
2064                || (!sNonZeroTimePattern.matcher(date).matches()
2065                && !sNonZeroTimePattern.matcher(time).matches())) {
2066            return -1;
2067        }
2068
2069        String dateTimeString = date + ' ' + time;
2070
2071        ParsePosition pos = new ParsePosition(0);
2072        try {
2073            Date datetime = sFormatter.parse(dateTimeString, pos);
2074            if (datetime == null) return -1;
2075            return datetime.getTime();
2076        } catch (IllegalArgumentException e) {
2077            return -1;
2078        }
2079    }
2080
2081    /** {@hide} */
2082    public static float convertRationalLatLonToFloat(String rationalString, String ref) {
2083        try {
2084            String [] parts = rationalString.split(",");
2085
2086            String [] pair;
2087            pair = parts[0].split("/");
2088            double degrees = Double.parseDouble(pair[0].trim())
2089                    / Double.parseDouble(pair[1].trim());
2090
2091            pair = parts[1].split("/");
2092            double minutes = Double.parseDouble(pair[0].trim())
2093                    / Double.parseDouble(pair[1].trim());
2094
2095            pair = parts[2].split("/");
2096            double seconds = Double.parseDouble(pair[0].trim())
2097                    / Double.parseDouble(pair[1].trim());
2098
2099            double result = degrees + (minutes / 60.0) + (seconds / 3600.0);
2100            if ((ref.equals("S") || ref.equals("W"))) {
2101                return (float) -result;
2102            }
2103            return (float) result;
2104        } catch (NumberFormatException | ArrayIndexOutOfBoundsException e) {
2105            // Not valid
2106            throw new IllegalArgumentException();
2107        }
2108    }
2109
2110    // Checks the type of image file
2111    private int getMimeType(BufferedInputStream in) throws IOException {
2112        in.mark(SIGNATURE_CHECK_SIZE);
2113        byte[] signatureCheckBytes = new byte[SIGNATURE_CHECK_SIZE];
2114        in.read(signatureCheckBytes);
2115        in.reset();
2116        if (isJpegFormat(signatureCheckBytes)) {
2117            return IMAGE_TYPE_JPEG;
2118        } else if (isRafFormat(signatureCheckBytes)) {
2119            return IMAGE_TYPE_RAF;
2120        } else if (isHeifFormat(signatureCheckBytes)) {
2121            return IMAGE_TYPE_HEIF;
2122        } else if (isOrfFormat(signatureCheckBytes)) {
2123            return IMAGE_TYPE_ORF;
2124        } else if (isRw2Format(signatureCheckBytes)) {
2125            return IMAGE_TYPE_RW2;
2126        }
2127        // Certain file formats (PEF) are identified in readImageFileDirectory()
2128        return IMAGE_TYPE_UNKNOWN;
2129    }
2130
2131    /**
2132     * This method looks at the first 3 bytes to determine if this file is a JPEG file.
2133     * See http://www.media.mit.edu/pia/Research/deepview/exif.html, "JPEG format and Marker"
2134     */
2135    private static boolean isJpegFormat(byte[] signatureCheckBytes) throws IOException {
2136        for (int i = 0; i < JPEG_SIGNATURE.length; i++) {
2137            if (signatureCheckBytes[i] != JPEG_SIGNATURE[i]) {
2138                return false;
2139            }
2140        }
2141        return true;
2142    }
2143
2144    /**
2145     * This method looks at the first 15 bytes to determine if this file is a RAF file.
2146     * There is no official specification for RAF files from Fuji, but there is an online archive of
2147     * image file specifications:
2148     * http://fileformats.archiveteam.org/wiki/Fujifilm_RAF
2149     */
2150    private boolean isRafFormat(byte[] signatureCheckBytes) throws IOException {
2151        byte[] rafSignatureBytes = RAF_SIGNATURE.getBytes();
2152        for (int i = 0; i < rafSignatureBytes.length; i++) {
2153            if (signatureCheckBytes[i] != rafSignatureBytes[i]) {
2154                return false;
2155            }
2156        }
2157        return true;
2158    }
2159
2160    private boolean isHeifFormat(byte[] signatureCheckBytes) throws IOException {
2161        ByteOrderedDataInputStream signatureInputStream = null;
2162        try {
2163            signatureInputStream = new ByteOrderedDataInputStream(signatureCheckBytes);
2164            signatureInputStream.setByteOrder(ByteOrder.BIG_ENDIAN);
2165
2166            long chunkSize = signatureInputStream.readInt();
2167            byte[] chunkType = new byte[4];
2168            signatureInputStream.read(chunkType);
2169
2170            if (!Arrays.equals(chunkType, HEIF_TYPE_FTYP)) {
2171                return false;
2172            }
2173
2174            long chunkDataOffset = 8;
2175            if (chunkSize == 1) {
2176                // This indicates that the next 8 bytes represent the chunk size,
2177                // and chunk data comes after that.
2178                chunkSize = signatureInputStream.readLong();
2179                if (chunkSize < 16) {
2180                    // The smallest valid chunk is 16 bytes long in this case.
2181                    return false;
2182                }
2183                chunkDataOffset += 8;
2184            }
2185
2186            // only sniff up to signatureCheckBytes.length
2187            if (chunkSize > signatureCheckBytes.length) {
2188                chunkSize = signatureCheckBytes.length;
2189            }
2190
2191            long chunkDataSize = chunkSize - chunkDataOffset;
2192
2193            // It should at least have major brand (4-byte) and minor version (4-byte).
2194            // The rest of the chunk (if any) is a list of (4-byte) compatible brands.
2195            if (chunkDataSize < 8) {
2196                return false;
2197            }
2198
2199            byte[] brand = new byte[4];
2200            boolean isMif1 = false;
2201            boolean isHeic = false;
2202            for (long i = 0; i < chunkDataSize / 4;  ++i) {
2203                if (signatureInputStream.read(brand) != brand.length) {
2204                    return false;
2205                }
2206                if (i == 1) {
2207                    // Skip this index, it refers to the minorVersion, not a brand.
2208                    continue;
2209                }
2210                if (Arrays.equals(brand, HEIF_BRAND_MIF1)) {
2211                    isMif1 = true;
2212                } else if (Arrays.equals(brand, HEIF_BRAND_HEIC)) {
2213                    isHeic = true;
2214                }
2215                if (isMif1 && isHeic) {
2216                    return true;
2217                }
2218            }
2219        } catch (Exception e) {
2220            if (DEBUG) {
2221                Log.d(TAG, "Exception parsing HEIF file type box.", e);
2222            }
2223        } finally {
2224            if (signatureInputStream != null) {
2225                signatureInputStream.close();
2226                signatureInputStream = null;
2227            }
2228        }
2229        return false;
2230    }
2231
2232    /**
2233     * ORF has a similar structure to TIFF but it contains a different signature at the TIFF Header.
2234     * This method looks at the 2 bytes following the Byte Order bytes to determine if this file is
2235     * an ORF file.
2236     * There is no official specification for ORF files from Olympus, but there is an online archive
2237     * of image file specifications:
2238     * http://fileformats.archiveteam.org/wiki/Olympus_ORF
2239     */
2240    private boolean isOrfFormat(byte[] signatureCheckBytes) throws IOException {
2241        ByteOrderedDataInputStream signatureInputStream =
2242                new ByteOrderedDataInputStream(signatureCheckBytes);
2243        // Read byte order
2244        mExifByteOrder = readByteOrder(signatureInputStream);
2245        // Set byte order
2246        signatureInputStream.setByteOrder(mExifByteOrder);
2247
2248        short orfSignature = signatureInputStream.readShort();
2249        if (orfSignature == ORF_SIGNATURE_1 || orfSignature == ORF_SIGNATURE_2) {
2250            return true;
2251        }
2252        return false;
2253    }
2254
2255    /**
2256     * RW2 is TIFF-based, but stores 0x55 signature byte instead of 0x42 at the header
2257     * See http://lclevy.free.fr/raw/
2258     */
2259    private boolean isRw2Format(byte[] signatureCheckBytes) throws IOException {
2260        ByteOrderedDataInputStream signatureInputStream =
2261                new ByteOrderedDataInputStream(signatureCheckBytes);
2262        // Read byte order
2263        mExifByteOrder = readByteOrder(signatureInputStream);
2264        // Set byte order
2265        signatureInputStream.setByteOrder(mExifByteOrder);
2266
2267        short signatureByte = signatureInputStream.readShort();
2268        if (signatureByte == RW2_SIGNATURE) {
2269            return true;
2270        }
2271        return false;
2272    }
2273
2274    /**
2275     * Loads EXIF attributes from a JPEG input stream.
2276     *
2277     * @param in The input stream that starts with the JPEG data.
2278     * @param jpegOffset The offset value in input stream for JPEG data.
2279     * @param imageType The image type from which to retrieve metadata. Use IFD_TYPE_PRIMARY for
2280     *                   primary image, IFD_TYPE_PREVIEW for preview image, and
2281     *                   IFD_TYPE_THUMBNAIL for thumbnail image.
2282     * @throws IOException If the data contains invalid JPEG markers, offsets, or length values.
2283     */
2284    private void getJpegAttributes(ByteOrderedDataInputStream in, int jpegOffset, int imageType)
2285            throws IOException {
2286        // See JPEG File Interchange Format Specification, "JFIF Specification"
2287        if (DEBUG) {
2288            Log.d(TAG, "getJpegAttributes starting with: " + in);
2289        }
2290
2291        // JPEG uses Big Endian by default. See https://people.cs.umass.edu/~verts/cs32/endian.html
2292        in.setByteOrder(ByteOrder.BIG_ENDIAN);
2293
2294        // Skip to JPEG data
2295        in.seek(jpegOffset);
2296        int bytesRead = jpegOffset;
2297
2298        byte marker;
2299        if ((marker = in.readByte()) != MARKER) {
2300            throw new IOException("Invalid marker: " + Integer.toHexString(marker & 0xff));
2301        }
2302        ++bytesRead;
2303        if (in.readByte() != MARKER_SOI) {
2304            throw new IOException("Invalid marker: " + Integer.toHexString(marker & 0xff));
2305        }
2306        ++bytesRead;
2307        while (true) {
2308            marker = in.readByte();
2309            if (marker != MARKER) {
2310                throw new IOException("Invalid marker:" + Integer.toHexString(marker & 0xff));
2311            }
2312            ++bytesRead;
2313            marker = in.readByte();
2314            if (DEBUG) {
2315                Log.d(TAG, "Found JPEG segment indicator: " + Integer.toHexString(marker & 0xff));
2316            }
2317            ++bytesRead;
2318
2319            // EOI indicates the end of an image and in case of SOS, JPEG image stream starts and
2320            // the image data will terminate right after.
2321            if (marker == MARKER_EOI || marker == MARKER_SOS) {
2322                break;
2323            }
2324            int length = in.readUnsignedShort() - 2;
2325            bytesRead += 2;
2326            if (DEBUG) {
2327                Log.d(TAG, "JPEG segment: " + Integer.toHexString(marker & 0xff) + " (length: "
2328                        + (length + 2) + ")");
2329            }
2330            if (length < 0) {
2331                throw new IOException("Invalid length");
2332            }
2333            switch (marker) {
2334                case MARKER_APP1: {
2335                    if (DEBUG) {
2336                        Log.d(TAG, "MARKER_APP1");
2337                    }
2338                    if (length < 6) {
2339                        // Skip if it's not an EXIF APP1 segment.
2340                        break;
2341                    }
2342                    byte[] identifier = new byte[6];
2343                    if (in.read(identifier) != 6) {
2344                        throw new IOException("Invalid exif");
2345                    }
2346                    bytesRead += 6;
2347                    length -= 6;
2348                    if (!Arrays.equals(identifier, IDENTIFIER_EXIF_APP1)) {
2349                        // Skip if it's not an EXIF APP1 segment.
