2 * Copyright (C) 2006 Apple Computer, Inc.
4 * Portions are Copyright (C) 2001-6 mozilla.org
7 * Stuart Parmenter <stuart@mozilla.com>
9 * Copyright (C) 2007-2009 Torch Mobile, Inc.
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.
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.
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
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.
41 #include "platform/image-decoders/jpeg/JPEGImageDecoder.h"
43 #include "platform/PlatformInstrumentation.h"
44 #include "wtf/PassOwnPtr.h"
45 #include "wtf/dtoa/utils.h"
48 #include <stdio.h> // jpeglib.h needs stdio FILE.
59 #if CPU(BIG_ENDIAN) || CPU(MIDDLE_ENDIAN)
60 #error Blink assumes a little-endian target.
63 #if defined(JCS_ALPHA_EXTENSIONS)
64 #define TURBO_JPEG_RGB_SWIZZLE
65 #if SK_B32_SHIFT // Output little-endian RGBA pixels (Android).
66 inline J_COLOR_SPACE rgbOutputColorSpace() { return JCS_EXT_RGBA; }
67 #else // Output little-endian BGRA pixels.
68 inline J_COLOR_SPACE rgbOutputColorSpace() { return JCS_EXT_BGRA; }
70 inline bool turboSwizzled(J_COLOR_SPACE colorSpace) { return colorSpace == JCS_EXT_RGBA || colorSpace == JCS_EXT_BGRA; }
71 inline bool colorSpaceHasAlpha(J_COLOR_SPACE colorSpace) { return turboSwizzled(colorSpace); }
73 inline J_COLOR_SPACE rgbOutputColorSpace() { return JCS_RGB; }
74 inline bool colorSpaceHasAlpha(J_COLOR_SPACE) { return false; }
77 #if USE(LOW_QUALITY_IMAGE_NO_JPEG_DITHERING)
78 inline J_DCT_METHOD dctMethod() { return JDCT_IFAST; }
79 inline J_DITHER_MODE ditherMode() { return JDITHER_NONE; }
81 inline J_DCT_METHOD dctMethod() { return JDCT_ISLOW; }
82 inline J_DITHER_MODE ditherMode() { return JDITHER_FS; }
85 #if USE(LOW_QUALITY_IMAGE_NO_JPEG_FANCY_UPSAMPLING)
86 inline bool doFancyUpsampling() { return false; }
88 inline bool doFancyUpsampling() { return true; }
93 const int exifMarker = JPEG_APP0 + 1;
95 // JPEG only supports a denominator of 8.
96 const unsigned scaleDenominator = 8;
102 struct decoder_error_mgr {
103 struct jpeg_error_mgr pub; // "public" fields for IJG library
104 jmp_buf setjmp_buffer; // For handling catastropic errors
108 JPEG_HEADER, // Reading JFIF headers
109 JPEG_START_DECOMPRESS,
110 JPEG_DECOMPRESS_PROGRESSIVE, // Output progressive pixels
111 JPEG_DECOMPRESS_SEQUENTIAL, // Output sequential pixels
116 enum yuv_subsampling {
126 void init_source(j_decompress_ptr jd);
127 boolean fill_input_buffer(j_decompress_ptr jd);
128 void skip_input_data(j_decompress_ptr jd, long num_bytes);
129 void term_source(j_decompress_ptr jd);
130 void error_exit(j_common_ptr cinfo);
132 // Implementation of a JPEG src object that understands our state machine
133 struct decoder_source_mgr {
134 // public fields; must be first in this struct!
135 struct jpeg_source_mgr pub;
137 JPEGImageReader* decoder;
140 static unsigned readUint16(JOCTET* data, bool isBigEndian)
143 return (GETJOCTET(data[0]) << 8) | GETJOCTET(data[1]);
144 return (GETJOCTET(data[1]) << 8) | GETJOCTET(data[0]);
147 static unsigned readUint32(JOCTET* data, bool 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]);
154 static bool checkExifHeader(jpeg_saved_marker_ptr marker, bool& isBigEndian, unsigned& ifdOffset)
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
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'))))
175 isBigEndian = marker->data[6] == 'M';
176 if (readUint16(marker->data + 8, isBigEndian) != 42)
179 ifdOffset = readUint32(marker->data + 10, isBigEndian);
183 static ImageOrientation readImageOrientation(jpeg_decompress_struct* info)
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) {
192 if (!checkExifHeader(marker, isBigEndian, ifdOffset))
194 const unsigned offsetToTiffData = 6; // Account for 'Exif\0<fill byte>' header.
