void add_output(const ImageFormat &format, OutputAlphaFormat alpha_format);
// Adds an YCbCr output. Note that you can only have one output.
// Currently, only chunked packed output is supported, and only 4:4:4
// (so chroma_subsampling_x and chroma_subsampling_y must both be 1).
void add_output(const ImageFormat &format, OutputAlphaFormat alpha_format);
// Adds an YCbCr output. Note that you can only have one output.
// Currently, only chunked packed output is supported, and only 4:4:4
// (so chroma_subsampling_x and chroma_subsampling_y must both be 1).