2350                        break;
2351                    }
2352                    if (length <= 0) {
2353                        throw new IOException("Invalid exif");
2354                    }
2355                    if (DEBUG) {
2356                        Log.d(TAG, "readExifSegment with a byte array (length: " + length + ")");
2357                    }
2358                    // Save offset values for createJpegThumbnailBitmap() function
2359                    mExifOffset = bytesRead;
2360
2361                    byte[] bytes = new byte[length];
2362                    if (in.read(bytes) != length) {
2363                        throw new IOException("Invalid exif");
2364                    }
2365                    bytesRead += length;
2366                    length = 0;
2367
2368                    readExifSegment(bytes, imageType);
2369                    break;
2370                }
2371
2372                case MARKER_COM: {
2373                    byte[] bytes = new byte[length];
2374                    if (in.read(bytes) != length) {
2375                        throw new IOException("Invalid exif");
2376                    }
2377                    length = 0;
2378                    if (getAttribute(TAG_USER_COMMENT) == null) {
2379                        mAttributes[IFD_TYPE_EXIF].put(TAG_USER_COMMENT, ExifAttribute.createString(
2380                                new String(bytes, ASCII)));
2381                    }
2382                    break;
2383                }
2384
2385                case MARKER_SOF0:
2386                case MARKER_SOF1:
2387                case MARKER_SOF2:
2388                case MARKER_SOF3:
2389                case MARKER_SOF5:
2390                case MARKER_SOF6:
2391                case MARKER_SOF7:
2392                case MARKER_SOF9:
2393                case MARKER_SOF10:
2394                case MARKER_SOF11:
2395                case MARKER_SOF13:
2396                case MARKER_SOF14:
2397                case MARKER_SOF15: {
2398                    if (in.skipBytes(1) != 1) {
2399                        throw new IOException("Invalid SOFx");
2400                    }
2401                    mAttributes[imageType].put(TAG_IMAGE_LENGTH, ExifAttribute.createULong(
2402                            in.readUnsignedShort(), mExifByteOrder));
2403                    mAttributes[imageType].put(TAG_IMAGE_WIDTH, ExifAttribute.createULong(
2404                            in.readUnsignedShort(), mExifByteOrder));
2405                    length -= 5;
2406                    break;
2407                }
2408
2409                default: {
2410                    break;
2411                }
2412            }
2413            if (length < 0) {
2414                throw new IOException("Invalid length");
2415            }
2416            if (in.skipBytes(length) != length) {
2417                throw new IOException("Invalid JPEG segment");
2418            }
2419            bytesRead += length;
2420        }
2421        // Restore original byte order
2422        in.setByteOrder(mExifByteOrder);
2423    }
2424
2425    private void getRawAttributes(ByteOrderedDataInputStream in) throws IOException {
2426        // Parse TIFF Headers. See JEITA CP-3451C Section 4.5.2. Table 1.
2427        parseTiffHeaders(in, in.available());
2428
2429        // Read TIFF image file directories. See JEITA CP-3451C Section 4.5.2. Figure 6.
2430        readImageFileDirectory(in, IFD_TYPE_PRIMARY);
2431
2432        // Update ImageLength/Width tags for all image data.
2433        updateImageSizeValues(in, IFD_TYPE_PRIMARY);
2434        updateImageSizeValues(in, IFD_TYPE_PREVIEW);
2435        updateImageSizeValues(in, IFD_TYPE_THUMBNAIL);
2436
2437        // Check if each image data is in valid position.
2438        validateImages(in);
2439
2440        if (mMimeType == IMAGE_TYPE_PEF) {
2441            // PEF files contain a MakerNote data, which contains the data for ColorSpace tag.
2442            // See http://lclevy.free.fr/raw/ and piex.cc PefGetPreviewData()
2443            ExifAttribute makerNoteAttribute =
2444                    (ExifAttribute) mAttributes[IFD_TYPE_EXIF].get(TAG_MAKER_NOTE);
2445            if (makerNoteAttribute != null) {
2446                // Create an ordered DataInputStream for MakerNote
2447                ByteOrderedDataInputStream makerNoteDataInputStream =
2448                        new ByteOrderedDataInputStream(makerNoteAttribute.bytes);
2449                makerNoteDataInputStream.setByteOrder(mExifByteOrder);
2450
2451                // Seek to MakerNote data
2452                makerNoteDataInputStream.seek(PEF_MAKER_NOTE_SKIP_SIZE);
2453
2454                // Read IFD data from MakerNote
2455                readImageFileDirectory(makerNoteDataInputStream, IFD_TYPE_PEF);
2456
2457                // Update ColorSpace tag
2458                ExifAttribute colorSpaceAttribute =
2459                        (ExifAttribute) mAttributes[IFD_TYPE_PEF].get(TAG_COLOR_SPACE);
2460                if (colorSpaceAttribute != null) {
2461                    mAttributes[IFD_TYPE_EXIF].put(TAG_COLOR_SPACE, colorSpaceAttribute);
2462                }
2463            }
2464        }
2465    }
2466
2467    /**
2468     * RAF files contains a JPEG and a CFA data.
2469     * The JPEG contains two images, a preview and a thumbnail, while the CFA contains a RAW image.
2470     * This method looks at the first 160 bytes of a RAF file to retrieve the offset and length
2471     * values for the JPEG and CFA data.
2472     * Using that data, it parses the JPEG data to retrieve the preview and thumbnail image data,
2473     * then parses the CFA metadata to retrieve the primary image length/width values.
2474     * For data format details, see http://fileformats.archiveteam.org/wiki/Fujifilm_RAF
2475     */
2476    private void getRafAttributes(ByteOrderedDataInputStream in) throws IOException {
2477        // Retrieve offset & length values
2478        in.skipBytes(RAF_OFFSET_TO_JPEG_IMAGE_OFFSET);
2479        byte[] jpegOffsetBytes = new byte[4];
2480        byte[] cfaHeaderOffsetBytes = new byte[4];
2481        in.read(jpegOffsetBytes);
2482        // Skip JPEG length value since it is not needed
2483        in.skipBytes(RAF_JPEG_LENGTH_VALUE_SIZE);
2484        in.read(cfaHeaderOffsetBytes);
2485        int rafJpegOffset = ByteBuffer.wrap(jpegOffsetBytes).getInt();
2486        int rafCfaHeaderOffset = ByteBuffer.wrap(cfaHeaderOffsetBytes).getInt();
2487
2488        // Retrieve JPEG image metadata
2489        getJpegAttributes(in, rafJpegOffset, IFD_TYPE_PREVIEW);
2490
2491        // Skip to CFA header offset.
2492        in.seek(rafCfaHeaderOffset);
2493
2494        // Retrieve primary image length/width values, if TAG_RAF_IMAGE_SIZE exists
2495        in.setByteOrder(ByteOrder.BIG_ENDIAN);
2496        int numberOfDirectoryEntry = in.readInt();
2497        if (DEBUG) {
2498            Log.d(TAG, "numberOfDirectoryEntry: " + numberOfDirectoryEntry);
2499        }
2500        // CFA stores some metadata about the RAW image. Since CFA uses proprietary tags, can only
2501        // find and retrieve image size information tags, while skipping others.
2502        // See piex.cc RafGetDimension()
2503        for (int i = 0; i < numberOfDirectoryEntry; ++i) {
2504            int tagNumber = in.readUnsignedShort();
2505            int numberOfBytes = in.readUnsignedShort();
2506            if (tagNumber == TAG_RAF_IMAGE_SIZE.number) {
2507                int imageLength = in.readShort();
2508                int imageWidth = in.readShort();
2509                ExifAttribute imageLengthAttribute =
2510                        ExifAttribute.createUShort(imageLength, mExifByteOrder);
2511                ExifAttribute imageWidthAttribute =
2512                        ExifAttribute.createUShort(imageWidth, mExifByteOrder);
2513                mAttributes[IFD_TYPE_PRIMARY].put(TAG_IMAGE_LENGTH, imageLengthAttribute);
2514                mAttributes[IFD_TYPE_PRIMARY].put(TAG_IMAGE_WIDTH, imageWidthAttribute);
2515                if (DEBUG) {
2516                    Log.d(TAG, "Updated to length: " + imageLength + ", width: " + imageWidth);
2517                }
2518                return;
2519            }
2520            in.skipBytes(numberOfBytes);
2521        }
2522    }
2523
2524    private void getHeifAttributes(ByteOrderedDataInputStream in) throws IOException {
2525        MediaMetadataRetriever retriever = new MediaMetadataRetriever();
2526        try {
2527            if (mSeekableFileDescriptor != null) {
2528                retriever.setDataSource(mSeekableFileDescriptor);
2529            } else {
2530                retriever.setDataSource(new MediaDataSource() {
2531                    long mPosition;
2532
2533                    @Override
2534                    public void close() throws IOException {}
2535
2536                    @Override
2537                    public int readAt(long position, byte[] buffer, int offset, int size)
2538                            throws IOException {
2539                        if (size == 0) {
2540                            return 0;
2541                        }
2542                        if (position < 0) {
2543                            return -1;
2544                        }
2545                        if (mPosition != position) {
2546                            in.seek(position);
2547                            mPosition = position;
2548                        }
2549
2550                        int bytesRead = in.read(buffer, offset, size);
2551                        if (bytesRead < 0) {
2552                            mPosition = -1; // need to seek on next read
2553                            return -1;
2554                        }
2555
2556                        mPosition += bytesRead;
2557                        return bytesRead;
2558                    }
2559
2560                    @Override
2561                    public long getSize() throws IOException {
2562                        return -1;
2563                    }
2564                });
2565            }
2566
2567            String hasImage = retriever.extractMetadata(
2568                    MediaMetadataRetriever.METADATA_KEY_HAS_IMAGE);
2569            String hasVideo = retriever.extractMetadata(
2570                    MediaMetadataRetriever.METADATA_KEY_HAS_VIDEO);
2571
2572            String width = null;
2573            String height = null;
2574            String rotation = null;
2575            final String METADATA_VALUE_YES = "yes";
2576            // If the file has both image and video, prefer image info over video info.
2577            // App querying ExifInterface is most likely using the bitmap path which
2578            // picks the image first.
2579            if (METADATA_VALUE_YES.equals(hasImage)) {
2580                width = retriever.extractMetadata(
2581                        MediaMetadataRetriever.METADATA_KEY_IMAGE_WIDTH);
2582                height = retriever.extractMetadata(
2583                        MediaMetadataRetriever.METADATA_KEY_IMAGE_HEIGHT);
2584                rotation = retriever.extractMetadata(
2585                        MediaMetadataRetriever.METADATA_KEY_IMAGE_ROTATION);
2586            } else if (METADATA_VALUE_YES.equals(hasVideo)) {
2587                width = retriever.extractMetadata(
2588                        MediaMetadataRetriever.METADATA_KEY_VIDEO_WIDTH);
2589                height = retriever.extractMetadata(
2590                        MediaMetadataRetriever.METADATA_KEY_VIDEO_HEIGHT);
2591                rotation = retriever.extractMetadata(
2592                        MediaMetadataRetriever.METADATA_KEY_VIDEO_ROTATION);
2593            }
2594
2595            if (width != null) {
2596                mAttributes[IFD_TYPE_PRIMARY].put(TAG_IMAGE_WIDTH,
2597                        ExifAttribute.createUShort(Integer.parseInt(width), mExifByteOrder));
2598            }
2599
2600            if (height != null) {
2601                mAttributes[IFD_TYPE_PRIMARY].put(TAG_IMAGE_LENGTH,
2602                        ExifAttribute.createUShort(Integer.parseInt(height), mExifByteOrder));
2603            }
2604
2605            if (rotation != null) {
2606                int orientation = ExifInterface.ORIENTATION_NORMAL;
2607
2608                // all rotation angles in CW
2609                switch (Integer.parseInt(rotation)) {
2610                    case 90:
2611                        orientation = ExifInterface.ORIENTATION_ROTATE_90;
2612                        break;
2613                    case 180:
2614                        orientation = ExifInterface.ORIENTATION_ROTATE_180;
2615                        break;
2616                    case 270:
2617                        orientation = ExifInterface.ORIENTATION_ROTATE_270;
2618                        break;
2619                }
2620
2621                mAttributes[IFD_TYPE_PRIMARY].put(TAG_ORIENTATION,
2622                        ExifAttribute.createUShort(orientation, mExifByteOrder));
2623            }
2624
2625            if (DEBUG) {
2626                Log.d(TAG, "Heif meta: " + width + "x" + height + ", rotation " + rotation);
2627            }
2628        } finally {
2629            retriever.release();
2630        }
2631    }
2632
2633    /**
2634     * ORF files contains a primary image data and a MakerNote data that contains preview/thumbnail
2635     * images. Both data takes the form of IFDs and can therefore be read with the
2636     * readImageFileDirectory() method.
