1/*
2 * Copyright (C) 2006 Apple Computer, Inc.
3 *
4 * Portions are Copyright (C) 2001-6 mozilla.org
5 *
6 * Other contributors:
7 *   Stuart Parmenter <stuart@mozilla.com>
8 *
9 * Copyright (C) 2007-2009 Torch Mobile, Inc.
10 *
11 * This library is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU Lesser General Public
13 * License as published by the Free Software Foundation; either
14 * version 2.1 of the License, or (at your option) any later version.
15 *
16 * This library is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
19 * Lesser General Public License for more details.
20 *
21 * You should have received a copy of the GNU Lesser General Public
22 * License along with this library; if not, write to the Free Software
23 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
24 *
25 * Alternatively, the contents of this file may be used under the terms
26 * of either the Mozilla Public License Version 1.1, found at
27 * http://www.mozilla.org/MPL/ (the "MPL") or the GNU General Public
28 * License Version 2.0, found at http://www.fsf.org/copyleft/gpl.html
29 * (the "GPL"), in which case the provisions of the MPL or the GPL are
30 * applicable instead of those above.  If you wish to allow use of your
31 * version of this file only under the terms of one of those two
32 * licenses (the MPL or the GPL) and not to allow others to use your
33 * version of this file under the LGPL, indicate your decision by
34 * deletingthe provisions above and replace them with the notice and
35 * other provisions required by the MPL or the GPL, as the case may be.
36 * If you do not delete the provisions above, a recipient may use your
37 * version of this file under any of the LGPL, the MPL or the GPL.
38 */
39
40#include "config.h"
41#include "platform/image-decoders/jpeg/JPEGImageDecoder.h"
42
43#include "platform/PlatformInstrumentation.h"
44#include "wtf/PassOwnPtr.h"
45#include "wtf/dtoa/utils.h"
46
47extern "C" {
48#include <stdio.h> // jpeglib.h needs stdio FILE.
49#include "jpeglib.h"
50#if USE(ICCJPEG)
51#include "iccjpeg.h"
52#endif
53#if USE(QCMSLIB)
54#include "qcms.h"
55#endif
56#include <setjmp.h>
57}
58
59#if CPU(BIG_ENDIAN) || CPU(MIDDLE_ENDIAN)
60#error Blink assumes a little-endian target.
61#endif
62
63#if defined(JCS_ALPHA_EXTENSIONS)
64#define TURBO_JPEG_RGB_SWIZZLE
65#if SK_B32_SHIFT // Output little-endian RGBA pixels (Android).
66inline J_COLOR_SPACE rgbOutputColorSpace() { return JCS_EXT_RGBA; }
67#else // Output little-endian BGRA pixels.
68inline J_COLOR_SPACE rgbOutputColorSpace() { return JCS_EXT_BGRA; }
69#endif
70inline bool turboSwizzled(J_COLOR_SPACE colorSpace) { return colorSpace == JCS_EXT_RGBA || colorSpace == JCS_EXT_BGRA; }
71inline bool colorSpaceHasAlpha(J_COLOR_SPACE colorSpace) { return turboSwizzled(colorSpace); }
72#else
73inline J_COLOR_SPACE rgbOutputColorSpace() { return JCS_RGB; }
74inline bool colorSpaceHasAlpha(J_COLOR_SPACE) { return false; }
75#endif
76
77#if USE(LOW_QUALITY_IMAGE_NO_JPEG_DITHERING)
78inline J_DCT_METHOD dctMethod() { return JDCT_IFAST; }
79inline J_DITHER_MODE ditherMode() { return JDITHER_NONE; }
80#else
81inline J_DCT_METHOD dctMethod() { return JDCT_ISLOW; }
82inline J_DITHER_MODE ditherMode() { return JDITHER_FS; }
83#endif
84
85#if USE(LOW_QUALITY_IMAGE_NO_JPEG_FANCY_UPSAMPLING)
86inline bool doFancyUpsampling() { return false; }
87#else
88inline bool doFancyUpsampling() { return true; }
89#endif
90
91namespace {
92
93const int exifMarker = JPEG_APP0 + 1;
94
95// JPEG only supports a denominator of 8.
96const unsigned scaleDenominator = 8;
97
98} // namespace
99
100namespace blink {
101
102struct decoder_error_mgr {
103    struct jpeg_error_mgr pub; // "public" fields for IJG library
104    jmp_buf setjmp_buffer;     // For handling catastropic errors
105};
106
107enum jstate {
108    JPEG_HEADER,                 // Reading JFIF headers
109    JPEG_START_DECOMPRESS,
110    JPEG_DECOMPRESS_PROGRESSIVE, // Output progressive pixels
111    JPEG_DECOMPRESS_SEQUENTIAL,  // Output sequential pixels
112    JPEG_DONE,
113    JPEG_ERROR
114};
115
116enum yuv_subsampling {
117    YUV_UNKNOWN,
118    YUV_410,
119    YUV_411,
120    YUV_420,
121    YUV_422,
122    YUV_440,
123    YUV_444
124};
125
126void init_source(j_decompress_ptr jd);
127boolean fill_input_buffer(j_decompress_ptr jd);
128void skip_input_data(j_decompress_ptr jd, long num_bytes);
129void term_source(j_decompress_ptr jd);
130void error_exit(j_common_ptr cinfo);
131
132// Implementation of a JPEG src object that understands our state machine
133struct decoder_source_mgr {
134    // public fields; must be first in this struct!
