bool JPEGImageDecoder::outputScanlines()
{
if (m_frameBufferCache.isEmpty())
return false;
// Initialize the framebuffer if needed.
ImageFrame& buffer = m_frameBufferCache[0];
if (buffer.status() == ImageFrame::FrameEmpty) {
if (!buffer.setSize(scaledSize().width(), scaledSize().height()))
return setFailed();
buffer.setStatus(ImageFrame::FramePartial);
// The buffer is transparent outside the decoded area while the image is
// loading. The completed image will be marked fully opaque in jpegComplete().
buffer.setHasAlpha(true);
buffer.setColorProfile(m_colorProfile);
// For JPEGs, the frame always fills the entire image.
buffer.setOriginalFrameRect(IntRect(IntPoint(), size()));
}
jpeg_decompress_struct* info = m_reader->info();
#if defined(TURBO_JPEG_RGB_SWIZZLE)
if (!m_scaled && turboSwizzled(info->out_color_space)) {
while (info->output_scanline < info->output_height) {
unsigned char* row = reinterpret_cast<unsigned char*>(buffer.getAddr(0, info->output_scanline));
if (jpeg_read_scanlines(info, &row, 1) != 1)
return false;
#if USE(QCMSLIB)
if (qcms_transform* transform = m_reader->colorTransform())
qcms_transform_data_type(transform, row, row, info->output_width, rgbOutputColorSpace() == JCS_EXT_BGRA ? QCMS_OUTPUT_BGRX : QCMS_OUTPUT_RGBX);
#endif
}
return true;
}
#endif
switch (info->out_color_space) {
// The code inside outputScanlines<int, bool> will be executed
// for each pixel, so we want to avoid any extra comparisons there.
// That is why we use template and template specializations here so
// the proper code will be generated at compile time.
case JCS_RGB:
return outputScanlines<JCS_RGB>(buffer);
case JCS_CMYK:
return outputScanlines<JCS_CMYK>(buffer);
default:
ASSERT_NOT_REACHED();
}
return setFailed();
}
bool JPEGImageDecoder::outputScanlines()
{
if (m_frameBufferCache.isEmpty())
return false;
jpeg_decompress_struct* info = m_reader->info();
// Initialize the framebuffer if needed.
ImageFrame& buffer = m_frameBufferCache[0];
if (buffer.status() == ImageFrame::FrameEmpty) {
ASSERT(info->output_width == static_cast<JDIMENSION>(m_decodedSize.width()));
ASSERT(info->output_height == static_cast<JDIMENSION>(m_decodedSize.height()));
if (!buffer.setSize(info->output_width, info->output_height))
return setFailed();
buffer.setStatus(ImageFrame::FramePartial);
// The buffer is transparent outside the decoded area while the image is
// loading. The completed image will be marked fully opaque in jpegComplete().
buffer.setHasAlpha(true);
// For JPEGs, the frame always fills the entire image.
buffer.setOriginalFrameRect(IntRect(IntPoint(), size()));
}
#if defined(TURBO_JPEG_RGB_SWIZZLE)
if (turboSwizzled(info->out_color_space)) {
while (info->output_scanline < info->output_height) {
unsigned char* row = reinterpret_cast<unsigned char*>(buffer.getAddr(0, info->output_scanline));
if (jpeg_read_scanlines(info, &row, 1) != 1)
return false;
#if USE(QCMSLIB)
if (qcms_transform* transform = m_reader->colorTransform())
qcms_transform_data_type(transform, row, row, info->output_width, rgbOutputColorSpace() == JCS_EXT_BGRA ? QCMS_OUTPUT_BGRX : QCMS_OUTPUT_RGBX);
#endif
}
buffer.setPixelsChanged(true);
return true;
}
#endif
switch (info->out_color_space) {
case JCS_RGB:
return outputRows<JCS_RGB>(m_reader.get(), buffer);
case JCS_CMYK:
return outputRows<JCS_CMYK>(m_reader.get(), buffer);
default:
ASSERT_NOT_REACHED();
}
return setFailed();
}
bool decode(const SharedBuffer& data, bool onlySize)
{
unsigned newByteCount = data.size() - m_bufferLength;
unsigned readOffset = m_bufferLength - m_info.src->bytes_in_buffer;
m_info.src->bytes_in_buffer += newByteCount;
m_info.src->next_input_byte = (JOCTET*)(data.data()) + readOffset;
// If we still have bytes to skip, try to skip those now.