2637     * This method reads all the necessary data and updates the primary/preview/thumbnail image
2638     * information according to the GetOlympusPreviewImage() method in piex.cc.
2639     * For data format details, see the following:
2640     * http://fileformats.archiveteam.org/wiki/Olympus_ORF
2641     * https://libopenraw.freedesktop.org/wiki/Olympus_ORF
2642     */
2643    private void getOrfAttributes(ByteOrderedDataInputStream in) throws IOException {
2644        // Retrieve primary image data
2645        // Other Exif data will be located in the Makernote.
2646        getRawAttributes(in);
2647
2648        // Additionally retrieve preview/thumbnail information from MakerNote tag, which contains
2649        // proprietary tags and therefore does not have offical documentation
2650        // See GetOlympusPreviewImage() in piex.cc & http://www.exiv2.org/tags-olympus.html
2651        ExifAttribute makerNoteAttribute =
2652                (ExifAttribute) mAttributes[IFD_TYPE_EXIF].get(TAG_MAKER_NOTE);
2653        if (makerNoteAttribute != null) {
2654            // Create an ordered DataInputStream for MakerNote
2655            ByteOrderedDataInputStream makerNoteDataInputStream =
2656                    new ByteOrderedDataInputStream(makerNoteAttribute.bytes);
2657            makerNoteDataInputStream.setByteOrder(mExifByteOrder);
2658
2659            // There are two types of headers for Olympus MakerNotes
2660            // See http://www.exiv2.org/makernote.html#R1
2661            byte[] makerNoteHeader1Bytes = new byte[ORF_MAKER_NOTE_HEADER_1.length];
2662            makerNoteDataInputStream.readFully(makerNoteHeader1Bytes);
2663            makerNoteDataInputStream.seek(0);
2664            byte[] makerNoteHeader2Bytes = new byte[ORF_MAKER_NOTE_HEADER_2.length];
2665            makerNoteDataInputStream.readFully(makerNoteHeader2Bytes);
2666            // Skip the corresponding amount of bytes for each header type
2667            if (Arrays.equals(makerNoteHeader1Bytes, ORF_MAKER_NOTE_HEADER_1)) {
2668                makerNoteDataInputStream.seek(ORF_MAKER_NOTE_HEADER_1_SIZE);
2669            } else if (Arrays.equals(makerNoteHeader2Bytes, ORF_MAKER_NOTE_HEADER_2)) {
2670                makerNoteDataInputStream.seek(ORF_MAKER_NOTE_HEADER_2_SIZE);
2671            }
2672
2673            // Read IFD data from MakerNote
2674            readImageFileDirectory(makerNoteDataInputStream, IFD_TYPE_ORF_MAKER_NOTE);
2675
2676            // Retrieve & update preview image offset & length values
2677            ExifAttribute imageLengthAttribute = (ExifAttribute)
2678                    mAttributes[IFD_TYPE_ORF_CAMERA_SETTINGS].get(TAG_ORF_PREVIEW_IMAGE_START);
2679            ExifAttribute bitsPerSampleAttribute = (ExifAttribute)
2680                    mAttributes[IFD_TYPE_ORF_CAMERA_SETTINGS].get(TAG_ORF_PREVIEW_IMAGE_LENGTH);
2681
2682            if (imageLengthAttribute != null && bitsPerSampleAttribute != null) {
2683                mAttributes[IFD_TYPE_PREVIEW].put(TAG_JPEG_INTERCHANGE_FORMAT,
2684                        imageLengthAttribute);
2685                mAttributes[IFD_TYPE_PREVIEW].put(TAG_JPEG_INTERCHANGE_FORMAT_LENGTH,
2686                        bitsPerSampleAttribute);
2687            }
2688
2689            // TODO: Check this behavior in other ORF files
2690            // Retrieve primary image length & width values
2691            // See piex.cc GetOlympusPreviewImage()
2692            ExifAttribute aspectFrameAttribute = (ExifAttribute)
2693                    mAttributes[IFD_TYPE_ORF_IMAGE_PROCESSING].get(TAG_ORF_ASPECT_FRAME);
2694            if (aspectFrameAttribute != null) {
2695                int[] aspectFrameValues = new int[4];
2696                aspectFrameValues = (int[]) aspectFrameAttribute.getValue(mExifByteOrder);
2697                if (aspectFrameValues[2] > aspectFrameValues[0] &&
2698                        aspectFrameValues[3] > aspectFrameValues[1]) {
2699                    int primaryImageWidth = aspectFrameValues[2] - aspectFrameValues[0] + 1;
2700                    int primaryImageLength = aspectFrameValues[3] - aspectFrameValues[1] + 1;
2701                    // Swap width & length values
2702                    if (primaryImageWidth < primaryImageLength) {
2703                        primaryImageWidth += primaryImageLength;
2704                        primaryImageLength = primaryImageWidth - primaryImageLength;
2705                        primaryImageWidth -= primaryImageLength;
2706                    }
2707                    ExifAttribute primaryImageWidthAttribute =
2708                            ExifAttribute.createUShort(primaryImageWidth, mExifByteOrder);
2709                    ExifAttribute primaryImageLengthAttribute =
2710                            ExifAttribute.createUShort(primaryImageLength, mExifByteOrder);
2711
2712                    mAttributes[IFD_TYPE_PRIMARY].put(TAG_IMAGE_WIDTH, primaryImageWidthAttribute);
2713                    mAttributes[IFD_TYPE_PRIMARY].put(TAG_IMAGE_LENGTH, primaryImageLengthAttribute);
2714                }
2715            }
2716        }
2717    }
2718
2719    // RW2 contains the primary image data in IFD0 and the preview and/or thumbnail image data in
2720    // the JpgFromRaw tag
2721    // See https://libopenraw.freedesktop.org/wiki/Panasonic_RAW/ and piex.cc Rw2GetPreviewData()
2722    private void getRw2Attributes(ByteOrderedDataInputStream in) throws IOException {
2723        // Retrieve primary image data
2724        getRawAttributes(in);
2725
2726        // Retrieve preview and/or thumbnail image data
2727        ExifAttribute jpgFromRawAttribute =
2728                (ExifAttribute) mAttributes[IFD_TYPE_PRIMARY].get(TAG_RW2_JPG_FROM_RAW);
2729        if (jpgFromRawAttribute != null) {
2730            getJpegAttributes(in, mRw2JpgFromRawOffset, IFD_TYPE_PREVIEW);
2731        }
2732
2733        // Set ISO tag value if necessary
2734        ExifAttribute rw2IsoAttribute =
2735                (ExifAttribute) mAttributes[IFD_TYPE_PRIMARY].get(TAG_RW2_ISO);
2736        ExifAttribute exifIsoAttribute =
2737                (ExifAttribute) mAttributes[IFD_TYPE_EXIF].get(TAG_ISO_SPEED_RATINGS);
2738        if (rw2IsoAttribute != null && exifIsoAttribute == null) {
2739            // Place this attribute only if it doesn't exist
2740            mAttributes[IFD_TYPE_EXIF].put(TAG_ISO_SPEED_RATINGS, rw2IsoAttribute);
2741        }
2742    }
2743
2744    // Stores a new JPEG image with EXIF attributes into a given output stream.
2745    private void saveJpegAttributes(InputStream inputStream, OutputStream outputStream)
2746            throws IOException {
2747        // See JPEG File Interchange Format Specification, "JFIF Specification"
2748        if (DEBUG) {
2749            Log.d(TAG, "saveJpegAttributes starting with (inputStream: " + inputStream
2750                    + ", outputStream: " + outputStream + ")");
2751        }
2752        DataInputStream dataInputStream = new DataInputStream(inputStream);
2753        ByteOrderedDataOutputStream dataOutputStream =
2754                new ByteOrderedDataOutputStream(outputStream, ByteOrder.BIG_ENDIAN);
2755        if (dataInputStream.readByte() != MARKER) {
2756            throw new IOException("Invalid marker");
2757        }
2758        dataOutputStream.writeByte(MARKER);
2759        if (dataInputStream.readByte() != MARKER_SOI) {
2760            throw new IOException("Invalid marker");
2761        }
2762        dataOutputStream.writeByte(MARKER_SOI);
2763
2764        // Write EXIF APP1 segment
2765        dataOutputStream.writeByte(MARKER);
2766        dataOutputStream.writeByte(MARKER_APP1);
2767        writeExifSegment(dataOutputStream, 6);
2768
2769        byte[] bytes = new byte[4096];
2770
2771        while (true) {
2772            byte marker = dataInputStream.readByte();
2773            if (marker != MARKER) {
2774                throw new IOException("Invalid marker");
2775            }
2776            marker = dataInputStream.readByte();
2777            switch (marker) {
2778                case MARKER_APP1: {
2779                    int length = dataInputStream.readUnsignedShort() - 2;
2780                    if (length < 0) {
2781                        throw new IOException("Invalid length");
2782                    }
2783                    byte[] identifier = new byte[6];
2784                    if (length >= 6) {
2785                        if (dataInputStream.read(identifier) != 6) {
2786                            throw new IOException("Invalid exif");
2787                        }
2788                        if (Arrays.equals(identifier, IDENTIFIER_EXIF_APP1)) {
2789                            // Skip the original EXIF APP1 segment.
2790                            if (dataInputStream.skipBytes(length - 6) != length - 6) {
2791                                throw new IOException("Invalid length");
2792                            }
2793                            break;
2794                        }
2795                    }
2796                    // Copy non-EXIF APP1 segment.
2797                    dataOutputStream.writeByte(MARKER);
2798                    dataOutputStream.writeByte(marker);
2799                    dataOutputStream.writeUnsignedShort(length + 2);
2800                    if (length >= 6) {
2801                        length -= 6;
2802                        dataOutputStream.write(identifier);
2803                    }
2804                    int read;
2805                    while (length > 0 && (read = dataInputStream.read(
2806                            bytes, 0, Math.min(length, bytes.length))) >= 0) {
2807                        dataOutputStream.write(bytes, 0, read);
2808                        length -= read;
2809                    }
2810                    break;
2811                }
2812                case MARKER_EOI:
2813                case MARKER_SOS: {
2814                    dataOutputStream.writeByte(MARKER);
2815                    dataOutputStream.writeByte(marker);
2816                    // Copy all the remaining data
2817                    Streams.copy(dataInputStream, dataOutputStream);
2818                    return;
2819                }
2820                default: {
2821                    // Copy JPEG segment
2822                    dataOutputStream.writeByte(MARKER);
2823                    dataOutputStream.writeByte(marker);
2824                    int length = dataInputStream.readUnsignedShort();
2825                    dataOutputStream.writeUnsignedShort(length);
2826                    length -= 2;
2827                    if (length < 0) {
2828                        throw new IOException("Invalid length");
2829                    }
2830                    int read;
2831                    while (length > 0 && (read = dataInputStream.read(
2832                            bytes, 0, Math.min(length, bytes.length))) >= 0) {
2833                        dataOutputStream.write(bytes, 0, read);
2834                        length -= read;
2835                    }
2836                    break;
2837                }
2838            }
2839        }
2840    }
2841
2842    // Reads the given EXIF byte area and save its tag data into attributes.