135    struct jpeg_source_mgr pub;
136
137    JPEGImageReader* decoder;
138};
139
140static unsigned readUint16(JOCTET* data, bool isBigEndian)
141{
142    if (isBigEndian)
143        return (GETJOCTET(data[0]) << 8) | GETJOCTET(data[1]);
144    return (GETJOCTET(data[1]) << 8) | GETJOCTET(data[0]);
145}
146
147static unsigned readUint32(JOCTET* data, bool isBigEndian)
148{
149    if (isBigEndian)
150        return (GETJOCTET(data[0]) << 24) | (GETJOCTET(data[1]) << 16) | (GETJOCTET(data[2]) << 8) | GETJOCTET(data[3]);
151    return (GETJOCTET(data[3]) << 24) | (GETJOCTET(data[2]) << 16) | (GETJOCTET(data[1]) << 8) | GETJOCTET(data[0]);
152}
153
154static bool checkExifHeader(jpeg_saved_marker_ptr marker, bool& isBigEndian, unsigned& ifdOffset)
155{
156    // For exif data, the APP1 block is followed by 'E', 'x', 'i', 'f', '\0',
157    // then a fill byte, and then a tiff file that contains the metadata.
158    // A tiff file starts with 'I', 'I' (intel / little endian byte order) or
159    // 'M', 'M' (motorola / big endian byte order), followed by (uint16_t)42,
160    // followed by an uint32_t with the offset to the tag block, relative to the
161    // tiff file start.
162    const unsigned exifHeaderSize = 14;
163    if (!(marker->marker == exifMarker
164        && marker->data_length >= exifHeaderSize
165        && marker->data[0] == 'E'
166        && marker->data[1] == 'x'
167        && marker->data[2] == 'i'
168        && marker->data[3] == 'f'
169        && marker->data[4] == '\0'
170        // data[5] is a fill byte
171        && ((marker->data[6] == 'I' && marker->data[7] == 'I')
172            || (marker->data[6] == 'M' && marker->data[7] == 'M'))))
173        return false;
174
175    isBigEndian = marker->data[6] == 'M';
176    if (readUint16(marker->data + 8, isBigEndian) != 42)
177        return false;
178
179    ifdOffset = readUint32(marker->data + 10, isBigEndian);
180    return true;
181}
182
183static ImageOrientation readImageOrientation(jpeg_decompress_struct* info)
184{
185    // The JPEG decoder looks at EXIF metadata.
186    // FIXME: Possibly implement XMP and IPTC support.
187    const unsigned orientationTag = 0x112;
188    const unsigned shortType = 3;
189    for (jpeg_saved_marker_ptr marker = info->marker_list; marker; marker = marker->next) {
190        bool isBigEndian;
191        unsigned ifdOffset;
192        if (!checkExifHeader(marker, isBigEndian, ifdOffset))
193            continue;
194        const unsigned offsetToTiffData = 6; // Account for 'Exif\0<fill byte>' header.
195        if (marker->data_length < offsetToTiffData || ifdOffset >= marker->data_length - offsetToTiffData)
196            continue;
197        ifdOffset += offsetToTiffData;
198
199        // The jpeg exif container format contains a tiff block for metadata.
200        // A tiff image file directory (ifd) consists of a uint16_t describing
201        // the number of ifd entries, followed by that many entries.
202        // When touching this code, it's useful to look at the tiff spec:
203        // http://partners.adobe.com/public/developer/en/tiff/TIFF6.pdf
204        JOCTET* ifd = marker->data + ifdOffset;
205        JOCTET* end = marker->data + marker->data_length;
206        if (end - ifd < 2)
207            continue;
208        unsigned tagCount = readUint16(ifd, isBigEndian);
209        ifd += 2; // Skip over the uint16 that was just read.
210
211        // Every ifd entry is 2 bytes of tag, 2 bytes of contents datatype,
212        // 4 bytes of number-of-elements, and 4 bytes of either offset to the
213        // tag data, or if the data is small enough, the inlined data itself.
214        const int ifdEntrySize = 12;
215        for (unsigned i = 0; i < tagCount && end - ifd >= ifdEntrySize; ++i, ifd += ifdEntrySize) {
216            unsigned tag = readUint16(ifd, isBigEndian);
217            unsigned type = readUint16(ifd + 2, isBigEndian);
218            unsigned count = readUint32(ifd + 4, isBigEndian);
219            if (tag == orientationTag && type == shortType && count == 1)
220                return ImageOrientation::fromEXIFValue(readUint16(ifd + 8, isBigEndian));
221        }
222    }
223
224    return ImageOrientation();
225}
226
227#if USE(QCMSLIB)
228static void readColorProfile(jpeg_decompress_struct* info, ColorProfile& colorProfile)
229{
230#if USE(ICCJPEG)
231    JOCTET* profile;
232    unsigned profileLength;
233
234    if (!read_icc_profile(info, &profile, &profileLength))
235        return;
236
237    // Only accept RGB color profiles from input class devices.