195 if (marker->data_length < offsetToTiffData || ifdOffset >= marker->data_length - offsetToTiffData)
197 ifdOffset += offsetToTiffData;
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;
208 unsigned tagCount = readUint16(ifd, isBigEndian);
209 ifd += 2; // Skip over the uint16 that was just read.
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));
224 return ImageOrientation();
228 static void readColorProfile(jpeg_decompress_struct* info, ColorProfile& colorProfile)
232 unsigned profileLength;
234 if (!read_icc_profile(info, &profile, &profileLength))
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;
247 ASSERT(colorProfile.isEmpty());
249 colorProfile.append(profileData, profileLength);
255 static IntSize computeUVSize(const jpeg_decompress_struct* info)
257 int h = info->cur_comp_info[0]->h_samp_factor;
258 int v = info->cur_comp_info[0]->v_samp_factor;
259 return IntSize((info->output_width + h - 1) / h, (info->output_height + v - 1) / v);
262 static yuv_subsampling getYUVSubsampling(const jpeg_decompress_struct& info)
265 && (info.num_components == 3)
266 && (info.scale_denom <= 8)
267 && (info.cur_comp_info[1]->h_samp_factor == 1)
268 && (info.cur_comp_info[1]->v_samp_factor == 1)
269 && (info.cur_comp_info[2]->h_samp_factor == 1)
270 && (info.cur_comp_info[2]->v_samp_factor == 1)) {
271 int h = info.cur_comp_info[0]->h_samp_factor;
272 int v = info.cur_comp_info[0]->v_samp_factor;
273 // 4:4:4 : (h == 1) && (v == 1)
274 // 4:4:0 : (h == 1) && (v == 2)
275 // 4:2:2 : (h == 2) && (v == 1)
276 // 4:2:0 : (h == 2) && (v == 2)
277 // 4:1:1 : (h == 4) && (v == 1)
278 // 4:1:0 : (h == 4) && (v == 2)
307 class JPEGImageReader {
308 WTF_MAKE_FAST_ALLOCATED;
310 JPEGImageReader(JPEGImageDecoder* decoder)
314 , m_state(JPEG_HEADER)
320 memset(&m_info, 0, sizeof(jpeg_decompress_struct));
322 // We set up the normal JPEG error routines, then override error_exit.
323 m_info.err = jpeg_std_error(&m_err.pub);
324 m_err.pub.error_exit = error_exit;
326 // Allocate and initialize JPEG decompression object.
327 jpeg_create_decompress(&m_info);
329 decoder_source_mgr* src = 0;
331 src = (decoder_source_mgr*)fastZeroedMalloc(sizeof(decoder_source_mgr));
333 m_state = JPEG_ERROR;
338 m_info.src = (jpeg_source_mgr*)src;
340 // Set up callback functions.
341 src->pub.init_source = init_source;
342 src->pub.fill_input_buffer = fill_input_buffer;
343 src->pub.skip_input_data = skip_input_data;
344 src->pub.resync_to_restart = jpeg_resync_to_restart;
345 src->pub.term_source = term_source;
349 // Retain ICC color profile markers for color management.
350 setup_read_icc_profile(&m_info);
353 // Keep APP1 blocks, for obtaining exif data.
354 jpeg_save_markers(&m_info, exifMarker, 0xFFFF);
364 decoder_source_mgr* src = (decoder_source_mgr*)m_info.src;
371 qcms_transform_release(m_transform);
374 jpeg_destroy_decompress(&m_info);
377 void skipBytes(long numBytes)
379 decoder_source_mgr* src = (decoder_source_mgr*)m_info.src;
380 long bytesToSkip = std::min(numBytes, (long)src->pub.bytes_in_buffer);
381 src->pub.bytes_in_buffer -= (size_t)bytesToSkip;
382 src->pub.next_input_byte += bytesToSkip;
384 m_bytesToSkip = std::max(numBytes - bytesToSkip, static_cast<long>(0));
387 bool decode(const SharedBuffer& data, bool onlySize)
389 unsigned newByteCount = data.size() - m_bufferLength;
390 unsigned readOffset = m_bufferLength - m_info.src->bytes_in_buffer;
392 m_info.src->bytes_in_buffer += newByteCount;
393 m_info.src->next_input_byte = (JOCTET*)(data.data()) + readOffset;
395 // If we still have bytes to skip, try to skip those now.