2843    private void readExifSegment(byte[] exifBytes, int imageType) throws IOException {
2844        ByteOrderedDataInputStream dataInputStream =
2845                new ByteOrderedDataInputStream(exifBytes);
2846
2847        // Parse TIFF Headers. See JEITA CP-3451C Section 4.5.2. Table 1.
2848        parseTiffHeaders(dataInputStream, exifBytes.length);
2849
2850        // Read TIFF image file directories. See JEITA CP-3451C Section 4.5.2. Figure 6.
2851        readImageFileDirectory(dataInputStream, imageType);
2852    }
2853
2854    private void addDefaultValuesForCompatibility() {
2855        // If DATETIME tag has no value, then set the value to DATETIME_ORIGINAL tag's.
2856        String valueOfDateTimeOriginal = getAttribute(TAG_DATETIME_ORIGINAL);
2857        if (valueOfDateTimeOriginal != null && getAttribute(TAG_DATETIME) == null) {
2858            mAttributes[IFD_TYPE_PRIMARY].put(TAG_DATETIME,
2859                    ExifAttribute.createString(valueOfDateTimeOriginal));
2860        }
2861
2862        // Add the default value.
2863        if (getAttribute(TAG_IMAGE_WIDTH) == null) {
2864            mAttributes[IFD_TYPE_PRIMARY].put(TAG_IMAGE_WIDTH,
2865                    ExifAttribute.createULong(0, mExifByteOrder));
2866        }
2867        if (getAttribute(TAG_IMAGE_LENGTH) == null) {
2868            mAttributes[IFD_TYPE_PRIMARY].put(TAG_IMAGE_LENGTH,
2869                    ExifAttribute.createULong(0, mExifByteOrder));
2870        }
2871        if (getAttribute(TAG_ORIENTATION) == null) {
2872            mAttributes[IFD_TYPE_PRIMARY].put(TAG_ORIENTATION,
2873                    ExifAttribute.createUShort(0, mExifByteOrder));
2874        }
2875        if (getAttribute(TAG_LIGHT_SOURCE) == null) {
2876            mAttributes[IFD_TYPE_EXIF].put(TAG_LIGHT_SOURCE,
2877                    ExifAttribute.createULong(0, mExifByteOrder));
2878        }
2879    }
2880
2881    private ByteOrder readByteOrder(ByteOrderedDataInputStream dataInputStream)
2882            throws IOException {
2883        // Read byte order.
2884        short byteOrder = dataInputStream.readShort();
2885        switch (byteOrder) {
2886            case BYTE_ALIGN_II:
2887                if (DEBUG) {
2888                    Log.d(TAG, "readExifSegment: Byte Align II");
2889                }
2890                return ByteOrder.LITTLE_ENDIAN;
2891            case BYTE_ALIGN_MM:
2892                if (DEBUG) {
2893                    Log.d(TAG, "readExifSegment: Byte Align MM");
2894                }
2895                return ByteOrder.BIG_ENDIAN;
2896            default:
2897                throw new IOException("Invalid byte order: " + Integer.toHexString(byteOrder));
2898        }
2899    }
2900
2901    private void parseTiffHeaders(ByteOrderedDataInputStream dataInputStream,
2902            int exifBytesLength) throws IOException {
2903        // Read byte order
2904        mExifByteOrder = readByteOrder(dataInputStream);
2905        // Set byte order
2906        dataInputStream.setByteOrder(mExifByteOrder);
2907
2908        // Check start code
2909        int startCode = dataInputStream.readUnsignedShort();
2910        if (mMimeType != IMAGE_TYPE_ORF && mMimeType != IMAGE_TYPE_RW2 && startCode != START_CODE) {
2911            throw new IOException("Invalid start code: " + Integer.toHexString(startCode));
2912        }
2913
2914        // Read and skip to first ifd offset
2915        int firstIfdOffset = dataInputStream.readInt();
2916        if (firstIfdOffset < 8 || firstIfdOffset >= exifBytesLength) {
2917            throw new IOException("Invalid first Ifd offset: " + firstIfdOffset);
2918        }
2919        firstIfdOffset -= 8;
2920        if (firstIfdOffset > 0) {
2921            if (dataInputStream.skipBytes(firstIfdOffset) != firstIfdOffset) {
2922                throw new IOException("Couldn't jump to first Ifd: " + firstIfdOffset);
2923            }
2924        }
2925    }
2926
2927    // Reads image file directory, which is a tag group in EXIF.
2928    private void readImageFileDirectory(ByteOrderedDataInputStream dataInputStream,
2929            @IfdType int ifdType) throws IOException {
2930        if (dataInputStream.mPosition + 2 > dataInputStream.mLength) {
2931            // Return if there is no data from the offset.
2932            return;
2933        }
2934        // See TIFF 6.0 Section 2: TIFF Structure, Figure 1.
2935        short numberOfDirectoryEntry = dataInputStream.readShort();
2936        if (dataInputStream.mPosition + 12 * numberOfDirectoryEntry > dataInputStream.mLength) {
2937            // Return if the size of entries is too big.
2938            return;
2939        }
2940
2941        if (DEBUG) {
2942            Log.d(TAG, "numberOfDirectoryEntry: " + numberOfDirectoryEntry);
2943        }
2944
2945        // See TIFF 6.0 Section 2: TIFF Structure, "Image File Directory".
2946        for (short i = 0; i < numberOfDirectoryEntry; ++i) {
2947            int tagNumber = dataInputStream.readUnsignedShort();
2948            int dataFormat = dataInputStream.readUnsignedShort();
2949            int numberOfComponents = dataInputStream.readInt();
2950            // Next four bytes is for data offset or value.
2951            long nextEntryOffset = dataInputStream.peek() + 4;
2952
2953            // Look up a corresponding tag from tag number
2954            ExifTag tag = (ExifTag) sExifTagMapsForReading[ifdType].get(tagNumber);
2955
2956            if (DEBUG) {
2957                Log.d(TAG, String.format("ifdType: %d, tagNumber: %d, tagName: %s, dataFormat: %d, "
2958                        + "numberOfComponents: %d", ifdType, tagNumber,
2959                        tag != null ? tag.name : null, dataFormat, numberOfComponents));
2960            }
2961
2962            long byteCount = 0;
2963            boolean valid = false;
2964            if (tag == null) {
2965                Log.w(TAG, "Skip the tag entry since tag number is not defined: " + tagNumber);
2966            } else if (dataFormat <= 0 || dataFormat >= IFD_FORMAT_BYTES_PER_FORMAT.length) {
2967                Log.w(TAG, "Skip the tag entry since data format is invalid: " + dataFormat);
2968            } else {
2969                byteCount = (long) numberOfComponents * IFD_FORMAT_BYTES_PER_FORMAT[dataFormat];
2970                if (byteCount < 0 || byteCount > Integer.MAX_VALUE) {
2971                    Log.w(TAG, "Skip the tag entry since the number of components is invalid: "
2972                            + numberOfComponents);
2973                } else {
2974                    valid = true;
2975                }
2976            }
2977            if (!valid) {
2978                dataInputStream.seek(nextEntryOffset);
2979                continue;
2980            }
2981
2982            // Read a value from data field or seek to the value offset which is stored in data
2983            // field if the size of the entry value is bigger than 4.
2984            if (byteCount > 4) {
2985                int offset = dataInputStream.readInt();
2986                if (DEBUG) {
2987                    Log.d(TAG, "seek to data offset: " + offset);
2988                }
2989                if (mMimeType == IMAGE_TYPE_ORF) {
2990                    if (tag.name == TAG_MAKER_NOTE) {
2991                        // Save offset value for reading thumbnail
2992                        mOrfMakerNoteOffset = offset;
2993                    } else if (ifdType == IFD_TYPE_ORF_MAKER_NOTE
2994                            && tag.name == TAG_ORF_THUMBNAIL_IMAGE) {
2995                        // Retrieve & update values for thumbnail offset and length values for ORF
2996                        mOrfThumbnailOffset = offset;
2997                        mOrfThumbnailLength = numberOfComponents;
2998
2999                        ExifAttribute compressionAttribute =
3000                                ExifAttribute.createUShort(DATA_JPEG, mExifByteOrder);
3001                        ExifAttribute jpegInterchangeFormatAttribute =
3002                                ExifAttribute.createULong(mOrfThumbnailOffset, mExifByteOrder);
3003                        ExifAttribute jpegInterchangeFormatLengthAttribute =
3004                                ExifAttribute.createULong(mOrfThumbnailLength, mExifByteOrder);
3005
3006                        mAttributes[IFD_TYPE_THUMBNAIL].put(TAG_COMPRESSION, compressionAttribute);
3007                        mAttributes[IFD_TYPE_THUMBNAIL].put(TAG_JPEG_INTERCHANGE_FORMAT,
3008                                jpegInterchangeFormatAttribute);
3009                        mAttributes[IFD_TYPE_THUMBNAIL].put(TAG_JPEG_INTERCHANGE_FORMAT_LENGTH,
3010                                jpegInterchangeFormatLengthAttribute);
3011                    }
3012                } else if (mMimeType == IMAGE_TYPE_RW2) {
3013                    if (tag.name == TAG_RW2_JPG_FROM_RAW) {
3014                        mRw2JpgFromRawOffset = offset;
3015                    }
3016                }
3017                if (offset + byteCount <= dataInputStream.mLength) {
3018                    dataInputStream.seek(offset);
3019                } else {
3020                    // Skip if invalid data offset.
3021                    Log.w(TAG, "Skip the tag entry since data offset is invalid: " + offset);
3022                    dataInputStream.seek(nextEntryOffset);
3023                    continue;
3024                }
3025            }
3026
3027            // Recursively parse IFD when a IFD pointer tag appears.
3028            Object nextIfdType = sExifPointerTagMap.get(tagNumber);
3029            if (DEBUG) {
3030                Log.d(TAG, "nextIfdType: " + nextIfdType + " byteCount: " + byteCount);
3031            }
3032
3033            if (nextIfdType != null) {
3034                long offset = -1L;
3035                // Get offset from data field
3036                switch (dataFormat) {
3037                    case IFD_FORMAT_USHORT: {
3038                        offset = dataInputStream.readUnsignedShort();
3039                        break;
3040                    }
3041                    case IFD_FORMAT_SSHORT: {
3042                        offset = dataInputStream.readShort();
3043                        break;
3044                    }
3045                    case IFD_FORMAT_ULONG: {
3046                        offset = dataInputStream.readUnsignedInt();
3047                        break;
3048                    }
3049                    case IFD_FORMAT_SLONG:
3050                    case IFD_FORMAT_IFD: {
3051                        offset = dataInputStream.readInt();
3052                        break;
3053                    }
3054                    default: {
3055                        // Nothing to do
3056                        break;
3057                    }
3058                }
3059                if (DEBUG) {
3060                    Log.d(TAG, String.format("Offset: %d, tagName: %s", offset, tag.name));
3061                }
3062                if (offset > 0L && offset < dataInputStream.mLength) {
3063                    dataInputStream.seek(offset);
3064                    readImageFileDirectory(dataInputStream, (int) nextIfdType);
3065                } else {
3066                    Log.w(TAG, "Skip jump into the IFD since its offset is invalid: " + offset);
3067                }
3068
3069                dataInputStream.seek(nextEntryOffset);
3070                continue;
3071            }
3072
3073            byte[] bytes = new byte[(int) byteCount];
3074            dataInputStream.readFully(bytes);
3075            ExifAttribute attribute = new ExifAttribute(dataFormat, numberOfComponents, bytes);
3076            mAttributes[ifdType].put(tag.name, attribute);
3077
3078            // DNG files have a DNG Version tag specifying the version of specifications that the
3079            // image file is following.