238    bool ignoreProfile = false;
239    char* profileData = reinterpret_cast<char*>(profile);
240    if (profileLength < ImageDecoder::iccColorProfileHeaderLength)
241        ignoreProfile = true;
242    else if (!ImageDecoder::rgbColorProfile(profileData, profileLength))
243        ignoreProfile = true;
244    else if (!ImageDecoder::inputDeviceColorProfile(profileData, profileLength))
245        ignoreProfile = true;
246
247    ASSERT(colorProfile.isEmpty());
248    if (!ignoreProfile)
249        colorProfile.append(profileData, profileLength);
250    free(profile);
251#endif
252}
253#endif
254
255static IntSize computeYUVSize(const jpeg_decompress_struct* info, int component, ImageDecoder::SizeType sizeType)
256{
257    if (sizeType == ImageDecoder::SizeForMemoryAllocation) {
258        return IntSize(info->cur_comp_info[component]->width_in_blocks * DCTSIZE, info->cur_comp_info[component]->height_in_blocks * DCTSIZE);
259    }
260    return IntSize(info->cur_comp_info[component]->downsampled_width, info->cur_comp_info[component]->downsampled_height);
261}
262
263static yuv_subsampling yuvSubsampling(const jpeg_decompress_struct& info)
264{
265    if ((DCTSIZE == 8)
266        && (info.num_components == 3)
267        && (info.comps_in_scan >= info.num_components)
268        && (info.scale_denom <= 8)
269        && (info.cur_comp_info[0])
270        && (info.cur_comp_info[1])
271        && (info.cur_comp_info[2])
272        && (info.cur_comp_info[1]->h_samp_factor == 1)
273        && (info.cur_comp_info[1]->v_samp_factor == 1)
274        && (info.cur_comp_info[2]->h_samp_factor == 1)
275        && (info.cur_comp_info[2]->v_samp_factor == 1)) {
276        int h = info.cur_comp_info[0]->h_samp_factor;
277        int v = info.cur_comp_info[0]->v_samp_factor;
278        // 4:4:4 : (h == 1) && (v == 1)
279        // 4:4:0 : (h == 1) && (v == 2)
280        // 4:2:2 : (h == 2) && (v == 1)
281        // 4:2:0 : (h == 2) && (v == 2)
282        // 4:1:1 : (h == 4) && (v == 1)
283        // 4:1:0 : (h == 4) && (v == 2)
284        if (v == 1) {
285            switch (h) {
286            case 1:
287                return YUV_444;
288            case 2:
289                return YUV_422;
290            case 4:
291                return YUV_411;
292            default:
293                break;
294            }
295        } else if (v == 2) {
296            switch (h) {
297            case 1:
298                return YUV_440;
299            case 2:
300                return YUV_420;
301            case 4:
302                return YUV_410;
303            default:
304                break;
305            }
306        }
307    }
308
309    return YUV_UNKNOWN;
310}
311
312class JPEGImageReader {
313    WTF_MAKE_FAST_ALLOCATED;
314public:
315    JPEGImageReader(JPEGImageDecoder* decoder)
316        : m_decoder(decoder)
317        , m_bufferLength(0)
318        , m_bytesToSkip(0)
319        , m_state(JPEG_HEADER)
320        , m_samples(0)
321#if USE(QCMSLIB)
322        , m_transform(0)
323#endif
324    {
325        memset(&m_info, 0, sizeof(jpeg_decompress_struct));
326
327        // We set up the normal JPEG error routines, then override error_exit.
328        m_info.err = jpeg_std_error(&m_err.pub);
329        m_err.pub.error_exit = error_exit;
330
331        // Allocate and initialize JPEG decompression object.
332        jpeg_create_decompress(&m_info);
333
334        decoder_source_mgr* src = 0;
335        if (!m_info.src) {
336            src = (decoder_source_mgr*)fastZeroedMalloc(sizeof(decoder_source_mgr));
337            if (!src) {
338                m_state = JPEG_ERROR;
339                return;
340            }
341        }
342
343        m_info.src = (jpeg_source_mgr*)src;
344
345        // Set up callback functions.
346        src->pub.init_source = init_source;
347        src->pub.fill_input_buffer = fill_input_buffer;
348        src->pub.skip_input_data = skip_input_data;
349        src->pub.resync_to_restart = jpeg_resync_to_restart;
350        src->pub.term_source = term_source;
351        src->decoder = this;
352
353#if USE(ICCJPEG)
354        // Retain ICC color profile markers for color management.
355        setup_read_icc_profile(&m_info);
356#endif
357
358        // Keep APP1 blocks, for obtaining exif data.