397 skipBytes(m_bytesToSkip);
399 m_bufferLength = data.size();
401 // We need to do the setjmp here. Otherwise bad things will happen
402 if (setjmp(m_err.setjmp_buffer))
403 return m_decoder->setFailed();
407 // Read file parameters with jpeg_read_header().
408 if (jpeg_read_header(&m_info, true) == JPEG_SUSPENDED)
409 return false; // I/O suspension.
411 switch (m_info.jpeg_color_space) {
413 // libjpeg can convert YCbCr image pixels to RGB.
414 m_info.out_color_space = rgbOutputColorSpace();
415 if (m_decoder->YUVDecoding() && (getYUVSubsampling(m_info) != YUV_UNKNOWN)) {
416 m_info.out_color_space = JCS_YCbCr;
417 m_info.raw_data_out = TRUE;
422 // libjpeg can convert GRAYSCALE image pixels to RGB.
423 m_info.out_color_space = rgbOutputColorSpace();
424 #if defined(TURBO_JPEG_RGB_SWIZZLE)
425 if (m_info.saw_JFIF_marker)
427 // FIXME: Swizzle decoding does not support Adobe transform=0
428 // images (yet), so revert to using JSC_RGB in that case.
429 if (m_info.saw_Adobe_marker && !m_info.Adobe_transform)
430 m_info.out_color_space = JCS_RGB;
435 // libjpeg can convert YCCK to CMYK, but neither to RGB, so we
436 // manually convert CMKY to RGB.
437 m_info.out_color_space = JCS_CMYK;
440 return m_decoder->setFailed();
443 m_state = JPEG_START_DECOMPRESS;
445 // We can fill in the size now that the header is available.
446 if (!m_decoder->setSize(m_info.image_width, m_info.image_height))
449 // Calculate and set decoded size.
450 m_info.scale_num = m_decoder->desiredScaleNumerator();
451 m_info.scale_denom = scaleDenominator;
452 jpeg_calc_output_dimensions(&m_info);
453 m_decoder->setDecodedSize(m_info.output_width, m_info.output_height);
455 m_decoder->setOrientation(readImageOrientation(info()));
458 // Allow color management of the decoded RGBA pixels if possible.
459 if (!m_decoder->ignoresGammaAndColorProfile()) {
460 ColorProfile colorProfile;
461 readColorProfile(info(), colorProfile);
462 createColorTransform(colorProfile, colorSpaceHasAlpha(m_info.out_color_space));
463 if (m_transform && m_info.out_color_space == JCS_YCbCr) {
464 m_info.out_color_space = rgbOutputColorSpace();
465 m_info.raw_data_out = FALSE;
467 #if defined(TURBO_JPEG_RGB_SWIZZLE)
468 // Input RGBA data to qcms. Note: restored to BGRA on output.
469 if (m_transform && m_info.out_color_space == JCS_EXT_BGRA)
470 m_info.out_color_space = JCS_EXT_RGBA;
472 m_decoder->setHasColorProfile(!!m_transform);
475 // Don't allocate a giant and superfluous memory buffer when the
476 // image is a sequential JPEG.
477 m_info.buffered_image = jpeg_has_multiple_scans(&m_info);
480 // We can stop here. Reduce our buffer length and available data.
481 m_bufferLength -= m_info.src->bytes_in_buffer;
482 m_info.src->bytes_in_buffer = 0;
487 case JPEG_START_DECOMPRESS:
488 // Set parameters for decompression.
489 // FIXME -- Should reset dct_method and dither mode for final pass
490 // of progressive JPEG.
491 m_info.dct_method = dctMethod();
492 m_info.dither_mode = ditherMode();
493 m_info.do_fancy_upsampling = doFancyUpsampling();
494 m_info.enable_2pass_quant = false;
495 m_info.do_block_smoothing = true;
497 // Make a one-row-high sample array that will go away when done with
498 // image. Always make it big enough to hold an RGB row. Since this
499 // uses the IJG memory manager, it must be allocated before the call
500 // to jpeg_start_compress().
