bool WEBPImageDecoder::decodeSingleFrame(const uint8_t* dataBytes, size_t dataSize, size_t frameIndex)
{
if (failed())
return false;
ASSERT(isDecodedSizeAvailable());
ASSERT(m_frameBufferCache.size() > frameIndex);
ImageFrame& buffer = m_frameBufferCache[frameIndex];
ASSERT(buffer.status() != ImageFrame::FrameComplete);
if (buffer.status() == ImageFrame::FrameEmpty) {
if (!buffer.setSize(size().width(), size().height()))
return setFailed();
buffer.setStatus(ImageFrame::FramePartial);
// The buffer is transparent outside the decoded area while the image is loading.
// The correct value of 'hasAlpha' for the frame will be set when it is fully decoded.
buffer.setHasAlpha(true);
buffer.setOriginalFrameRect(IntRect(IntPoint(), size()));
}
const IntRect& frameRect = buffer.originalFrameRect();
if (!m_decoder) {
WEBP_CSP_MODE mode = outputMode(m_formatFlags & ALPHA_FLAG);
if (!m_premultiplyAlpha)
mode = outputMode(false);
#if USE(QCMSLIB)
if (colorTransform())
mode = MODE_RGBA; // Decode to RGBA for input to libqcms.
#endif
WebPInitDecBuffer(&m_decoderBuffer);
m_decoderBuffer.colorspace = mode;
m_decoderBuffer.u.RGBA.stride = size().width() * sizeof(ImageFrame::PixelData);
m_decoderBuffer.u.RGBA.size = m_decoderBuffer.u.RGBA.stride * frameRect.height();
m_decoderBuffer.is_external_memory = 1;
m_decoder = WebPINewDecoder(&m_decoderBuffer);
if (!m_decoder)
return setFailed();
}
m_decoderBuffer.u.RGBA.rgba = reinterpret_cast<uint8_t*>(buffer.getAddr(frameRect.x(), frameRect.y()));
switch (WebPIUpdate(m_decoder, dataBytes, dataSize)) {
case VP8_STATUS_OK:
applyPostProcessing(frameIndex);
buffer.setHasAlpha((m_formatFlags & ALPHA_FLAG) || m_frameBackgroundHasAlpha);
buffer.setStatus(ImageFrame::FrameComplete);
clearDecoder();
return true;
case VP8_STATUS_SUSPENDED:
if (!isAllDataReceived() && !frameIsCompleteAtIndex(frameIndex)) {
applyPostProcessing(frameIndex);
return false;
}
// FALLTHROUGH
default:
clear();
return setFailed();
}
}
void WEBPImageDecoder::clearFrameBuffer(size_t frameIndex)
{
if (m_demux && m_demuxState >= WEBP_DEMUX_PARSED_HEADER && m_frameBufferCache[frameIndex].status() == ImageFrame::FramePartial) {
// Clear the decoder state so that this partial frame can be decoded again when requested.
clearDecoder();
}
ImageDecoder::clearFrameBuffer(frameIndex);
}
void WEBPImageDecoder::clear()
{
#if USE(QCMSLIB)
clearColorTransform();
#endif
WebPDemuxDelete(m_demux);
m_demux = 0;
clearDecoder();
}
void WEBPImageDecoder::clear()
{
#if USE(QCMSLIB)
if (m_transform)
qcms_transform_release(m_transform);
m_transform = 0;
#endif
WebPDemuxDelete(m_demux);
m_demux = 0;
clearDecoder();
}
bool WEBPImageDecoder::decodeSingleFrame(const uint8_t* dataBytes,
size_t dataSize,
size_t frameIndex) {
if (failed())
return false;
ASSERT(isDecodedSizeAvailable());
ASSERT(m_frameBufferCache.size() > frameIndex);
ImageFrame& buffer = m_frameBufferCache[frameIndex];
ASSERT(buffer.getStatus() != ImageFrame::FrameComplete);
if (buffer.getStatus() == ImageFrame::FrameEmpty) {
if (!buffer.setSizeAndColorSpace(size().width(), size().height(),
colorSpace()))
return setFailed();
buffer.setStatus(ImageFrame::FramePartial);
// The buffer is transparent outside the decoded area while the image is
// loading. The correct alpha value for the frame will be set when it is
// fully decoded.
buffer.setHasAlpha(true);
buffer.setOriginalFrameRect(IntRect(IntPoint(), size()));
}
const IntRect& frameRect = buffer.originalFrameRect();
if (!m_decoder) {
WEBP_CSP_MODE mode = outputMode(m_formatFlags & ALPHA_FLAG);
if (!m_premultiplyAlpha)
mode = outputMode(false);
if (colorTransform()) {
// Swizzling between RGBA and BGRA is zero cost in a color transform.
// So when we have a color transform, we should decode to whatever is
// easiest for libwebp, and then let the color transform swizzle if
// necessary.
// Lossy webp is encoded as YUV (so RGBA and BGRA are the same cost).
// Lossless webp is encoded as BGRA. This means decoding to BGRA is
// either faster or the same cost as RGBA.
mode = MODE_BGRA;
}
WebPInitDecBuffer(&m_decoderBuffer);
m_decoderBuffer.colorspace = mode;
m_decoderBuffer.u.RGBA.stride =
size().width() * sizeof(ImageFrame::PixelData);
m_decoderBuffer.u.RGBA.size =
m_decoderBuffer.u.RGBA.stride * frameRect.height();
m_decoderBuffer.is_external_memory = 1;
m_decoder = WebPINewDecoder(&m_decoderBuffer);
if (!m_decoder)
return setFailed();
}
m_decoderBuffer.u.RGBA.rgba =
reinterpret_cast<uint8_t*>(buffer.getAddr(frameRect.x(), frameRect.y()));
switch (WebPIUpdate(m_decoder, dataBytes, dataSize)) {
case VP8_STATUS_OK:
applyPostProcessing(frameIndex);
buffer.setHasAlpha((m_formatFlags & ALPHA_FLAG) ||
m_frameBackgroundHasAlpha);
buffer.setStatus(ImageFrame::FrameComplete);
clearDecoder();
return true;
case VP8_STATUS_SUSPENDED:
if (!isAllDataReceived() && !frameIsCompleteAtIndex(frameIndex)) {
applyPostProcessing(frameIndex);
return false;
}
// FALLTHROUGH
default:
clear();
return setFailed();
}
}
void WEBPImageDecoder::clear() {
WebPDemuxDelete(m_demux);
m_demux = 0;
m_consolidatedData.reset();
clearDecoder();
}