359        jpeg_save_markers(&m_info, exifMarker, 0xFFFF);
360    }
361
362    ~JPEGImageReader()
363    {
364        close();
365    }
366
367    void close()
368    {
369        decoder_source_mgr* src = (decoder_source_mgr*)m_info.src;
370        if (src)
371            fastFree(src);
372        m_info.src = 0;
373
374#if USE(QCMSLIB)
375        clearColorTransform();
376#endif
377        jpeg_destroy_decompress(&m_info);
378    }
379
380    void skipBytes(long numBytes)
381    {
382        decoder_source_mgr* src = (decoder_source_mgr*)m_info.src;
383        long bytesToSkip = std::min(numBytes, (long)src->pub.bytes_in_buffer);
384        src->pub.bytes_in_buffer -= (size_t)bytesToSkip;
385        src->pub.next_input_byte += bytesToSkip;
386
387        m_bytesToSkip = std::max(numBytes - bytesToSkip, static_cast<long>(0));
388    }
389
390    bool decode(const SharedBuffer& data, bool onlySize)
391    {
392        unsigned newByteCount = data.size() - m_bufferLength;
393        unsigned readOffset = m_bufferLength - m_info.src->bytes_in_buffer;
394
395        m_info.src->bytes_in_buffer += newByteCount;
396        m_info.src->next_input_byte = (JOCTET*)(data.data()) + readOffset;
397
398        // If we still have bytes to skip, try to skip those now.
399        if (m_bytesToSkip)
400            skipBytes(m_bytesToSkip);
401
402        m_bufferLength = data.size();
403
404        // We need to do the setjmp here. Otherwise bad things will happen
405        if (setjmp(m_err.setjmp_buffer))
406            return m_decoder->setFailed();
407
408        J_COLOR_SPACE overrideColorSpace = JCS_UNKNOWN;
409        switch (m_state) {
410        case JPEG_HEADER:
411            // Read file parameters with jpeg_read_header().
412            if (jpeg_read_header(&m_info, true) == JPEG_SUSPENDED)
413                return false; // I/O suspension.
414
415            switch (m_info.jpeg_color_space) {
416            case JCS_YCbCr:
417                // libjpeg can convert YCbCr image pixels to RGB.
418                m_info.out_color_space = rgbOutputColorSpace();
419                if (m_decoder->hasImagePlanes() && (yuvSubsampling(m_info) != YUV_UNKNOWN))
420                    overrideColorSpace = JCS_YCbCr;
421                break;
422            case JCS_GRAYSCALE:
423            case JCS_RGB:
424                // libjpeg can convert GRAYSCALE image pixels to RGB.
425                m_info.out_color_space = rgbOutputColorSpace();
426#if defined(TURBO_JPEG_RGB_SWIZZLE)
427                if (m_info.saw_JFIF_marker)
428                    break;
429                // FIXME: Swizzle decoding does not support Adobe transform=0
430                // images (yet), so revert to using JSC_RGB in that case.
431                if (m_info.saw_Adobe_marker && !m_info.Adobe_transform)
432                    m_info.out_color_space = JCS_RGB;
433#endif
434                break;
435            case JCS_CMYK:
436            case JCS_YCCK:
437                // libjpeg can convert YCCK to CMYK, but neither to RGB, so we
438                // manually convert CMKY to RGB.
439                m_info.out_color_space = JCS_CMYK;
440                break;
441            default:
442                return m_decoder->setFailed();
443            }
444
445            m_state = JPEG_START_DECOMPRESS;
446
447            // We can fill in the size now that the header is available.
448            if (!m_decoder->setSize(m_info.image_width, m_info.image_height))
449                return false;
450
451            // Calculate and set decoded size.
452            m_info.scale_num = m_decoder->desiredScaleNumerator();
453            m_info.scale_denom = scaleDenominator;
454            jpeg_calc_output_dimensions(&m_info);
455            m_decoder->setDecodedSize(m_info.output_width, m_info.output_height);
456
457            m_decoder->setOrientation(readImageOrientation(info()));
458
459#if USE(QCMSLIB)
460            // Allow color management of the decoded RGBA pixels if possible.
461            if (!m_decoder->ignoresGammaAndColorProfile()) {
462                ColorProfile colorProfile;
463                readColorProfile(info(), colorProfile);
464                createColorTransform(colorProfile, colorSpaceHasAlpha(m_info.out_color_space));
465                if (m_transform) {
466                    overrideColorSpace = JCS_UNKNOWN;
467#if defined(TURBO_JPEG_RGB_SWIZZLE)
468                    // Input RGBA data to qcms. Note: restored to BGRA on output.
469                    if (m_info.out_color_space == JCS_EXT_BGRA)
470                        m_info.out_color_space = JCS_EXT_RGBA;
471#endif
472                }
473                m_decoder->setHasColorProfile(!!m_transform);
474            }
475#endif
476            if (overrideColorSpace == JCS_YCbCr) {
477                m_info.out_color_space = JCS_YCbCr;
478                m_info.raw_data_out = TRUE;
479                m_uvSize = computeYUVSize(&m_info, 1, ImageDecoder::SizeForMemoryAllocation); // U size and V size have to be the same if we got here
480            }
481
482            // Don't allocate a giant and superfluous memory buffer when the
483            // image is a sequential JPEG.
484            m_info.buffered_image = jpeg_has_multiple_scans(&m_info);
485
486            if (onlySize) {
487                // We can stop here. Reduce our buffer length and available data.
488                m_bufferLength -= m_info.src->bytes_in_buffer;
489                m_info.src->bytes_in_buffer = 0;
490                return true;
491            }
492        // FALL THROUGH
493
494        case JPEG_START_DECOMPRESS:
495            // Set parameters for decompression.
496            // FIXME -- Should reset dct_method and dither mode for final pass
497            // of progressive JPEG.