501 // FIXME: note that some output color spaces do not need the samples
502 // buffer. Remove this allocation for those color spaces.
503 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);
505 // Start decompressor.
506 if (!jpeg_start_decompress(&m_info))
507 return false; // I/O suspension.
509 // If this is a progressive JPEG ...
510 m_state = (m_info.buffered_image) ? JPEG_DECOMPRESS_PROGRESSIVE : JPEG_DECOMPRESS_SEQUENTIAL;
513 case JPEG_DECOMPRESS_SEQUENTIAL:
514 if (m_state == JPEG_DECOMPRESS_SEQUENTIAL) {
516 if (!m_decoder->outputScanlines())
517 return false; // I/O suspension.
519 // If we've completed image output...
520 ASSERT(m_info.output_scanline == m_info.output_height);
525 case JPEG_DECOMPRESS_PROGRESSIVE:
526 if (m_state == JPEG_DECOMPRESS_PROGRESSIVE) {
529 status = jpeg_consume_input(&m_info);
530 } while ((status != JPEG_SUSPENDED) && (status != JPEG_REACHED_EOI));
533 if (!m_info.output_scanline) {
534 int scan = m_info.input_scan_number;
536 // If we haven't displayed anything yet
537 // (output_scan_number == 0) and we have enough data for
538 // a complete scan, force output of the last full scan.
539 if (!m_info.output_scan_number && (scan > 1) && (status != JPEG_REACHED_EOI))
542 if (!jpeg_start_output(&m_info, scan))
543 return false; // I/O suspension.
546 if (m_info.output_scanline == 0xffffff)
547 m_info.output_scanline = 0;
549 // If outputScanlines() fails, it deletes |this|. Therefore,
550 // copy the decoder pointer and use it to check for failure
551 // to avoid member access in the failure case.
552 JPEGImageDecoder* decoder = m_decoder;
553 if (!decoder->outputScanlines()) {
554 if (decoder->failed()) // Careful; |this| is deleted.
556 if (!m_info.output_scanline)
557 // Didn't manage to read any lines - flag so we
558 // don't call jpeg_start_output() multiple times for
560 m_info.output_scanline = 0xffffff;
561 return false; // I/O suspension.
564 if (m_info.output_scanline == m_info.output_height) {
565 if (!jpeg_finish_output(&m_info))
566 return false; // I/O suspension.
568 if (jpeg_input_complete(&m_info) && (m_info.input_scan_number == m_info.output_scan_number))
571 m_info.output_scanline = 0;
580 // Finish decompression.
581 return jpeg_finish_decompress(&m_info);
584 // We can get here if the constructor failed.
585 return m_decoder->setFailed();
591 jpeg_decompress_struct* info() { return &m_info; }
592 JSAMPARRAY samples() const { return m_samples; }
593 JPEGImageDecoder* decoder() { return m_decoder; }
595 qcms_transform* colorTransform() const { return m_transform; }
597 void createColorTransform(const ColorProfile& colorProfile, bool hasAlpha)
600 qcms_transform_release(m_transform);
603 if (colorProfile.isEmpty())
605 qcms_profile* deviceProfile = ImageDecoder::qcmsOutputDeviceProfile();
608 qcms_profile* inputProfile = qcms_profile_from_memory(colorProfile.data(), colorProfile.size());
611 // We currently only support color profiles for RGB profiled images.
612 ASSERT(icSigRgbData == qcms_profile_get_color_space(inputProfile));
613 qcms_data_type dataFormat = hasAlpha ? QCMS_DATA_RGBA_8 : QCMS_DATA_RGB_8;
614 // FIXME: Don't force perceptual intent if the image profile contains an intent.
615 m_transform = qcms_transform_create(inputProfile, dataFormat, deviceProfile, dataFormat, QCMS_INTENT_PERCEPTUAL);
616 qcms_profile_release(inputProfile);
621 JPEGImageDecoder* m_decoder;
622 unsigned m_bufferLength;
625 jpeg_decompress_struct m_info;
626 decoder_error_mgr m_err;
629 JSAMPARRAY m_samples;
632 qcms_transform* m_transform;
636 // Override the standard error method in the IJG JPEG decoder code.
637 void error_exit(j_common_ptr cinfo)
639 // Return control to the setjmp point.