3080            // See http://fileformats.archiveteam.org/wiki/DNG
3081            if (tag.name == TAG_DNG_VERSION) {
3082                mMimeType = IMAGE_TYPE_DNG;
3083            }
3084
3085            // PEF files have a Make or Model tag that begins with "PENTAX" or a compression tag
3086            // that is 65535.
3087            // See http://fileformats.archiveteam.org/wiki/Pentax_PEF
3088            if (((tag.name == TAG_MAKE || tag.name == TAG_MODEL)
3089                    && attribute.getStringValue(mExifByteOrder).contains(PEF_SIGNATURE))
3090                    || (tag.name == TAG_COMPRESSION
3091                    && attribute.getIntValue(mExifByteOrder) == 65535)) {
3092                mMimeType = IMAGE_TYPE_PEF;
3093            }
3094
3095            // Seek to next tag offset
3096            if (dataInputStream.peek() != nextEntryOffset) {
3097                dataInputStream.seek(nextEntryOffset);
3098            }
3099        }
3100
3101        if (dataInputStream.peek() + 4 <= dataInputStream.mLength) {
3102            int nextIfdOffset = dataInputStream.readInt();
3103            if (DEBUG) {
3104                Log.d(TAG, String.format("nextIfdOffset: %d", nextIfdOffset));
3105            }
3106            // The next IFD offset needs to be bigger than 8
3107            // since the first IFD offset is at least 8.
3108            if (nextIfdOffset > 8 && nextIfdOffset < dataInputStream.mLength) {
3109                dataInputStream.seek(nextIfdOffset);
3110                if (mAttributes[IFD_TYPE_THUMBNAIL].isEmpty()) {
3111                    // Do not overwrite thumbnail IFD data if it alreay exists.
3112                    readImageFileDirectory(dataInputStream, IFD_TYPE_THUMBNAIL);
3113                } else if (mAttributes[IFD_TYPE_PREVIEW].isEmpty()) {
3114                    readImageFileDirectory(dataInputStream, IFD_TYPE_PREVIEW);
3115                }
3116            }
3117        }
3118    }
3119
3120    /**
3121     * JPEG compressed images do not contain IMAGE_LENGTH & IMAGE_WIDTH tags.
3122     * This value uses JpegInterchangeFormat(JPEG data offset) value, and calls getJpegAttributes()
3123     * to locate SOF(Start of Frame) marker and update the image length & width values.
3124     * See JEITA CP-3451C Table 5 and Section 4.8.1. B.
3125     */
3126    private void retrieveJpegImageSize(ByteOrderedDataInputStream in, int imageType)
3127            throws IOException {
3128        // Check if image already has IMAGE_LENGTH & IMAGE_WIDTH values
3129        ExifAttribute imageLengthAttribute =
3130                (ExifAttribute) mAttributes[imageType].get(TAG_IMAGE_LENGTH);
3131        ExifAttribute imageWidthAttribute =
3132                (ExifAttribute) mAttributes[imageType].get(TAG_IMAGE_WIDTH);
3133
3134        if (imageLengthAttribute == null || imageWidthAttribute == null) {
3135            // Find if offset for JPEG data exists
3136            ExifAttribute jpegInterchangeFormatAttribute =
3137                    (ExifAttribute) mAttributes[imageType].get(TAG_JPEG_INTERCHANGE_FORMAT);
3138            if (jpegInterchangeFormatAttribute != null) {
3139                int jpegInterchangeFormat =
3140                        jpegInterchangeFormatAttribute.getIntValue(mExifByteOrder);
3141
3142                // Searches for SOF marker in JPEG data and updates IMAGE_LENGTH & IMAGE_WIDTH tags
3143                getJpegAttributes(in, jpegInterchangeFormat, imageType);
3144            }
3145        }
3146    }
3147
3148    // Sets thumbnail offset & length attributes based on JpegInterchangeFormat or StripOffsets tags
3149    private void setThumbnailData(ByteOrderedDataInputStream in) throws IOException {
3150        HashMap thumbnailData = mAttributes[IFD_TYPE_THUMBNAIL];
3151
3152        ExifAttribute compressionAttribute =
3153                (ExifAttribute) thumbnailData.get(TAG_COMPRESSION);
3154        if (compressionAttribute != null) {
3155            mThumbnailCompression = compressionAttribute.getIntValue(mExifByteOrder);
3156            switch (mThumbnailCompression) {
3157                case DATA_JPEG: {
3158                    handleThumbnailFromJfif(in, thumbnailData);
3159                    break;
3160                }
3161                case DATA_UNCOMPRESSED:
3162                case DATA_JPEG_COMPRESSED: {
3163                    if (isSupportedDataType(thumbnailData)) {
3164                        handleThumbnailFromStrips(in, thumbnailData);
3165                    }
3166                    break;
3167                }
3168            }
3169        } else {
3170            // Thumbnail data may not contain Compression tag value
3171            handleThumbnailFromJfif(in, thumbnailData);
3172        }
3173    }
3174
3175    // Check JpegInterchangeFormat(JFIF) tags to retrieve thumbnail offset & length values
3176    // and reads the corresponding bytes if stream does not support seek function
3177    private void handleThumbnailFromJfif(ByteOrderedDataInputStream in, HashMap thumbnailData)
3178            throws IOException {
3179        ExifAttribute jpegInterchangeFormatAttribute =
3180                (ExifAttribute) thumbnailData.get(TAG_JPEG_INTERCHANGE_FORMAT);
3181        ExifAttribute jpegInterchangeFormatLengthAttribute =
3182                (ExifAttribute) thumbnailData.get(TAG_JPEG_INTERCHANGE_FORMAT_LENGTH);
3183        if (jpegInterchangeFormatAttribute != null
3184                && jpegInterchangeFormatLengthAttribute != null) {
3185            int thumbnailOffset = jpegInterchangeFormatAttribute.getIntValue(mExifByteOrder);
3186            int thumbnailLength = jpegInterchangeFormatLengthAttribute.getIntValue(mExifByteOrder);
3187
3188            // The following code limits the size of thumbnail size not to overflow EXIF data area.
3189            thumbnailLength = Math.min(thumbnailLength, in.available() - thumbnailOffset);
3190            if (mMimeType == IMAGE_TYPE_JPEG || mMimeType == IMAGE_TYPE_RAF
3191                    || mMimeType == IMAGE_TYPE_RW2) {
3192                thumbnailOffset += mExifOffset;
3193            } else if (mMimeType == IMAGE_TYPE_ORF) {
3194                // Update offset value since RAF files have IFD data preceding MakerNote data.
3195                thumbnailOffset += mOrfMakerNoteOffset;
3196            }
3197            if (DEBUG) {
3198                Log.d(TAG, "Setting thumbnail attributes with offset: " + thumbnailOffset
3199                        + ", length: " + thumbnailLength);
3200            }
3201            if (thumbnailOffset > 0 && thumbnailLength > 0) {
3202                mHasThumbnail = true;
3203                mThumbnailOffset = thumbnailOffset;
3204                mThumbnailLength = thumbnailLength;
3205                mThumbnailCompression = DATA_JPEG;
3206
3207                if (mFilename == null && mAssetInputStream == null
3208                        && mSeekableFileDescriptor == null) {
3209                    // Save the thumbnail in memory if the input doesn't support reading again.
3210                    byte[] thumbnailBytes = new byte[thumbnailLength];
3211                    in.seek(thumbnailOffset);
3212                    in.readFully(thumbnailBytes);
3213                    mThumbnailBytes = thumbnailBytes;
3214                }
3215            }
3216        }
3217    }
3218
3219    // Check StripOffsets & StripByteCounts tags to retrieve thumbnail offset & length values
3220    private void handleThumbnailFromStrips(ByteOrderedDataInputStream in, HashMap thumbnailData)
3221            throws IOException {
3222        ExifAttribute stripOffsetsAttribute =
3223                (ExifAttribute) thumbnailData.get(TAG_STRIP_OFFSETS);
3224        ExifAttribute stripByteCountsAttribute =
3225                (ExifAttribute) thumbnailData.get(TAG_STRIP_BYTE_COUNTS);
3226
3227        if (stripOffsetsAttribute != null && stripByteCountsAttribute != null) {
3228            long[] stripOffsets =
3229                    convertToLongArray(stripOffsetsAttribute.getValue(mExifByteOrder));
3230            long[] stripByteCounts =
3231                    convertToLongArray(stripByteCountsAttribute.getValue(mExifByteOrder));
3232
3233            if (stripOffsets == null) {
3234                Log.w(TAG, "stripOffsets should not be null.");
3235                return;
3236            }
3237            if (stripByteCounts == null) {
3238                Log.w(TAG, "stripByteCounts should not be null.");
3239                return;
3240            }
3241
3242            // Set thumbnail byte array data for non-consecutive strip bytes
3243            byte[] totalStripBytes =
3244                    new byte[(int) Arrays.stream(stripByteCounts).sum()];
3245
3246            int bytesRead = 0;
3247            int bytesAdded = 0;
3248            for (int i = 0; i < stripOffsets.length; i++) {
3249                int stripOffset = (int) stripOffsets[i];
3250                int stripByteCount = (int) stripByteCounts[i];
3251
3252                // Skip to offset
3253                int skipBytes = stripOffset - bytesRead;
3254                if (skipBytes < 0) {
3255                    Log.d(TAG, "Invalid strip offset value");
3256                }
3257                in.seek(skipBytes);
3258                bytesRead += skipBytes;
3259
3260                // Read strip bytes
3261                byte[] stripBytes = new byte[stripByteCount];
3262                in.read(stripBytes);
3263                bytesRead += stripByteCount;
3264
3265                // Add bytes to array
3266                System.arraycopy(stripBytes, 0, totalStripBytes, bytesAdded,
3267                        stripBytes.length);
3268                bytesAdded += stripBytes.length;
3269            }
3270
3271            mHasThumbnail = true;
3272            mThumbnailBytes = totalStripBytes;
3273            mThumbnailLength = totalStripBytes.length;
3274        }
3275    }
3276
3277    // Check if thumbnail data type is currently supported or not
3278    private boolean isSupportedDataType(HashMap thumbnailData) throws IOException {
3279        ExifAttribute bitsPerSampleAttribute =
3280                (ExifAttribute) thumbnailData.get(TAG_BITS_PER_SAMPLE);
3281        if (bitsPerSampleAttribute != null) {
3282            int[] bitsPerSampleValue = (int[]) bitsPerSampleAttribute.getValue(mExifByteOrder);
3283
3284            if (Arrays.equals(BITS_PER_SAMPLE_RGB, bitsPerSampleValue)) {
3285                return true;
3286            }
3287
3288            // See DNG Specification 1.4.0.0. Section 3, Compression.
3289            if (mMimeType == IMAGE_TYPE_DNG) {
3290                ExifAttribute photometricInterpretationAttribute =
3291                        (ExifAttribute) thumbnailData.get(TAG_PHOTOMETRIC_INTERPRETATION);
3292                if (photometricInterpretationAttribute != null) {
3293                    int photometricInterpretationValue
3294                            = photometricInterpretationAttribute.getIntValue(mExifByteOrder);
3295                    if ((photometricInterpretationValue == PHOTOMETRIC_INTERPRETATION_BLACK_IS_ZERO
3296                            && Arrays.equals(bitsPerSampleValue, BITS_PER_SAMPLE_GREYSCALE_2))
3297                            || ((photometricInterpretationValue == PHOTOMETRIC_INTERPRETATION_YCBCR)
3298                            && (Arrays.equals(bitsPerSampleValue, BITS_PER_SAMPLE_RGB)))) {
3299                        return true;
3300                    } else {
3301                        // TODO: Add support for lossless Huffman JPEG data
3302                    }
3303                }
3304            }
3305        }
3306        if (DEBUG) {
3307            Log.d(TAG, "Unsupported data type value");
3308        }
3309        return false;
3310    }
3311
3312    // Returns true if the image length and width values are <= 512.