if (m_bytesToSkip)
skipBytes(m_bytesToSkip);
m_bufferLength = data.size();
// We need to do the setjmp here. Otherwise bad things will happen
if (setjmp(m_err.setjmp_buffer))
return m_decoder->setFailed();
switch (m_state) {
case JPEG_HEADER:
// Read file parameters with jpeg_read_header().
if (jpeg_read_header(&m_info, true) == JPEG_SUSPENDED)
return false; // I/O suspension.
switch (m_info.jpeg_color_space) {
case JCS_GRAYSCALE:
case JCS_RGB:
case JCS_YCbCr:
// libjpeg can convert GRAYSCALE and YCbCr image pixels to RGB.
m_info.out_color_space = rgbOutputColorSpace();
#if defined(TURBO_JPEG_RGB_SWIZZLE)
if (m_info.saw_JFIF_marker)
break;
// FIXME: Swizzle decoding does not support Adobe transform=0
// images (yet), so revert to using JSC_RGB in that case.
if (m_info.saw_Adobe_marker && !m_info.Adobe_transform)
m_info.out_color_space = JCS_RGB;
#endif
break;
case JCS_CMYK:
case JCS_YCCK:
// libjpeg can convert YCCK to CMYK, but neither to RGB, so we
// manually convert CMKY to RGB.
m_info.out_color_space = JCS_CMYK;
break;
default:
return m_decoder->setFailed();
}
m_state = JPEG_START_DECOMPRESS;
// We can fill in the size now that the header is available.
if (!m_decoder->setSize(m_info.image_width, m_info.image_height))
return false;
// Calculate and set decoded size.
m_info.scale_num = m_decoder->desiredScaleNumerator();
m_info.scale_denom = scaleDenominator;
jpeg_calc_output_dimensions(&m_info);
m_decoder->setDecodedSize(m_info.output_width, m_info.output_height);
m_decoder->setOrientation(readImageOrientation(info()));
#if USE(QCMSLIB)
// Allow color management of the decoded RGBA pixels if possible.
if (!m_decoder->ignoresGammaAndColorProfile()) {
ColorProfile colorProfile;
readColorProfile(info(), colorProfile);
createColorTransform(colorProfile, colorSpaceHasAlpha(m_info.out_color_space));
#if defined(TURBO_JPEG_RGB_SWIZZLE)
// Input RGBA data to qcms. Note: restored to BGRA on output.
if (m_transform && m_info.out_color_space == JCS_EXT_BGRA)
m_info.out_color_space = JCS_EXT_RGBA;
#endif
}
#endif
// Don't allocate a giant and superfluous memory buffer when the
// image is a sequential JPEG.
m_info.buffered_image = jpeg_has_multiple_scans(&m_info);
if (onlySize) {
// We can stop here. Reduce our buffer length and available data.
m_bufferLength -= m_info.src->bytes_in_buffer;
m_info.src->bytes_in_buffer = 0;
return true;
}
// FALL THROUGH
case JPEG_START_DECOMPRESS:
// Set parameters for decompression.
// FIXME -- Should reset dct_method and dither mode for final pass
// of progressive JPEG.
m_info.dct_method = dctMethod();
m_info.dither_mode = ditherMode();
m_info.do_fancy_upsampling = doFancyUpsampling();
m_info.enable_2pass_quant = false;
m_info.do_block_smoothing = true;
// Make a one-row-high sample array that will go away when done with
// image. Always make it big enough to hold an RGB row. Since this
// uses the IJG memory manager, it must be allocated before the call
// to jpeg_start_compress().
// FIXME: note that some output color spaces do not need the samples
// buffer. Remove this allocation for those color spaces.
m_samples = (*m_info.mem->alloc_sarray)(reinterpret_cast<j_common_ptr>(&m_info), JPOOL_IMAGE, m_info.output_width * 4, 1);
// Start decompressor.
if (!jpeg_start_decompress(&m_info))
return false; // I/O suspension.