640 decoder_error_mgr *err = reinterpret_cast_ptr<decoder_error_mgr *>(cinfo->err);
641 longjmp(err->setjmp_buffer, -1);
644 void init_source(j_decompress_ptr)
648 void skip_input_data(j_decompress_ptr jd, long num_bytes)
650 decoder_source_mgr *src = (decoder_source_mgr *)jd->src;
651 src->decoder->skipBytes(num_bytes);
654 boolean fill_input_buffer(j_decompress_ptr)
656 // Our decode step always sets things up properly, so if this method is ever
657 // called, then we have hit the end of the buffer. A return value of false
658 // indicates that we have no data to supply yet.
662 void term_source(j_decompress_ptr jd)
664 decoder_source_mgr *src = (decoder_source_mgr *)jd->src;
665 src->decoder->decoder()->jpegComplete();
668 JPEGImageDecoder::JPEGImageDecoder(ImageSource::AlphaOption alphaOption,
669 ImageSource::GammaAndColorProfileOption gammaAndColorProfileOption,
670 size_t maxDecodedBytes)
671 : ImageDecoder(alphaOption, gammaAndColorProfileOption, maxDecodedBytes)
672 , m_hasColorProfile(false)
676 JPEGImageDecoder::~JPEGImageDecoder()
680 bool JPEGImageDecoder::isSizeAvailable()
682 if (!ImageDecoder::isSizeAvailable())
685 return ImageDecoder::isSizeAvailable();
688 bool JPEGImageDecoder::setSize(unsigned width, unsigned height)
690 if (!ImageDecoder::setSize(width, height))
693 if (!desiredScaleNumerator())
696 setDecodedSize(width, height);
700 void JPEGImageDecoder::setDecodedSize(unsigned width, unsigned height)
702 m_decodedSize = IntSize(width, height);
705 IntSize JPEGImageDecoder::decodedYUVSize(int component) const
707 if (((component == 1) || (component == 2)) && m_reader.get()) { // Asking for U or V
708 const jpeg_decompress_struct* info = m_reader->info();
709 if (info && (info->out_color_space == JCS_YCbCr)) {
710 return computeUVSize(info);
714 return m_decodedSize;
717 unsigned JPEGImageDecoder::desiredScaleNumerator() const
719 size_t originalBytes = size().width() * size().height() * 4;
720 if (originalBytes <= m_maxDecodedBytes) {
721 return scaleDenominator;
724 // Downsample according to the maximum decoded size.
725 unsigned scaleNumerator = static_cast<unsigned>(floor(sqrt(
726 // MSVC needs explicit parameter type for sqrt().
727 static_cast<float>(m_maxDecodedBytes * scaleDenominator * scaleDenominator / originalBytes))));
729 return scaleNumerator;
732 bool JPEGImageDecoder::decodeToYUV()
734 PlatformInstrumentation::willDecodeImage("JPEG");
736 PlatformInstrumentation::didDecodeImage();
740 ImageFrame* JPEGImageDecoder::frameBufferAtIndex(size_t index)
745 if (m_frameBufferCache.isEmpty()) {
746 m_frameBufferCache.resize(1);
747 m_frameBufferCache[0].setPremultiplyAlpha(m_premultiplyAlpha);
750 ImageFrame& frame = m_frameBufferCache[0];
751 if (frame.status() != ImageFrame::FrameComplete) {
752 PlatformInstrumentation::willDecodeImage("JPEG");
754 PlatformInstrumentation::didDecodeImage();
757 frame.notifyBitmapIfPixelsChanged();
761 bool JPEGImageDecoder::setFailed()
764 return ImageDecoder::setFailed();
767 void JPEGImageDecoder::setImagePlanes(OwnPtr<ImagePlanes>& imagePlanes)
769 m_imagePlanes = imagePlanes.release();
772 template <J_COLOR_SPACE colorSpace> void setPixel(ImageFrame& buffer, ImageFrame::PixelData* pixel, JSAMPARRAY samples, int column)
774 ASSERT_NOT_REACHED();
777 template <> void setPixel<JCS_RGB>(ImageFrame& buffer, ImageFrame::PixelData* pixel, JSAMPARRAY samples, int column)
779 JSAMPLE* jsample = *samples + column * 3;
780 buffer.setRGBARaw(pixel, jsample[0], jsample[1], jsample[2], 255);
783 template <> void setPixel<JCS_CMYK>(ImageFrame& buffer, ImageFrame::PixelData* pixel, JSAMPARRAY samples, int column)
785 JSAMPLE* jsample = *samples + column * 4;
787 // Source is 'Inverted CMYK', output is RGB.