3313    // See Section 4.8 of http://standardsproposals.bsigroup.com/Home/getPDF/567
3314    private boolean isThumbnail(HashMap map) throws IOException {
3315        ExifAttribute imageLengthAttribute = (ExifAttribute) map.get(TAG_IMAGE_LENGTH);
3316        ExifAttribute imageWidthAttribute = (ExifAttribute) map.get(TAG_IMAGE_WIDTH);
3317
3318        if (imageLengthAttribute != null && imageWidthAttribute != null) {
3319            int imageLengthValue = imageLengthAttribute.getIntValue(mExifByteOrder);
3320            int imageWidthValue = imageWidthAttribute.getIntValue(mExifByteOrder);
3321            if (imageLengthValue <= MAX_THUMBNAIL_SIZE && imageWidthValue <= MAX_THUMBNAIL_SIZE) {
3322                return true;
3323            }
3324        }
3325        return false;
3326    }
3327
3328    // Validate primary, preview, thumbnail image data by comparing image size
3329    private void validateImages(InputStream in) throws IOException {
3330        // Swap images based on size (primary > preview > thumbnail)
3331        swapBasedOnImageSize(IFD_TYPE_PRIMARY, IFD_TYPE_PREVIEW);
3332        swapBasedOnImageSize(IFD_TYPE_PRIMARY, IFD_TYPE_THUMBNAIL);
3333        swapBasedOnImageSize(IFD_TYPE_PREVIEW, IFD_TYPE_THUMBNAIL);
3334
3335        // Check if image has PixelXDimension/PixelYDimension tags, which contain valid image
3336        // sizes, excluding padding at the right end or bottom end of the image to make sure that
3337        // the values are multiples of 64. See JEITA CP-3451C Table 5 and Section 4.8.1. B.
3338        ExifAttribute pixelXDimAttribute =
3339                (ExifAttribute) mAttributes[IFD_TYPE_EXIF].get(TAG_PIXEL_X_DIMENSION);
3340        ExifAttribute pixelYDimAttribute =
3341                (ExifAttribute) mAttributes[IFD_TYPE_EXIF].get(TAG_PIXEL_Y_DIMENSION);
3342        if (pixelXDimAttribute != null && pixelYDimAttribute != null) {
3343            mAttributes[IFD_TYPE_PRIMARY].put(TAG_IMAGE_WIDTH, pixelXDimAttribute);
3344            mAttributes[IFD_TYPE_PRIMARY].put(TAG_IMAGE_LENGTH, pixelYDimAttribute);
3345        }
3346
3347        // Check whether thumbnail image exists and whether preview image satisfies the thumbnail
3348        // image requirements
3349        if (mAttributes[IFD_TYPE_THUMBNAIL].isEmpty()) {
3350            if (isThumbnail(mAttributes[IFD_TYPE_PREVIEW])) {
3351                mAttributes[IFD_TYPE_THUMBNAIL] = mAttributes[IFD_TYPE_PREVIEW];
3352                mAttributes[IFD_TYPE_PREVIEW] = new HashMap();
3353            }
3354        }
3355
3356        // Check if the thumbnail image satisfies the thumbnail size requirements
3357        if (!isThumbnail(mAttributes[IFD_TYPE_THUMBNAIL])) {
3358            Log.d(TAG, "No image meets the size requirements of a thumbnail image.");
3359        }
3360    }
3361
3362    /**
3363     * If image is uncompressed, ImageWidth/Length tags are used to store size info.
3364     * However, uncompressed images often store extra pixels around the edges of the final image,
3365     * which results in larger values for TAG_IMAGE_WIDTH and TAG_IMAGE_LENGTH tags.
3366     * This method corrects those tag values by checking first the values of TAG_DEFAULT_CROP_SIZE
3367     * See DNG Specification 1.4.0.0. Section 4. (DefaultCropSize)
3368     *
3369     * If image is a RW2 file, valid image sizes are stored in SensorBorder tags.
3370     * See tiff_parser.cc GetFullDimension32()
3371     * */
3372    private void updateImageSizeValues(ByteOrderedDataInputStream in, int imageType)
3373            throws IOException {
3374        // Uncompressed image valid image size values
3375        ExifAttribute defaultCropSizeAttribute =
3376                (ExifAttribute) mAttributes[imageType].get(TAG_DEFAULT_CROP_SIZE);
3377        // RW2 image valid image size values
3378        ExifAttribute topBorderAttribute =
3379                (ExifAttribute) mAttributes[imageType].get(TAG_RW2_SENSOR_TOP_BORDER);
3380        ExifAttribute leftBorderAttribute =
3381                (ExifAttribute) mAttributes[imageType].get(TAG_RW2_SENSOR_LEFT_BORDER);
3382        ExifAttribute bottomBorderAttribute =
3383                (ExifAttribute) mAttributes[imageType].get(TAG_RW2_SENSOR_BOTTOM_BORDER);
3384        ExifAttribute rightBorderAttribute =
3385                (ExifAttribute) mAttributes[imageType].get(TAG_RW2_SENSOR_RIGHT_BORDER);
3386
3387        if (defaultCropSizeAttribute != null) {
3388            // Update for uncompressed image
3389            ExifAttribute defaultCropSizeXAttribute, defaultCropSizeYAttribute;
3390            if (defaultCropSizeAttribute.format == IFD_FORMAT_URATIONAL) {
3391                Rational[] defaultCropSizeValue =
3392                        (Rational[]) defaultCropSizeAttribute.getValue(mExifByteOrder);
3393                defaultCropSizeXAttribute =
3394                        ExifAttribute.createURational(defaultCropSizeValue[0], mExifByteOrder);
3395                defaultCropSizeYAttribute =
3396                        ExifAttribute.createURational(defaultCropSizeValue[1], mExifByteOrder);
3397            } else {
3398                int[] defaultCropSizeValue =
3399                        (int[]) defaultCropSizeAttribute.getValue(mExifByteOrder);
3400                defaultCropSizeXAttribute =
3401                        ExifAttribute.createUShort(defaultCropSizeValue[0], mExifByteOrder);
3402                defaultCropSizeYAttribute =
3403                        ExifAttribute.createUShort(defaultCropSizeValue[1], mExifByteOrder);
3404            }
3405            mAttributes[imageType].put(TAG_IMAGE_WIDTH, defaultCropSizeXAttribute);
3406            mAttributes[imageType].put(TAG_IMAGE_LENGTH, defaultCropSizeYAttribute);
3407        } else if (topBorderAttribute != null && leftBorderAttribute != null &&
3408                bottomBorderAttribute != null && rightBorderAttribute != null) {
3409            // Update for RW2 image
3410            int topBorderValue = topBorderAttribute.getIntValue(mExifByteOrder);
3411            int bottomBorderValue = bottomBorderAttribute.getIntValue(mExifByteOrder);
3412            int rightBorderValue = rightBorderAttribute.getIntValue(mExifByteOrder);
3413            int leftBorderValue = leftBorderAttribute.getIntValue(mExifByteOrder);
3414            if (bottomBorderValue > topBorderValue && rightBorderValue > leftBorderValue) {
3415                int length = bottomBorderValue - topBorderValue;
3416                int width = rightBorderValue - leftBorderValue;
3417                ExifAttribute imageLengthAttribute =
3418                        ExifAttribute.createUShort(length, mExifByteOrder);
3419                ExifAttribute imageWidthAttribute =
3420                        ExifAttribute.createUShort(width, mExifByteOrder);
3421                mAttributes[imageType].put(TAG_IMAGE_LENGTH, imageLengthAttribute);
3422                mAttributes[imageType].put(TAG_IMAGE_WIDTH, imageWidthAttribute);
3423            }
3424        } else {
3425            retrieveJpegImageSize(in, imageType);
3426        }
3427    }
3428
3429    // Writes an Exif segment into the given output stream.
3430    private int writeExifSegment(ByteOrderedDataOutputStream dataOutputStream,
3431            int exifOffsetFromBeginning) throws IOException {
3432        // The following variables are for calculating each IFD tag group size in bytes.
3433        int[] ifdOffsets = new int[EXIF_TAGS.length];
3434        int[] ifdDataSizes = new int[EXIF_TAGS.length];
3435
3436        // Remove IFD pointer tags (we'll re-add it later.)
3437        for (ExifTag tag : EXIF_POINTER_TAGS) {
3438            removeAttribute(tag.name);
3439        }
3440        // Remove old thumbnail data
3441        removeAttribute(JPEG_INTERCHANGE_FORMAT_TAG.name);
3442        removeAttribute(JPEG_INTERCHANGE_FORMAT_LENGTH_TAG.name);
3443
3444        // Remove null value tags.
3445        for (int ifdType = 0; ifdType < EXIF_TAGS.length; ++ifdType) {
3446            for (Object obj : mAttributes[ifdType].entrySet().toArray()) {
3447                final Map.Entry entry = (Map.Entry) obj;
3448                if (entry.getValue() == null) {
3449                    mAttributes[ifdType].remove(entry.getKey());
3450                }
3451            }
3452        }
3453
3454        // Add IFD pointer tags. The next offset of primary image TIFF IFD will have thumbnail IFD
3455        // offset when there is one or more tags in the thumbnail IFD.
3456        if (!mAttributes[IFD_TYPE_EXIF].isEmpty()) {
3457            mAttributes[IFD_TYPE_PRIMARY].put(EXIF_POINTER_TAGS[1].name,
3458                    ExifAttribute.createULong(0, mExifByteOrder));
3459        }
3460        if (!mAttributes[IFD_TYPE_GPS].isEmpty()) {
3461            mAttributes[IFD_TYPE_PRIMARY].put(EXIF_POINTER_TAGS[2].name,
3462                    ExifAttribute.createULong(0, mExifByteOrder));
3463        }
3464        if (!mAttributes[IFD_TYPE_INTEROPERABILITY].isEmpty()) {
3465            mAttributes[IFD_TYPE_EXIF].put(EXIF_POINTER_TAGS[3].name,
3466                    ExifAttribute.createULong(0, mExifByteOrder));
3467        }
3468        if (mHasThumbnail) {
3469            mAttributes[IFD_TYPE_THUMBNAIL].put(JPEG_INTERCHANGE_FORMAT_TAG.name,
3470                    ExifAttribute.createULong(0, mExifByteOrder));
3471            mAttributes[IFD_TYPE_THUMBNAIL].put(JPEG_INTERCHANGE_FORMAT_LENGTH_TAG.name,
3472                    ExifAttribute.createULong(mThumbnailLength, mExifByteOrder));
3473        }
3474
3475        // Calculate IFD group data area sizes. IFD group data area is assigned to save the entry
3476        // value which has a bigger size than 4 bytes.
3477        for (int i = 0; i < EXIF_TAGS.length; ++i) {
3478            int sum = 0;
3479            for (Map.Entry entry : (Set<Map.Entry>) mAttributes[i].entrySet()) {
3480                final ExifAttribute exifAttribute = (ExifAttribute) entry.getValue();
3481                final int size = exifAttribute.size();
3482                if (size > 4) {
3483                    sum += size;
3484                }
3485            }
3486            ifdDataSizes[i] += sum;
3487        }
3488
3489        // Calculate IFD offsets.