// If this is a progressive JPEG ...
m_state = (m_info.buffered_image) ? JPEG_DECOMPRESS_PROGRESSIVE : JPEG_DECOMPRESS_SEQUENTIAL;
// FALL THROUGH
case JPEG_DECOMPRESS_SEQUENTIAL:
if (m_state == JPEG_DECOMPRESS_SEQUENTIAL) {
if (!m_decoder->outputScanlines())
return false; // I/O suspension.
// If we've completed image output...
ASSERT(m_info.output_scanline == m_info.output_height);
m_state = JPEG_DONE;
}
// FALL THROUGH
case JPEG_DECOMPRESS_PROGRESSIVE:
if (m_state == JPEG_DECOMPRESS_PROGRESSIVE) {
int status;
do {
status = jpeg_consume_input(&m_info);
} while ((status != JPEG_SUSPENDED) && (status != JPEG_REACHED_EOI));
for (;;) {
if (!m_info.output_scanline) {
int scan = m_info.input_scan_number;
// If we haven't displayed anything yet
// (output_scan_number == 0) and we have enough data for
// a complete scan, force output of the last full scan.
if (!m_info.output_scan_number && (scan > 1) && (status != JPEG_REACHED_EOI))
--scan;
if (!jpeg_start_output(&m_info, scan))
return false; // I/O suspension.
}
if (m_info.output_scanline == 0xffffff)
m_info.output_scanline = 0;
// If outputScanlines() fails, it deletes |this|. Therefore,
// copy the decoder pointer and use it to check for failure
// to avoid member access in the failure case.
JPEGImageDecoder* decoder = m_decoder;
if (!decoder->outputScanlines()) {
if (decoder->failed()) // Careful; |this| is deleted.
return false;
if (!m_info.output_scanline)
// Didn't manage to read any lines - flag so we
// don't call jpeg_start_output() multiple times for
// the same scan.
m_info.output_scanline = 0xffffff;
return false; // I/O suspension.
}
if (m_info.output_scanline == m_info.output_height) {
if (!jpeg_finish_output(&m_info))
return false; // I/O suspension.
if (jpeg_input_complete(&m_info) && (m_info.input_scan_number == m_info.output_scan_number))
break;
m_info.output_scanline = 0;
}
}
m_state = JPEG_DONE;
}
// FALL THROUGH
case JPEG_DONE:
// Finish decompression.
return jpeg_finish_decompress(&m_info);
case JPEG_ERROR:
// We can get here if the constructor failed.
return m_decoder->setFailed();
}
return true;
}
inline bool turboSwizzled(J_COLOR_SPACE colorSpace) { return colorSpace == rgbOutputColorSpace(); }
bool decode(const SharedBuffer& data, bool onlySize)
{
m_decodingSizeOnly = onlySize;
unsigned newByteCount = data.size() - m_bufferLength;
unsigned readOffset = m_bufferLength - m_info.src->bytes_in_buffer;
m_info.src->bytes_in_buffer += newByteCount;
m_info.src->next_input_byte = (JOCTET*)(data.data()) + readOffset;
// If we still have bytes to skip, try to skip those now.
if (m_bytesToSkip)
skipBytes(m_bytesToSkip);
m_bufferLength = data.size();
// We need to do the setjmp here. Otherwise bad things will happen
if (setjmp(m_err.setjmp_buffer))
return m_decoder->setFailed();
switch (m_state) {
case JPEG_HEADER:
// Read file parameters with jpeg_read_header().
if (jpeg_read_header(&m_info, true) == JPEG_SUSPENDED)
return false; // I/O suspension.
switch (m_info.jpeg_color_space) {
case JCS_GRAYSCALE:
case JCS_RGB:
case JCS_YCbCr:
// libjpeg can convert GRAYSCALE and YCbCr image pixels to RGB.
m_info.out_color_space = rgbOutputColorSpace();
break;
case JCS_CMYK:
case JCS_YCCK:
// libjpeg can convert YCCK to CMYK, but neither to RGB, so we
// manually convert CMKY to RGB.