788 // See: http://www.easyrgb.com/math.php?MATH=M12#text12
789 // Or: http://www.ilkeratalay.com/colorspacesfaq.php#rgb
791 // X = X * (1 - K ) + K [for X = C, M, or Y]
792 // Thus, from Inverted CMYK to CMY is:
793 // X = (1-iX) * (1 - (1-iK)) + (1-iK) => 1 - iX*iK
794 // From CMY (0..1) to RGB (0..1):
795 // R = 1 - C => 1 - (1 - iC*iK) => iC*iK [G and B similar]
796 unsigned k = jsample[3];
797 buffer.setRGBARaw(pixel, jsample[0] * k / 255, jsample[1] * k / 255, jsample[2] * k / 255, 255);
800 template <J_COLOR_SPACE colorSpace> bool outputRows(JPEGImageReader* reader, ImageFrame& buffer)
802 JSAMPARRAY samples = reader->samples();
803 jpeg_decompress_struct* info = reader->info();
804 int width = info->output_width;
806 while (info->output_scanline < info->output_height) {
807 // jpeg_read_scanlines will increase the scanline counter, so we
808 // save the scanline before calling it.
809 int y = info->output_scanline;
810 // Request one scanline: returns 0 or 1 scanlines.
811 if (jpeg_read_scanlines(info, samples, 1) != 1)
814 if (reader->colorTransform() && colorSpace == JCS_RGB)
815 qcms_transform_data(reader->colorTransform(), *samples, *samples, width);
817 ImageFrame::PixelData* pixel = buffer.getAddr(0, y);
818 for (int x = 0; x < width; ++pixel, ++x)
819 setPixel<colorSpace>(buffer, pixel, samples, x);
822 buffer.setPixelsChanged(true);
826 static bool outputRawData(JPEGImageReader* reader, ImagePlanes* imagePlanes)
828 JSAMPARRAY samples = reader->samples();
829 jpeg_decompress_struct* info = reader->info();
830 JSAMPARRAY bufferraw[3];
831 JSAMPROW bufferraw2[32];
832 bufferraw[0] = &bufferraw2[0]; // Y channel rows (8 or 16)
833 bufferraw[1] = &bufferraw2[16]; // U channel rows (8)
834 bufferraw[2] = &bufferraw2[24]; // V channel rows (8)
835 int yWidth = info->output_width;
836 int yHeight = info->output_height;
837 int yMaxH = yHeight - 1;
838 int v = info->cur_comp_info[0]->v_samp_factor;
839 IntSize uvSize = computeUVSize(info);
840 int uvMaxH = uvSize.height() - 1;
841 JSAMPROW outputY = static_cast<JSAMPROW>(imagePlanes->plane(0));
842 JSAMPROW outputU = static_cast<JSAMPROW>(imagePlanes->plane(1));
843 JSAMPROW outputV = static_cast<JSAMPROW>(imagePlanes->plane(2));
844 size_t rowBytesY = imagePlanes->rowBytes(0);
845 size_t rowBytesU = imagePlanes->rowBytes(1);
846 size_t rowBytesV = imagePlanes->rowBytes(2);
848 int yScanlinesToRead = DCTSIZE * v;
849 JSAMPROW yLastRow = *samples;
850 JSAMPROW uLastRow = yLastRow + 2 * yWidth;
851 JSAMPROW vLastRow = uLastRow + 2 * yWidth;
852 JSAMPROW dummyRow = vLastRow + 2 * yWidth;
854 while (info->output_scanline < info->output_height) {
855 // Request 8 or 16 scanlines: returns 0 or more scanlines.
856 bool hasYLastRow(false), hasUVLastRow(false);
857 // Assign 8 or 16 rows of memory to read the Y channel.