3490        int position = 8;
3491        for (int ifdType = 0; ifdType < EXIF_TAGS.length; ++ifdType) {
3492            if (!mAttributes[ifdType].isEmpty()) {
3493                ifdOffsets[ifdType] = position;
3494                position += 2 + mAttributes[ifdType].size() * 12 + 4 + ifdDataSizes[ifdType];
3495            }
3496        }
3497        if (mHasThumbnail) {
3498            int thumbnailOffset = position;
3499            mAttributes[IFD_TYPE_THUMBNAIL].put(JPEG_INTERCHANGE_FORMAT_TAG.name,
3500                    ExifAttribute.createULong(thumbnailOffset, mExifByteOrder));
3501            mThumbnailOffset = exifOffsetFromBeginning + thumbnailOffset;
3502            position += mThumbnailLength;
3503        }
3504
3505        // Calculate the total size
3506        int totalSize = position + 8;  // eight bytes is for header part.
3507        if (DEBUG) {
3508            Log.d(TAG, "totalSize length: " + totalSize);
3509            for (int i = 0; i < EXIF_TAGS.length; ++i) {
3510                Log.d(TAG, String.format("index: %d, offsets: %d, tag count: %d, data sizes: %d",
3511                        i, ifdOffsets[i], mAttributes[i].size(), ifdDataSizes[i]));
3512            }
3513        }
3514
3515        // Update IFD pointer tags with the calculated offsets.
3516        if (!mAttributes[IFD_TYPE_EXIF].isEmpty()) {
3517            mAttributes[IFD_TYPE_PRIMARY].put(EXIF_POINTER_TAGS[1].name,
3518                    ExifAttribute.createULong(ifdOffsets[IFD_TYPE_EXIF], mExifByteOrder));
3519        }
3520        if (!mAttributes[IFD_TYPE_GPS].isEmpty()) {
3521            mAttributes[IFD_TYPE_PRIMARY].put(EXIF_POINTER_TAGS[2].name,
3522                    ExifAttribute.createULong(ifdOffsets[IFD_TYPE_GPS], mExifByteOrder));
3523        }
3524        if (!mAttributes[IFD_TYPE_INTEROPERABILITY].isEmpty()) {
3525            mAttributes[IFD_TYPE_EXIF].put(EXIF_POINTER_TAGS[3].name, ExifAttribute.createULong(
3526                    ifdOffsets[IFD_TYPE_INTEROPERABILITY], mExifByteOrder));
3527        }
3528
3529        // Write TIFF Headers. See JEITA CP-3451C Section 4.5.2. Table 1.
3530        dataOutputStream.writeUnsignedShort(totalSize);
3531        dataOutputStream.write(IDENTIFIER_EXIF_APP1);
3532        dataOutputStream.writeShort(mExifByteOrder == ByteOrder.BIG_ENDIAN
3533                ? BYTE_ALIGN_MM : BYTE_ALIGN_II);
3534        dataOutputStream.setByteOrder(mExifByteOrder);
3535        dataOutputStream.writeUnsignedShort(START_CODE);
3536        dataOutputStream.writeUnsignedInt(IFD_OFFSET);
3537
3538        // Write IFD groups. See JEITA CP-3451C Section 4.5.8. Figure 9.
3539        for (int ifdType = 0; ifdType < EXIF_TAGS.length; ++ifdType) {
3540            if (!mAttributes[ifdType].isEmpty()) {
3541                // See JEITA CP-3451C Section 4.6.2: IFD structure.
3542                // Write entry count
3543                dataOutputStream.writeUnsignedShort(mAttributes[ifdType].size());
3544
3545                // Write entry info
3546                int dataOffset = ifdOffsets[ifdType] + 2 + mAttributes[ifdType].size() * 12 + 4;
3547                for (Map.Entry entry : (Set<Map.Entry>) mAttributes[ifdType].entrySet()) {
3548                    // Convert tag name to tag number.
3549                    final ExifTag tag =
3550                            (ExifTag) sExifTagMapsForWriting[ifdType].get(entry.getKey());
3551                    final int tagNumber = tag.number;
3552                    final ExifAttribute attribute = (ExifAttribute) entry.getValue();
3553                    final int size = attribute.size();
3554
3555                    dataOutputStream.writeUnsignedShort(tagNumber);
3556                    dataOutputStream.writeUnsignedShort(attribute.format);
3557                    dataOutputStream.writeInt(attribute.numberOfComponents);
3558                    if (size > 4) {
3559                        dataOutputStream.writeUnsignedInt(dataOffset);
3560                        dataOffset += size;
3561                    } else {
3562                        dataOutputStream.write(attribute.bytes);
3563                        // Fill zero up to 4 bytes
3564                        if (size < 4) {
3565                            for (int i = size; i < 4; ++i) {
3566                                dataOutputStream.writeByte(0);
3567                            }
3568                        }
3569                    }
3570                }
3571
3572                // Write the next offset. It writes the offset of thumbnail IFD if there is one or
3573                // more tags in the thumbnail IFD when the current IFD is the primary image TIFF
3574                // IFD; Otherwise 0.
3575                if (ifdType == 0 && !mAttributes[IFD_TYPE_THUMBNAIL].isEmpty()) {
3576                    dataOutputStream.writeUnsignedInt(ifdOffsets[IFD_TYPE_THUMBNAIL]);
3577                } else {
3578                    dataOutputStream.writeUnsignedInt(0);
3579                }
3580
3581                // Write values of data field exceeding 4 bytes after the next offset.
3582                for (Map.Entry entry : (Set<Map.Entry>) mAttributes[ifdType].entrySet()) {
3583                    ExifAttribute attribute = (ExifAttribute) entry.getValue();
3584
3585                    if (attribute.bytes.length > 4) {
3586                        dataOutputStream.write(attribute.bytes, 0, attribute.bytes.length);
3587                    }
3588                }
3589            }
3590        }
3591
3592        // Write thumbnail
3593        if (mHasThumbnail) {
3594            dataOutputStream.write(getThumbnailBytes());
3595        }
3596
3597        // Reset the byte order to big endian in order to write remaining parts of the JPEG file.
3598        dataOutputStream.setByteOrder(ByteOrder.BIG_ENDIAN);
3599
3600        return totalSize;
3601    }
3602
3603    /**
3604     * Determines the data format of EXIF entry value.
3605     *
3606     * @param entryValue The value to be determined.
3607     * @return Returns two data formats gussed as a pair in integer. If there is no two candidate
3608               data formats for the given entry value, returns {@code -1} in the second of the pair.
3609     */
3610    private static Pair<Integer, Integer> guessDataFormat(String entryValue) {
3611        // See TIFF 6.0 Section 2, "Image File Directory".
3612        // Take the first component if there are more than one component.
3613        if (entryValue.contains(",")) {
3614            String[] entryValues = entryValue.split(",");
3615            Pair<Integer, Integer> dataFormat = guessDataFormat(entryValues[0]);
3616            if (dataFormat.first == IFD_FORMAT_STRING) {
3617                return dataFormat;
3618            }
3619            for (int i = 1; i < entryValues.length; ++i) {
3620                final Pair<Integer, Integer> guessDataFormat = guessDataFormat(entryValues[i]);
3621                int first = -1, second = -1;
3622                if (guessDataFormat.first == dataFormat.first
3623                        || guessDataFormat.second == dataFormat.first) {
3624                    first = dataFormat.first;
3625                }
3626                if (dataFormat.second != -1 && (guessDataFormat.first == dataFormat.second
3627                        || guessDataFormat.second == dataFormat.second)) {
3628                    second = dataFormat.second;
3629                }
3630                if (first == -1 && second == -1) {
3631                    return new Pair<>(IFD_FORMAT_STRING, -1);
3632                }
3633                if (first == -1) {
3634                    dataFormat = new Pair<>(second, -1);
3635                    continue;
3636                }
3637                if (second == -1) {
3638                    dataFormat = new Pair<>(first, -1);
3639                    continue;
3640                }
3641            }
3642            return dataFormat;
3643        }
3644
3645        if (entryValue.contains("/")) {
3646            String[] rationalNumber = entryValue.split("/");
3647            if (rationalNumber.length == 2) {
3648                try {
3649                    long numerator = (long) Double.parseDouble(rationalNumber[0]);
3650                    long denominator = (long) Double.parseDouble(rationalNumber[1]);
3651                    if (numerator < 0L || denominator < 0L) {
3652                        return new Pair<>(IFD_FORMAT_SRATIONAL, -1);
3653                    }
3654                    if (numerator > Integer.MAX_VALUE || denominator > Integer.MAX_VALUE) {
3655                        return new Pair<>(IFD_FORMAT_URATIONAL, -1);
3656                    }
3657                    return new Pair<>(IFD_FORMAT_SRATIONAL, IFD_FORMAT_URATIONAL);
3658                } catch (NumberFormatException e)  {
3659                    // Ignored
3660                }
3661            }
3662            return new Pair<>(IFD_FORMAT_STRING, -1);
3663        }
3664        try {
3665            Long longValue = Long.parseLong(entryValue);
3666            if (longValue >= 0 && longValue <= 65535) {
3667                return new Pair<>(IFD_FORMAT_USHORT, IFD_FORMAT_ULONG);
3668            }
3669            if (longValue < 0) {
3670                return new Pair<>(IFD_FORMAT_SLONG, -1);
3671            }
3672            return new Pair<>(IFD_FORMAT_ULONG, -1);
3673        } catch (NumberFormatException e) {
3674            // Ignored
3675        }
3676        try {
3677            Double.parseDouble(entryValue);
3678            return new Pair<>(IFD_FORMAT_DOUBLE, -1);
3679        } catch (NumberFormatException e) {
3680            // Ignored
3681        }
3682        return new Pair<>(IFD_FORMAT_STRING, -1);
3683    }
3684
3685    // An input stream to parse EXIF data area, which can be written in either little or big endian
3686    // order.
