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();
}
void WEBPImageDecoder::applyPostProcessing(size_t frameIndex)
{
ImageFrame& buffer = m_frameBufferCache[frameIndex];
int width;
int decodedHeight;
if (!WebPIDecGetRGB(m_decoder, &decodedHeight, &width, 0, 0))
return; // See also https://bugs.webkit.org/show_bug.cgi?id=74062
if (decodedHeight <= 0)
return;
const IntRect& frameRect = buffer.originalFrameRect();
ASSERT_WITH_SECURITY_IMPLICATION(width == frameRect.width());
ASSERT_WITH_SECURITY_IMPLICATION(decodedHeight <= frameRect.height());
const int left = frameRect.x();
const int top = frameRect.y();
#if USE(QCMSLIB)
if (qcms_transform* transform = colorTransform()) {
for (int y = m_decodedHeight; y < decodedHeight; ++y) {
const int canvasY = top + y;
uint8_t* row = reinterpret_cast<uint8_t*>(buffer.getAddr(left, canvasY));
qcms_transform_data_type(transform, row, row, width, QCMS_OUTPUT_RGBX);
uint8_t* pixel = row;
for (int x = 0; x < width; ++x, pixel += 4) {
const int canvasX = left + x;
buffer.setRGBA(canvasX, canvasY, pixel[0], pixel[1], pixel[2], pixel[3]);
}
}
}
#endif // USE(QCMSLIB)
// During the decoding of current frame, we may have set some pixels to be transparent (i.e. alpha < 255).
// However, the value of each of these pixels should have been determined by blending it against the value
// of that pixel in the previous frame if alpha blend source was 'BlendAtopPreviousFrame'. So, we correct these
// pixels based on disposal method of the previous frame and the previous frame buffer.
// FIXME: This could be avoided if libwebp decoder had an API that used the previous required frame
// to do the alpha-blending by itself.
if ((m_formatFlags & ANIMATION_FLAG) && frameIndex && buffer.alphaBlendSource() == ImageFrame::BlendAtopPreviousFrame && buffer.requiredPreviousFrameIndex() != kNotFound) {
ImageFrame& prevBuffer = m_frameBufferCache[frameIndex - 1];
ASSERT(prevBuffer.status() == ImageFrame::FrameComplete);
ImageFrame::DisposalMethod prevDisposalMethod = prevBuffer.disposalMethod();
if (prevDisposalMethod == ImageFrame::DisposeKeep) { // Blend transparent pixels with pixels in previous canvas.
for (int y = m_decodedHeight; y < decodedHeight; ++y) {
m_blendFunction(buffer, prevBuffer, top + y, left, width);
}
} else if (prevDisposalMethod == ImageFrame::DisposeOverwriteBgcolor) {
const IntRect& prevRect = prevBuffer.originalFrameRect();
// We need to blend a transparent pixel with its value just after initFrame() call. That is:
// * Blend with fully transparent pixel if it belongs to prevRect <-- This is a no-op.
// * Blend with the pixel in the previous canvas otherwise <-- Needs alpha-blending.
for (int y = m_decodedHeight; y < decodedHeight; ++y) {
int canvasY = top + y;
int left1, width1, left2, width2;
findBlendRangeAtRow(frameRect, prevRect, canvasY, left1, width1, left2, width2);
if (width1 > 0)
m_blendFunction(buffer, prevBuffer, canvasY, left1, width1);
if (width2 > 0)
m_blendFunction(buffer, prevBuffer, canvasY, left2, width2);
}
}
}
m_decodedHeight = decodedHeight;
buffer.setPixelsChanged(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;
}