498            m_info.dct_method = dctMethod();
499            m_info.dither_mode = ditherMode();
500            m_info.do_fancy_upsampling = doFancyUpsampling();
501            m_info.enable_2pass_quant = false;
502            m_info.do_block_smoothing = true;
503
504            // Make a one-row-high sample array that will go away when done with
505            // image. Always make it big enough to hold an RGB row. Since this
506            // uses the IJG memory manager, it must be allocated before the call
507            // to jpeg_start_compress().
508            // FIXME: note that some output color spaces do not need the samples
509            // buffer. Remove this allocation for those color spaces.
510            m_samples = (*m_info.mem->alloc_sarray)(reinterpret_cast<j_common_ptr>(&m_info), JPOOL_IMAGE, m_info.output_width * 4, m_info.out_color_space == JCS_YCbCr ? 2 : 1);
511
512            // Start decompressor.
513            if (!jpeg_start_decompress(&m_info))
514                return false; // I/O suspension.
515
516            // If this is a progressive JPEG ...
517            m_state = (m_info.buffered_image) ? JPEG_DECOMPRESS_PROGRESSIVE : JPEG_DECOMPRESS_SEQUENTIAL;
518        // FALL THROUGH
519
520        case JPEG_DECOMPRESS_SEQUENTIAL:
521            if (m_state == JPEG_DECOMPRESS_SEQUENTIAL) {
522
523                if (!m_decoder->outputScanlines())
524                    return false; // I/O suspension.
525
526                // If we've completed image output...
527                ASSERT(m_info.output_scanline == m_info.output_height);
528                m_state = JPEG_DONE;
529            }
530        // FALL THROUGH
531
532        case JPEG_DECOMPRESS_PROGRESSIVE:
533            if (m_state == JPEG_DECOMPRESS_PROGRESSIVE) {
534                int status;
535                do {
536                    status = jpeg_consume_input(&m_info);
537                } while ((status != JPEG_SUSPENDED) && (status != JPEG_REACHED_EOI));
538
539                for (;;) {
540                    if (!m_info.output_scanline) {
541                        int scan = m_info.input_scan_number;
542
543                        // If we haven't displayed anything yet
544                        // (output_scan_number == 0) and we have enough data for
545                        // a complete scan, force output of the last full scan.
546                        if (!m_info.output_scan_number && (scan > 1) && (status != JPEG_REACHED_EOI))
547                            --scan;
548
549                        if (!jpeg_start_output(&m_info, scan))
550                            return false; // I/O suspension.
551                    }
552
553                    if (m_info.output_scanline == 0xffffff)
554                        m_info.output_scanline = 0;
555
556                    // If outputScanlines() fails, it deletes |this|. Therefore,
557                    // copy the decoder pointer and use it to check for failure
558                    // to avoid member access in the failure case.
559                    JPEGImageDecoder* decoder = m_decoder;
560                    if (!decoder->outputScanlines()) {
561                        if (decoder->failed()) // Careful; |this| is deleted.
562                            return false;
563                        if (!m_info.output_scanline)
564                            // Didn't manage to read any lines - flag so we
565                            // don't call jpeg_start_output() multiple times for
566                            // the same scan.
567                            m_info.output_scanline = 0xffffff;
568                        return false; // I/O suspension.
569                    }
570
571                    if (m_info.output_scanline == m_info.output_height) {
572                        if (!jpeg_finish_output(&m_info))
573                            return false; // I/O suspension.
574
575                        if (jpeg_input_complete(&m_info) && (m_info.input_scan_number == m_info.output_scan_number))
576                            break;
577
578                        m_info.output_scanline = 0;
579                    }
580                }
581
582                m_state = JPEG_DONE;
583            }
584        // FALL THROUGH
585
586        case JPEG_DONE:
587            // Finish decompression.
588            return jpeg_finish_decompress(&m_info);
589
590        case JPEG_ERROR:
591            // We can get here if the constructor failed.
592            return m_decoder->setFailed();
593        }
594
595        return true;
596    }
597
598    jpeg_decompress_struct* info() { return &m_info; }
599    JSAMPARRAY samples() const { return m_samples; }
600    JPEGImageDecoder* decoder() { return m_decoder; }
601    IntSize uvSize() const { return m_uvSize; }
602#if USE(QCMSLIB)
603    qcms_transform* colorTransform() const { return m_transform; }
604
605    void clearColorTransform()
606    {
607        if (m_transform)
608            qcms_transform_release(m_transform);
609        m_transform = 0;
610    }
611
612    void createColorTransform(const ColorProfile& colorProfile, bool hasAlpha)
613    {
614        clearColorTransform();
615
616        if (colorProfile.isEmpty())
617            return;
618        qcms_profile* deviceProfile = ImageDecoder::qcmsOutputDeviceProfile();
619        if (!deviceProfile)
620            return;
621        qcms_profile* inputProfile = qcms_profile_from_memory(colorProfile.data(), colorProfile.size());
622        if (!inputProfile)
623            return;
624        // We currently only support color profiles for RGB profiled images.
625        ASSERT(icSigRgbData == qcms_profile_get_color_space(inputProfile));
626        qcms_data_type dataFormat = hasAlpha ? QCMS_DATA_RGBA_8 : QCMS_DATA_RGB_8;
627        // FIXME: Don't force perceptual intent if the image profile contains an intent.
