Method copyImgToByteArray

YUViewLib/src/decoder/decoderDav1d.cpp:475–534

void decoderDav1d::copyImgToByteArray(const Dav1dPictureWrapper &src, byteArrayAligned &dst)
#else
void decoderDav1d::copyImgToByteArray(const Dav1dPictureWrapper &src, QByteArray &dst)
#endif
{
  // How many image planes are there?
  int nrPlanes = (src.getSubsampling() == Subsampling::YUV_400) ? 1 : 3;

  // At first get how many bytes we are going to write
  const auto nrBytesPerSample = (src.getBitDepth() > 8) ? 2 : 1;
  const auto framSize         = src.getFrameSize();
  auto       nrBytes          = frameSize.width * frameSize.height * nrBytesPerSample;
  auto       layout           = src.getSubsampling();
  if (layout == Subsampling::YUV_420)
    nrBytes += (frameSize.width / 2) * (frameSize.height / 2) * 2 * nrBytesPerSample;
  else if (layout == Subsampling::YUV_422)
    nrBytes += (frameSize.width / 2) * frameSize.height * 2 * nrBytesPerSample;
  else if (layout == Subsampling::YUV_444)
    nrBytes += frameSize.width * frameSize.height * 2 * nrBytesPerSample;

  DEBUG_DAV1D("decoderDav1d::copyImgToByteArray nrBytes %d", nrBytes);

  // Is the output big enough?
  if (dst.capacity() < int(nrBytes))
    dst.resize(int(nrBytes));

  uint8_t *dst_c = (uint8_t *)dst.data();

  // We can now copy from src to dst
  for (int c = 0; c < nrPlanes; c++)
  {
    auto width  = framSize.width;
    auto height = framSize.height;
    if (c != 0)
    {
      if (layout == Subsampling::YUV_420 || layout == Subsampling::YUV_422)
        width /= 2;
      if (layout == Subsampling::YUV_420)
        height /= 2;
    }
    const size_t widthInBytes = width * nrBytesPerSample;

    uint8_t *img_c = nullptr;
    if (decodeSignal == 0)
      img_c = curPicture.getData(c);
    else if (decodeSignal == 1)
      img_c = curPicture.getDataPrediction(c);
    else if (decodeSignal == 2)
      img_c = curPicture.getDataReconstructionPreFiltering(c);

    if (img_c == nullptr)
      return;

    const int stride = (c == 0) ? curPicture.getStride(0) : curPicture.getStride(1);
    for (size_t y = 0; y < height; y++)
    {
      memcpy(dst_c, img_c, widthInBytes);
      img_c += stride;
      dst_c += widthInBytes;
    }