m_info.out_color_space = JCS_CMYK;
break;
default:
return m_decoder->setFailed();
}
// Don't allocate a giant and superfluous memory buffer when the
// image is a sequential JPEG.
m_info.buffered_image = jpeg_has_multiple_scans(&m_info);
// Used to set up image size so arrays can be allocated.
jpeg_calc_output_dimensions(&m_info);
// Make a one-row-high sample array that will go away when done with
// image. Always make it big enough to hold an RGB row. Since this
// uses the IJG memory manager, it must be allocated before the call
// to jpeg_start_compress().
m_samples = (*m_info.mem->alloc_sarray)((j_common_ptr) &m_info, JPOOL_IMAGE, m_info.output_width * 4, 1);
m_state = JPEG_START_DECOMPRESS;
// We can fill in the size now that the header is available.
if (!m_decoder->setSize(m_info.image_width, m_info.image_height))
return false;
// Allow color management of the decoded RGBA pixels if possible.
if (!m_decoder->ignoresGammaAndColorProfile()) {
ColorProfile rgbInputDeviceColorProfile = readColorProfile(info());
if (!rgbInputDeviceColorProfile.isEmpty())
m_decoder->setColorProfile(rgbInputDeviceColorProfile);
}
if (m_decodingSizeOnly) {
// We can stop here. Reduce our buffer length and available
// data.
m_bufferLength -= m_info.src->bytes_in_buffer;
m_info.src->bytes_in_buffer = 0;
return true;
}
// FALL THROUGH
case JPEG_START_DECOMPRESS:
// Set parameters for decompression.
// FIXME -- Should reset dct_method and dither mode for final pass
// of progressive JPEG.
m_info.dct_method = JDCT_ISLOW;
m_info.dither_mode = JDITHER_FS;
m_info.do_fancy_upsampling = true;
m_info.enable_2pass_quant = false;
m_info.do_block_smoothing = true;
// Start decompressor.
if (!jpeg_start_decompress(&m_info))
return false; // I/O suspension.
// If this is a progressive JPEG ...
m_state = (m_info.buffered_image) ? JPEG_DECOMPRESS_PROGRESSIVE : JPEG_DECOMPRESS_SEQUENTIAL;
// FALL THROUGH
case JPEG_DECOMPRESS_SEQUENTIAL:
if (m_state == JPEG_DECOMPRESS_SEQUENTIAL) {
if (!m_decoder->outputScanlines())
return false; // I/O suspension.
// If we've completed image output...
ASSERT(m_info.output_scanline == m_info.output_height);
m_state = JPEG_DONE;
}
// FALL THROUGH
case JPEG_DECOMPRESS_PROGRESSIVE:
if (m_state == JPEG_DECOMPRESS_PROGRESSIVE) {
int status;
do {
status = jpeg_consume_input(&m_info);
} while ((status != JPEG_SUSPENDED) && (status != JPEG_REACHED_EOI));
for (;;) {
if (!m_info.output_scanline) {
int scan = m_info.input_scan_number;
// If we haven't displayed anything yet
// (output_scan_number == 0) and we have enough data for
// a complete scan, force output of the last full scan.
if (!m_info.output_scan_number && (scan > 1) && (status != JPEG_REACHED_EOI))
--scan;
if (!jpeg_start_output(&m_info, scan))
return false; // I/O suspension.
}
if (m_info.output_scanline == 0xffffff)
m_info.output_scanline = 0;
if (!m_decoder->outputScanlines()) {
if (!m_info.output_scanline)
// Didn't manage to read any lines - flag so we
// don't call jpeg_start_output() multiple times for
// the same scan.
m_info.output_scanline = 0xffffff;
return false; // I/O suspension.
}
if (m_info.output_scanline == m_info.output_height) {
if (!jpeg_finish_output(&m_info))
return false; // I/O suspension.
if (jpeg_input_complete(&m_info) && (m_info.input_scan_number == m_info.output_scan_number))
break;
m_info.output_scanline = 0;
}
}
m_state = JPEG_DONE;
}
// FALL THROUGH
case JPEG_DONE:
// Finish decompression.
return jpeg_finish_decompress(&m_info);
case JPEG_ERROR:
// We can get here if the constructor failed.
return m_decoder->setFailed();
}
return true;
}
bool JPEGImageDecoder::outputScanlines()
{
if (m_frameBufferCache.isEmpty())
return false;
// Initialize the framebuffer if needed.
