1/*
2 * Copyright (C) 2016 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 com.android.dialer.callcomposer.camera.exif;
18
19import com.android.dialer.common.LogUtil;
20import java.io.IOException;
21import java.io.InputStream;
22
23/** This class reads the EXIF header of a JPEG file and stores it in {@link ExifData}. */
24class ExifReader {
25
26  private final ExifInterface mInterface;
27
28  ExifReader(ExifInterface iRef) {
29    mInterface = iRef;
30  }
31
32  /**
33   * Parses the inputStream and and returns the EXIF data in an {@link ExifData}.
34   *
35   * @throws ExifInvalidFormatException
36   * @throws java.io.IOException
37   */
38  protected ExifData read(InputStream inputStream) throws ExifInvalidFormatException, IOException {
39    ExifParser parser = ExifParser.parse(inputStream, mInterface);
40    ExifData exifData = new ExifData();
41    ExifTag tag;
42
43    int event = parser.next();
44    while (event != ExifParser.EVENT_END) {
45      switch (event) {
46        case ExifParser.EVENT_START_OF_IFD:
47          exifData.addIfdData(new IfdData(parser.getCurrentIfd()));
48          break;
49        case ExifParser.EVENT_NEW_TAG:
50          tag = parser.getTag();
51          if (!tag.hasValue()) {
52            parser.registerForTagValue(tag);
53          } else {
54            exifData.getIfdData(tag.getIfd()).setTag(tag);
55          }
56          break;
57        case ExifParser.EVENT_VALUE_OF_REGISTERED_TAG:
58          tag = parser.getTag();
59          if (tag.getDataType() == ExifTag.TYPE_UNDEFINED) {
60            parser.readFullTagValue(tag);
61          }
62          exifData.getIfdData(tag.getIfd()).setTag(tag);
63          break;
64        case ExifParser.EVENT_COMPRESSED_IMAGE:
65          byte[] buf = new byte[parser.getCompressedImageSize()];
66          if (buf.length != parser.read(buf)) {
67            LogUtil.i("ExifReader.read", "Failed to read the compressed thumbnail");
68          }
69          break;
70        case ExifParser.EVENT_UNCOMPRESSED_STRIP:
71          buf = new byte[parser.getStripSize()];
72          if (buf.length != parser.read(buf)) {
73            LogUtil.i("ExifReader.read", "Failed to read the strip bytes");
74          }
75          break;
76      }
77      event = parser.next();
78    }
79    return exifData;
80  }
81}
82