858 for (int i = 0; i < yScanlinesToRead; ++i) {
859 int scanline = (info->output_scanline + i);
860 if (scanline < yMaxH) {
861 bufferraw2[i] = &outputY[scanline * rowBytesY];
862 } else if (scanline == yMaxH) {
863 bufferraw2[i] = yLastRow;
866 bufferraw2[i] = dummyRow;
869 int scaledScanline = info->output_scanline / v;
870 // Assign 8 rows of memory to read the U and V channels.
871 for (int i = 0; i < 8; ++i) {
872 int scanline = (scaledScanline + i);
873 if (scanline < uvMaxH) {
874 bufferraw2[16 + i] = &outputU[scanline * rowBytesU];
875 bufferraw2[24 + i] = &outputV[scanline * rowBytesV];
876 } else if (scanline == uvMaxH) {
877 bufferraw2[16 + i] = uLastRow;
878 bufferraw2[24 + i] = vLastRow;
881 bufferraw2[16 + i] = dummyRow;
882 bufferraw2[24 + i] = dummyRow;
885 JDIMENSION scanlinesRead = jpeg_read_raw_data(info, bufferraw, yScanlinesToRead);
887 if (scanlinesRead == 0)
891 memcpy(&outputY[yMaxH * rowBytesY], yLastRow, yWidth);
894 memcpy(&outputU[uvMaxH * rowBytesU], uLastRow, uvSize.width());
895 memcpy(&outputV[uvMaxH * rowBytesV], vLastRow, uvSize.width());
899 info->output_scanline = std::min(info->output_scanline, info->output_height);
904 bool JPEGImageDecoder::outputScanlines()
906 if (m_frameBufferCache.isEmpty())
909 jpeg_decompress_struct* info = m_reader->info();
911 if (m_imagePlanes.get()) {
912 return outputRawData(m_reader.get(), m_imagePlanes.get());
915 // Initialize the framebuffer if needed.
916 ImageFrame& buffer = m_frameBufferCache[0];
917 if (buffer.status() == ImageFrame::FrameEmpty) {
918 ASSERT(info->output_width == static_cast<JDIMENSION>(m_decodedSize.width()));
919 ASSERT(info->output_height == static_cast<JDIMENSION>(m_decodedSize.height()));
921 if (!buffer.setSize(info->output_width, info->output_height))
923 buffer.setStatus(ImageFrame::FramePartial);
924 // The buffer is transparent outside the decoded area while the image is
925 // loading. The completed image will be marked fully opaque in jpegComplete().
926 buffer.setHasAlpha(true);
928 // For JPEGs, the frame always fills the entire image.
929 buffer.setOriginalFrameRect(IntRect(IntPoint(), size()));
932 #if defined(TURBO_JPEG_RGB_SWIZZLE)
933 if (turboSwizzled(info->out_color_space)) {
934 while (info->output_scanline < info->output_height) {
935 unsigned char* row = reinterpret_cast<unsigned char*>(buffer.getAddr(0, info->output_scanline));
936 if (jpeg_read_scanlines(info, &row, 1) != 1)
939 if (qcms_transform* transform = m_reader->colorTransform())
940 qcms_transform_data_type(transform, row, row, info->output_width, rgbOutputColorSpace() == JCS_EXT_BGRA ? QCMS_OUTPUT_BGRX : QCMS_OUTPUT_RGBX);
943 buffer.setPixelsChanged(true);
948 switch (info->out_color_space) {
950 return outputRows<JCS_RGB>(m_reader.get(), buffer);
952 return outputRows<JCS_CMYK>(m_reader.get(), buffer);
954 ASSERT_NOT_REACHED();
960 void JPEGImageDecoder::jpegComplete()
962 if (m_frameBufferCache.isEmpty())
965 // Hand back an appropriately sized buffer, even if the image ended up being
967 ImageFrame& buffer = m_frameBufferCache[0];
968 buffer.setHasAlpha(false);
969 buffer.setStatus(ImageFrame::FrameComplete);
972 void JPEGImageDecoder::decode(bool onlySize)
978 m_reader = adoptPtr(new JPEGImageReader(this));
981 // If we couldn't decode the image but we've received all the data, decoding
983 if (!m_reader->decode(*m_data, onlySize) && isAllDataReceived())
985 // If we're done decoding the image, we don't need the JPEGImageReader
986 // anymore. (If we failed, |m_reader| has already been cleared.)
987 else if (!m_frameBufferCache.isEmpty() && (m_frameBufferCache[0].status() == ImageFrame::FrameComplete))