3687    private static class ByteOrderedDataInputStream extends InputStream implements DataInput {
3688        private static final ByteOrder LITTLE_ENDIAN = ByteOrder.LITTLE_ENDIAN;
3689        private static final ByteOrder BIG_ENDIAN = ByteOrder.BIG_ENDIAN;
3690
3691        private DataInputStream mDataInputStream;
3692        private InputStream mInputStream;
3693        private ByteOrder mByteOrder = ByteOrder.BIG_ENDIAN;
3694        private final int mLength;
3695        private int mPosition;
3696
3697        public ByteOrderedDataInputStream(InputStream in) throws IOException {
3698            mInputStream = in;
3699            mDataInputStream = new DataInputStream(in);
3700            mLength = mDataInputStream.available();
3701            mPosition = 0;
3702            mDataInputStream.mark(mLength);
3703        }
3704
3705        public ByteOrderedDataInputStream(byte[] bytes) throws IOException {
3706            this(new ByteArrayInputStream(bytes));
3707        }
3708
3709        public void setByteOrder(ByteOrder byteOrder) {
3710            mByteOrder = byteOrder;
3711        }
3712
3713        public void seek(long byteCount) throws IOException {
3714            if (mPosition > byteCount) {
3715                mPosition = 0;
3716                mDataInputStream.reset();
3717                mDataInputStream.mark(mLength);
3718            } else {
3719                byteCount -= mPosition;
3720            }
3721
3722            if (skipBytes((int) byteCount) != (int) byteCount) {
3723                throw new IOException("Couldn't seek up to the byteCount");
3724            }
3725        }
3726
3727        public int peek() {
3728            return mPosition;
3729        }
3730
3731        @Override
3732        public int available() throws IOException {
3733            return mDataInputStream.available();
3734        }
3735
3736        @Override
3737        public int read() throws IOException {
3738            ++mPosition;
3739            return mDataInputStream.read();
3740        }
3741
3742        @Override
3743        public int readUnsignedByte() throws IOException {
3744            ++mPosition;
3745            return mDataInputStream.readUnsignedByte();
3746        }
3747
3748        @Override
3749        public String readLine() throws IOException {
3750            Log.d(TAG, "Currently unsupported");
3751            return null;
3752        }
3753
3754        @Override
3755        public boolean readBoolean() throws IOException {
3756            ++mPosition;
3757            return mDataInputStream.readBoolean();
3758        }
3759
3760        @Override
3761        public char readChar() throws IOException {
3762            mPosition += 2;
3763            return mDataInputStream.readChar();
3764        }
3765
3766        @Override
3767        public String readUTF() throws IOException {
3768            mPosition += 2;
3769            return mDataInputStream.readUTF();
3770        }
3771
3772        @Override
3773        public void readFully(byte[] buffer, int offset, int length) throws IOException {
3774            mPosition += length;
3775            if (mPosition > mLength) {
3776                throw new EOFException();
3777            }
3778            if (mDataInputStream.read(buffer, offset, length) != length) {
3779                throw new IOException("Couldn't read up to the length of buffer");
3780            }
3781        }
3782
3783        @Override
3784        public void readFully(byte[] buffer) throws IOException {
3785            mPosition += buffer.length;
3786            if (mPosition > mLength) {
3787                throw new EOFException();
3788            }
3789            if (mDataInputStream.read(buffer, 0, buffer.length) != buffer.length) {
3790                throw new IOException("Couldn't read up to the length of buffer");
3791            }
3792        }
3793
3794        @Override
3795        public byte readByte() throws IOException {
3796            ++mPosition;
3797            if (mPosition > mLength) {
3798                throw new EOFException();
3799            }
3800            int ch = mDataInputStream.read();
3801            if (ch < 0) {
3802                throw new EOFException();
3803            }
3804            return (byte) ch;
3805        }
3806
3807        @Override
3808        public short readShort() throws IOException {
3809            mPosition += 2;
3810            if (mPosition > mLength) {
3811                throw new EOFException();
3812            }
3813            int ch1 = mDataInputStream.read();
3814            int ch2 = mDataInputStream.read();
3815            if ((ch1 | ch2) < 0) {
3816                throw new EOFException();
3817            }
3818            if (mByteOrder == LITTLE_ENDIAN) {
3819                return (short) ((ch2 << 8) + (ch1));
3820            } else if (mByteOrder == BIG_ENDIAN) {
3821                return (short) ((ch1 << 8) + (ch2));
3822            }
3823            throw new IOException("Invalid byte order: " + mByteOrder);
3824        }
3825
3826        @Override
3827        public int readInt() throws IOException {
3828            mPosition += 4;
3829            if (mPosition > mLength) {
3830                throw new EOFException();
3831            }
3832            int ch1 = mDataInputStream.read();
3833            int ch2 = mDataInputStream.read();
3834            int ch3 = mDataInputStream.read();
3835            int ch4 = mDataInputStream.read();
3836            if ((ch1 | ch2 | ch3 | ch4) < 0) {
3837                throw new EOFException();
3838            }
3839            if (mByteOrder == LITTLE_ENDIAN) {
3840                return ((ch4 << 24) + (ch3 << 16) + (ch2 << 8) + ch1);
3841            } else if (mByteOrder == BIG_ENDIAN) {
3842                return ((ch1 << 24) + (ch2 << 16) + (ch3 << 8) + ch4);
3843            }
3844            throw new IOException("Invalid byte order: " + mByteOrder);
3845        }
3846
3847        @Override
3848        public int skipBytes(int byteCount) throws IOException {
3849            int totalSkip = Math.min(byteCount, mLength - mPosition);
3850            int skipped = 0;
3851            while (skipped < totalSkip) {
3852                skipped += mDataInputStream.skipBytes(totalSkip - skipped);
3853            }
3854            mPosition += skipped;
3855            return skipped;
3856        }
3857
3858        public int readUnsignedShort() throws IOException {
3859            mPosition += 2;
3860            if (mPosition > mLength) {
3861                throw new EOFException();
3862            }
3863            int ch1 = mDataInputStream.read();
3864            int ch2 = mDataInputStream.read();
3865            if ((ch1 | ch2) < 0) {
3866                throw new EOFException();
3867            }
3868            if (mByteOrder == LITTLE_ENDIAN) {
3869                return ((ch2 << 8) + (ch1));
3870            } else if (mByteOrder == BIG_ENDIAN) {
3871                return ((ch1 << 8) + (ch2));
3872            }
3873            throw new IOException("Invalid byte order: " + mByteOrder);
3874        }
3875
3876        public long readUnsignedInt() throws IOException {
3877            return readInt() & 0xffffffffL;
3878        }
3879
3880        @Override
3881        public long readLong() throws IOException {
3882            mPosition += 8;
3883            if (mPosition > mLength) {
3884                throw new EOFException();
3885            }
3886            int ch1 = mDataInputStream.read();
3887            int ch2 = mDataInputStream.read();
3888            int ch3 = mDataInputStream.read();
3889            int ch4 = mDataInputStream.read();
3890            int ch5 = mDataInputStream.read();
3891            int ch6 = mDataInputStream.read();
3892            int ch7 = mDataInputStream.read();
3893            int ch8 = mDataInputStream.read();
3894            if ((ch1 | ch2 | ch3 | ch4 | ch5 | ch6 | ch7 | ch8) < 0) {
3895                throw new EOFException();
3896            }
3897            if (mByteOrder == LITTLE_ENDIAN) {
3898                return (((long) ch8 << 56) + ((long) ch7 << 48) + ((long) ch6 << 40)
3899                        + ((long) ch5 << 32) + ((long) ch4 << 24) + ((long) ch3 << 16)
3900                        + ((long) ch2 << 8) + (long) ch1);
3901            } else if (mByteOrder == BIG_ENDIAN) {
3902                return (((long) ch1 << 56) + ((long) ch2 << 48) + ((long) ch3 << 40)
3903                        + ((long) ch4 << 32) + ((long) ch5 << 24) + ((long) ch6 << 16)
3904                        + ((long) ch7 << 8) + (long) ch8);
3905            }
3906            throw new IOException("Invalid byte order: " + mByteOrder);
3907        }
3908
3909        @Override
3910        public float readFloat() throws IOException {
3911            return Float.intBitsToFloat(readInt());
3912        }
3913
3914        @Override
3915        public double readDouble() throws IOException {
3916            return Double.longBitsToDouble(readLong());
3917        }
3918    }
3919
3920    // An output stream to write EXIF data area, which can be written in either little or big endian
3921    // order.
3922    private static class ByteOrderedDataOutputStream extends FilterOutputStream {
3923        private final OutputStream mOutputStream;
3924        private ByteOrder mByteOrder;
3925
3926        public ByteOrderedDataOutputStream(OutputStream out, ByteOrder byteOrder) {
3927            super(out);
3928            mOutputStream = out;
3929            mByteOrder = byteOrder;
3930        }
3931
3932        public void setByteOrder(ByteOrder byteOrder) {
3933            mByteOrder = byteOrder;
3934        }
3935
3936        public void write(byte[] bytes) throws IOException {
3937            mOutputStream.write(bytes);
3938        }
3939
3940        public void write(byte[] bytes, int offset, int length) throws IOException {
3941            mOutputStream.write(bytes, offset, length);
3942        }
3943
3944        public void writeByte(int val) throws IOException {
3945            mOutputStream.write(val);
3946        }
3947
3948        public void writeShort(short val) throws IOException {
3949            if (mByteOrder == ByteOrder.LITTLE_ENDIAN) {
3950                mOutputStream.write((val >>> 0) & 0xFF);
3951                mOutputStream.write((val >>> 8) & 0xFF);
3952            } else if (mByteOrder == ByteOrder.BIG_ENDIAN) {
3953                mOutputStream.write((val >>> 8) & 0xFF);
3954                mOutputStream.write((val >>> 0) & 0xFF);
3955            }
3956        }
3957
3958        public void writeInt(int val) throws IOException {
3959            if (mByteOrder == ByteOrder.LITTLE_ENDIAN) {
3960                mOutputStream.write((val >>> 0) & 0xFF);
3961                mOutputStream.write((val >>> 8) & 0xFF);
3962                mOutputStream.write((val >>> 16) & 0xFF);
3963                mOutputStream.write((val >>> 24) & 0xFF);
3964            } else if (mByteOrder == ByteOrder.BIG_ENDIAN) {
3965                mOutputStream.write((val >>> 24) & 0xFF);
3966                mOutputStream.write((val >>> 16) & 0xFF);
3967                mOutputStream.write((val >>> 8) & 0xFF);
3968                mOutputStream.write((val >>> 0) & 0xFF);
3969            }
3970        }
3971
3972        public void writeUnsignedShort(int val) throws IOException {
3973            writeShort((short) val);
3974        }
3975
3976        public void writeUnsignedInt(long val) throws IOException {
3977            writeInt((int) val);
3978        }
3979    }
3980
3981    // Swaps image data based on image size
3982    private void swapBasedOnImageSize(@IfdType int firstIfdType, @IfdType int secondIfdType)
3983            throws IOException {
3984        if (mAttributes[firstIfdType].isEmpty() || mAttributes[secondIfdType].isEmpty()) {
3985            if (DEBUG) {
3986                Log.d(TAG, "Cannot perform swap since only one image data exists");
3987            }
3988            return;
3989        }
3990
3991        ExifAttribute firstImageLengthAttribute =
3992                (ExifAttribute) mAttributes[firstIfdType].get(TAG_IMAGE_LENGTH);
3993        ExifAttribute firstImageWidthAttribute =
3994                (ExifAttribute) mAttributes[firstIfdType].get(TAG_IMAGE_WIDTH);
3995        ExifAttribute secondImageLengthAttribute =
3996                (ExifAttribute) mAttributes[secondIfdType].get(TAG_IMAGE_LENGTH);
3997        ExifAttribute secondImageWidthAttribute =
3998                (ExifAttribute) mAttributes[secondIfdType].get(TAG_IMAGE_WIDTH);
3999
4000        if (firstImageLengthAttribute == null || firstImageWidthAttribute == null) {
4001            if (DEBUG) {
4002                Log.d(TAG, "First image does not contain valid size information");
4003            }
4004        } else if (secondImageLengthAttribute == null || secondImageWidthAttribute == null) {
4005            if (DEBUG) {
4006                Log.d(TAG, "Second image does not contain valid size information");
4007            }
4008        } else {
4009            int firstImageLengthValue = firstImageLengthAttribute.getIntValue(mExifByteOrder);
4010            int firstImageWidthValue = firstImageWidthAttribute.getIntValue(mExifByteOrder);
4011            int secondImageLengthValue = secondImageLengthAttribute.getIntValue(mExifByteOrder);
4012            int secondImageWidthValue = secondImageWidthAttribute.getIntValue(mExifByteOrder);
4013
4014            if (firstImageLengthValue < secondImageLengthValue &&
4015                    firstImageWidthValue < secondImageWidthValue) {
4016                HashMap tempMap = mAttributes[firstIfdType];
4017                mAttributes[firstIfdType] = mAttributes[secondIfdType];
4018                mAttributes[secondIfdType] = tempMap;
4019            }
4020        }
4021    }
4022
4023    // Checks if there is a match
4024    private boolean containsMatch(byte[] mainBytes, byte[] findBytes) {
4025        for (int i = 0; i < mainBytes.length - findBytes.length; i++) {
4026            for (int j = 0; j < findBytes.length; j++) {
4027                if (mainBytes[i + j] != findBytes[j]) {
4028                    break;
4029                }
4030                if (j == findBytes.length - 1) {
4031                    return true;
4032                }
4033            }
4034        }
4035        return false;
4036    }
4037
4038    /**
4039     * Convert given int[] to long[]. If long[] is given, just return it.
4040     * Return null for other types of input.
4041     */
4042    private static long[] convertToLongArray(Object inputObj) {
4043        if (inputObj instanceof int[]) {
4044            int[] input = (int[]) inputObj;
4045            long[] result = new long[input.length];
4046            for (int i = 0; i < input.length; i++) {
4047                result[i] = input[i];
4048            }
4049            return result;
4050        } else if (inputObj instanceof long[]) {
4051            return (long[]) inputObj;
4052        }
4053        return null;
4054    }
4055}
4056