628        m_transform = qcms_transform_create(inputProfile, dataFormat, deviceProfile, dataFormat, QCMS_INTENT_PERCEPTUAL);
629        qcms_profile_release(inputProfile);
630    }
631#endif
632
633private:
634    JPEGImageDecoder* m_decoder;
635    unsigned m_bufferLength;
636    int m_bytesToSkip;
637
638    jpeg_decompress_struct m_info;
639    decoder_error_mgr m_err;
640    jstate m_state;
641
642    JSAMPARRAY m_samples;
643
644    IntSize m_uvSize;
645
646#if USE(QCMSLIB)
647    qcms_transform* m_transform;
648#endif
649};
650
651// Override the standard error method in the IJG JPEG decoder code.
652void error_exit(j_common_ptr cinfo)
653{
654    // Return control to the setjmp point.
655    decoder_error_mgr *err = reinterpret_cast_ptr<decoder_error_mgr *>(cinfo->err);
656    longjmp(err->setjmp_buffer, -1);
657}
658
659void init_source(j_decompress_ptr)
660{
661}
662
663void skip_input_data(j_decompress_ptr jd, long num_bytes)
664{
665    decoder_source_mgr *src = (decoder_source_mgr *)jd->src;
666    src->decoder->skipBytes(num_bytes);
667}
668
669boolean fill_input_buffer(j_decompress_ptr)
670{
671    // Our decode step always sets things up properly, so if this method is ever
672    // called, then we have hit the end of the buffer.  A return value of false
673    // indicates that we have no data to supply yet.
674    return false;
675}
676
677void term_source(j_decompress_ptr jd)
678{
679    decoder_source_mgr *src = (decoder_source_mgr *)jd->src;
680    src->decoder->decoder()->jpegComplete();
681}
682
683JPEGImageDecoder::JPEGImageDecoder(ImageSource::AlphaOption alphaOption,
684    ImageSource::GammaAndColorProfileOption gammaAndColorProfileOption,
685    size_t maxDecodedBytes)
686    : ImageDecoder(alphaOption, gammaAndColorProfileOption, maxDecodedBytes)
687    , m_hasColorProfile(false)
688{
689}
690
691JPEGImageDecoder::~JPEGImageDecoder()
692{
693}
694
695bool JPEGImageDecoder::isSizeAvailable()
696{
697    if (!ImageDecoder::isSizeAvailable())
698         decode(true);
699
700    return ImageDecoder::isSizeAvailable();
701}
702
703bool JPEGImageDecoder::setSize(unsigned width, unsigned height)
704{
705    if (!ImageDecoder::setSize(width, height))
706        return false;
707
708    if (!desiredScaleNumerator())
709        return setFailed();
710
711    setDecodedSize(width, height);
712    return true;
713}
714
715void JPEGImageDecoder::setDecodedSize(unsigned width, unsigned height)
716{
717    m_decodedSize = IntSize(width, height);
718}
719
720IntSize JPEGImageDecoder::decodedYUVSize(int component, ImageDecoder::SizeType sizeType) const
721{
722    ASSERT((component >= 0) && (component <= 2) && m_reader);
723    const jpeg_decompress_struct* info = m_reader->info();
724
725    ASSERT(info->out_color_space == JCS_YCbCr);
726    return computeYUVSize(info, component, sizeType);
727}
728
729unsigned JPEGImageDecoder::desiredScaleNumerator() const
730{
731    size_t originalBytes = size().width() * size().height() * 4;
732    if (originalBytes <= m_maxDecodedBytes) {
733        return scaleDenominator;
734    }
735
736    // Downsample according to the maximum decoded size.
737    unsigned scaleNumerator = static_cast<unsigned>(floor(sqrt(
738        // MSVC needs explicit parameter type for sqrt().
739        static_cast<float>(m_maxDecodedBytes * scaleDenominator * scaleDenominator / originalBytes))));
740
741    return scaleNumerator;
742}
743
744bool JPEGImageDecoder::canDecodeToYUV() const
745{
746    ASSERT(ImageDecoder::isSizeAvailable() && m_reader);
747
748    return m_reader->info()->out_color_space == JCS_YCbCr;
749}
750
751bool JPEGImageDecoder::decodeToYUV()
752{
753    if (!hasImagePlanes())
754        return false;
755    PlatformInstrumentation::willDecodeImage("JPEG");
756    decode(false);
757    PlatformInstrumentation::didDecodeImage();
758    return !failed();
759}
760
761ImageFrame* JPEGImageDecoder::frameBufferAtIndex(size_t index)
762{
763    if (index)
764        return 0;
765
766    if (m_frameBufferCache.isEmpty()) {
767        m_frameBufferCache.resize(1);
768        m_frameBufferCache[0].setPremultiplyAlpha(m_premultiplyAlpha);
769    }
770
771    ImageFrame& frame = m_frameBufferCache[0];
772    if (frame.status() != ImageFrame::FrameComplete) {
773        PlatformInstrumentation::willDecodeImage("JPEG");
774        decode(false);
775        PlatformInstrumentation::didDecodeImage();
776    }
777
778    frame.notifyBitmapIfPixelsChanged();
779    return &frame;
780}
781
782bool JPEGImageDecoder::setFailed()
783{
784    m_reader.clear();
785    return ImageDecoder::setFailed();
786}
787
788void JPEGImageDecoder::setImagePlanes(PassOwnPtr<ImagePlanes> imagePlanes)
789{
790    m_imagePlanes = imagePlanes;
791}
792
793template <J_COLOR_SPACE colorSpace> void setPixel(ImageFrame& buffer, ImageFrame::PixelData* pixel, JSAMPARRAY samples, int column)
794{
795    ASSERT_NOT_REACHED();
796}
797
798template <> void setPixel<JCS_RGB>(ImageFrame& buffer, ImageFrame::PixelData* pixel, JSAMPARRAY samples, int column)
799{
800    JSAMPLE* jsample = *samples + column * 3;
801    buffer.setRGBARaw(pixel, jsample[0], jsample[1], jsample[2], 255);
802}
803
804template <> void setPixel<JCS_CMYK>(ImageFrame& buffer, ImageFrame::PixelData* pixel, JSAMPARRAY samples, int column)
805{
806    JSAMPLE* jsample = *samples + column * 4;
807
808    // Source is 'Inverted CMYK', output is RGB.