ImageFrame& buffer = m_frameBufferCache[0];
if (buffer.status() == ImageFrame::FrameEmpty) {
if (!buffer.setSize(scaledSize().width(), scaledSize().height()))
return setFailed();
buffer.setStatus(ImageFrame::FramePartial);
// The buffer is transparent outside the decoded area while the image is
// loading. The completed image will be marked fully opaque in jpegComplete().
buffer.setHasAlpha(true);
buffer.setColorProfile(m_colorProfile);
// For JPEGs, the frame always fills the entire image.
buffer.setOriginalFrameRect(IntRect(IntPoint(), size()));
}
jpeg_decompress_struct* info = m_reader->info();
#if !ENABLE(IMAGE_DECODER_DOWN_SAMPLING) && defined(TURBO_JPEG_RGB_SWIZZLE)
if (turboSwizzled(info->out_color_space)) {
ASSERT(!m_scaled);
while (info->output_scanline < info->output_height) {
unsigned char* row = reinterpret_cast<unsigned char*>(buffer.getAddr(0, info->output_scanline));
if (jpeg_read_scanlines(info, &row, 1) != 1)
return false;
#if USE(QCMSLIB)
if (qcms_transform* transform = m_reader->colorTransform())
qcms_transform_data_type(transform, row, row, info->output_width, rgbOutputColorSpace() == JCS_EXT_BGRA ? QCMS_OUTPUT_BGRX : QCMS_OUTPUT_RGBX);
#endif
}
return true;
}
#endif
JSAMPARRAY samples = m_reader->samples();
while (info->output_scanline < info->output_height) {
// jpeg_read_scanlines will increase the scanline counter, so we
// save the scanline before calling it.
int sourceY = info->output_scanline;
/* Request one scanline. Returns 0 or 1 scanlines. */
if (jpeg_read_scanlines(info, samples, 1) != 1)
return false;
int destY = scaledY(sourceY);
if (destY < 0)
continue;
#if USE(QCMSLIB)
if (m_reader->colorTransform() && info->out_color_space == JCS_RGB)
qcms_transform_data(m_reader->colorTransform(), *samples, *samples, info->output_width);
#endif
int width = m_scaled ? m_scaledColumns.size() : info->output_width;
for (int x = 0; x < width; ++x) {
JSAMPLE* jsample = *samples + (m_scaled ? m_scaledColumns[x] : x) * ((info->out_color_space == JCS_RGB) ? 3 : 4);
if (info->out_color_space == JCS_RGB)
buffer.setRGBA(x, destY, jsample[0], jsample[1], jsample[2], 0xFF);
#if defined(TURBO_JPEG_RGB_SWIZZLE)
else if (info->out_color_space == JCS_EXT_RGBA)
buffer.setRGBA(x, destY, jsample[0], jsample[1], jsample[2], 0xFF);
else if (info->out_color_space == JCS_EXT_BGRA)
buffer.setRGBA(x, destY, jsample[2], jsample[1], jsample[0], 0xFF);
#endif
else if (info->out_color_space == JCS_CMYK) {
// Source is 'Inverted CMYK', output is RGB.
// See: http://www.easyrgb.com/math.php?MATH=M12#text12
// Or: http://www.ilkeratalay.com/colorspacesfaq.php#rgb
// From CMYK to CMY:
// X = X * (1 - K ) + K [for X = C, M, or Y]
// Thus, from Inverted CMYK to CMY is:
// X = (1-iX) * (1 - (1-iK)) + (1-iK) => 1 - iX*iK
// From CMY (0..1) to RGB (0..1):
// R = 1 - C => 1 - (1 - iC*iK) => iC*iK [G and B similar]
unsigned k = jsample[3];
buffer.setRGBA(x, destY, jsample[0] * k / 255, jsample[1] * k / 255, jsample[2] * k / 255, 0xFF);
} else {
ASSERT_NOT_REACHED();
return setFailed();
}
}
}
return true;
}