809    // See: http://www.easyrgb.com/math.php?MATH=M12#text12
810    // Or: http://www.ilkeratalay.com/colorspacesfaq.php#rgb
811    // From CMYK to CMY:
812    // X =   X    * (1 -   K   ) +   K  [for X = C, M, or Y]
813    // Thus, from Inverted CMYK to CMY is:
814    // X = (1-iX) * (1 - (1-iK)) + (1-iK) => 1 - iX*iK
815    // From CMY (0..1) to RGB (0..1):
816    // R = 1 - C => 1 - (1 - iC*iK) => iC*iK  [G and B similar]
817    unsigned k = jsample[3];
818    buffer.setRGBARaw(pixel, jsample[0] * k / 255, jsample[1] * k / 255, jsample[2] * k / 255, 255);
819}
820
821template <J_COLOR_SPACE colorSpace> bool outputRows(JPEGImageReader* reader, ImageFrame& buffer)
822{
823    JSAMPARRAY samples = reader->samples();
824    jpeg_decompress_struct* info = reader->info();
825    int width = info->output_width;
826
827    while (info->output_scanline < info->output_height) {
828        // jpeg_read_scanlines will increase the scanline counter, so we
829        // save the scanline before calling it.
830        int y = info->output_scanline;
831        // Request one scanline: returns 0 or 1 scanlines.
832        if (jpeg_read_scanlines(info, samples, 1) != 1)
833            return false;
834#if USE(QCMSLIB)
835        if (reader->colorTransform() && colorSpace == JCS_RGB)
836            qcms_transform_data(reader->colorTransform(), *samples, *samples, width);
837#endif
838        ImageFrame::PixelData* pixel = buffer.getAddr(0, y);
839        for (int x = 0; x < width; ++pixel, ++x)
840            setPixel<colorSpace>(buffer, pixel, samples, x);
841    }
842
843    buffer.setPixelsChanged(true);
844    return true;
845}
846
847static bool outputRawData(JPEGImageReader* reader, ImagePlanes* imagePlanes)
848{
849    JSAMPARRAY samples = reader->samples();
850    jpeg_decompress_struct* info = reader->info();
851    JSAMPARRAY bufferraw[3];
852    JSAMPROW bufferraw2[32];
853    bufferraw[0] = &bufferraw2[0]; // Y channel rows (8 or 16)
854    bufferraw[1] = &bufferraw2[16]; // U channel rows (8)
855    bufferraw[2] = &bufferraw2[24]; // V channel rows (8)
856    int yWidth = info->output_width;
857    int yHeight = info->output_height;
858    int yMaxH = yHeight - 1;
859    int v = info->cur_comp_info[0]->v_samp_factor;
860    IntSize uvSize = reader->uvSize();
861    int uvMaxH = uvSize.height() - 1;
862    JSAMPROW outputY = static_cast<JSAMPROW>(imagePlanes->plane(0));
863    JSAMPROW outputU = static_cast<JSAMPROW>(imagePlanes->plane(1));
864    JSAMPROW outputV = static_cast<JSAMPROW>(imagePlanes->plane(2));
865    size_t rowBytesY = imagePlanes->rowBytes(0);
866    size_t rowBytesU = imagePlanes->rowBytes(1);
867    size_t rowBytesV = imagePlanes->rowBytes(2);
868
869    int yScanlinesToRead = DCTSIZE * v;
870    JSAMPROW yLastRow = *samples;
871    JSAMPROW uLastRow = yLastRow + 2 * yWidth;
872    JSAMPROW vLastRow = uLastRow + 2 * yWidth;
873    JSAMPROW dummyRow = vLastRow + 2 * yWidth;
874
875    while (info->output_scanline < info->output_height) {
876        // Request 8 or 16 scanlines: returns 0 or more scanlines.
877        bool hasYLastRow(false), hasUVLastRow(false);
878        // Assign 8 or 16 rows of memory to read the Y channel.
879        for (int i = 0; i < yScanlinesToRead; ++i) {
880            int scanline = (info->output_scanline + i);
881            if (scanline < yMaxH) {
882                bufferraw2[i] = &outputY[scanline * rowBytesY];
883            } else if (scanline == yMaxH) {
884                bufferraw2[i] = yLastRow;
885                hasYLastRow = true;
886            } else {
887                bufferraw2[i] = dummyRow;
888            }
889        }
890        int scaledScanline = info->output_scanline / v;
891        // Assign 8 rows of memory to read the U and V channels.
892        for (int i = 0; i < 8; ++i) {
893            int scanline = (scaledScanline + i);
894            if (scanline < uvMaxH) {
895                bufferraw2[16 + i] = &outputU[scanline * rowBytesU];
896                bufferraw2[24 + i] = &outputV[scanline * rowBytesV];
897            } else if (scanline == uvMaxH) {
898                bufferraw2[16 + i] = uLastRow;
899                bufferraw2[24 + i] = vLastRow;
900                hasUVLastRow = true;
901            } else {
902                bufferraw2[16 + i] = dummyRow;
903                bufferraw2[24 + i] = dummyRow;
904            }
905        }
906        JDIMENSION scanlinesRead = jpeg_read_raw_data(info, bufferraw, yScanlinesToRead);
907
908        if (scanlinesRead == 0)
909            return false;
910
911        if (hasYLastRow) {
912            memcpy(&outputY[yMaxH * rowBytesY], yLastRow, yWidth);
913        }
914        if (hasUVLastRow) {
915            memcpy(&outputU[uvMaxH * rowBytesU], uLastRow, uvSize.width());
916            memcpy(&outputV[uvMaxH * rowBytesV], vLastRow, uvSize.width());
917        }
918    }
919
920    info->output_scanline = std::min(info->output_scanline, info->output_height);
921
922    return true;
923}
924
925bool JPEGImageDecoder::outputScanlines()
926{
927    if (hasImagePlanes()) {
928        return outputRawData(m_reader.get(), m_imagePlanes.get());
929    }
930
931    if (m_frameBufferCache.isEmpty())
932        return false;
933
934    jpeg_decompress_struct* info = m_reader->info();
935
936    // Initialize the framebuffer if needed.
937    ImageFrame& buffer = m_frameBufferCache[0];
938    if (buffer.status() == ImageFrame::FrameEmpty) {
939        ASSERT(info->output_width == static_cast<JDIMENSION>(m_decodedSize.width()));
940        ASSERT(info->output_height == static_cast<JDIMENSION>(m_decodedSize.height()));
941
942        if (!buffer.setSize(info->output_width, info->output_height))
943            return setFailed();
944        buffer.setStatus(ImageFrame::FramePartial);
945        // The buffer is transparent outside the decoded area while the image is
946        // loading. The completed image will be marked fully opaque in jpegComplete().
947        buffer.setHasAlpha(true);
948
949        // For JPEGs, the frame always fills the entire image.
950        buffer.setOriginalFrameRect(IntRect(IntPoint(), size()));
951    }
952
953#if defined(TURBO_JPEG_RGB_SWIZZLE)
954    if (turboSwizzled(info->out_color_space)) {
955        while (info->output_scanline < info->output_height) {
956            unsigned char* row = reinterpret_cast<unsigned char*>(buffer.getAddr(0, info->output_scanline));
957            if (jpeg_read_scanlines(info, &row, 1) != 1)
958                return false;
959#if USE(QCMSLIB)
960            if (qcms_transform* transform = m_reader->colorTransform())
961                qcms_transform_data_type(transform, row, row, info->output_width, rgbOutputColorSpace() == JCS_EXT_BGRA ? QCMS_OUTPUT_BGRX : QCMS_OUTPUT_RGBX);
962#endif
963        }
964        buffer.setPixelsChanged(true);
965        return true;
966    }
967#endif
968
969    switch (info->out_color_space) {
970    case JCS_RGB:
971        return outputRows<JCS_RGB>(m_reader.get(), buffer);
972    case JCS_CMYK:
973        return outputRows<JCS_CMYK>(m_reader.get(), buffer);
974    default:
975        ASSERT_NOT_REACHED();
976    }
977
978    return setFailed();
979}
980
981void JPEGImageDecoder::jpegComplete()
982{
983    if (m_frameBufferCache.isEmpty())
984        return;
985
986    // Hand back an appropriately sized buffer, even if the image ended up being
987    // empty.
988    ImageFrame& buffer = m_frameBufferCache[0];
989    buffer.setHasAlpha(false);
990    buffer.setStatus(ImageFrame::FrameComplete);
991}
992
993void JPEGImageDecoder::decode(bool onlySize)
994{
995    if (failed())
996        return;
997
998    if (!m_reader) {
999        m_reader = adoptPtr(new JPEGImageReader(this));
1000    }
1001
1002    // If we couldn't decode the image but we've received all the data, decoding
1003    // has failed.
1004    if (!m_reader->decode(*m_data, onlySize) && isAllDataReceived())
1005        setFailed();
1006    // If we're done decoding the image, we don't need the JPEGImageReader
1007    // anymore.  (If we failed, |m_reader| has already been cleared.)
1008    else if ((!m_frameBufferCache.isEmpty() && (m_frameBufferCache[0].status() == ImageFrame::FrameComplete)) || (hasImagePlanes() && !onlySize))
1009        m_reader.clear();
1010}
1011
1012}
1013