Video decoding only. Certain video codecs support cropping, meaning that
only a sub-rectangle of the decoded frame is intended for display. This
option controls how cropping is handled by libavcodec.
When set to 1 (the default), libavcodec will apply cropping internally.
I.e. it will modify the output frame width/height fields and offset the
data pointers (only by as much as possible while preserving alignment, or
by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
the frames output by the decoder refer only to the cropped area. The
crop_* fields of the output frames will be zero.
When set to 0, the width/height fields of the output frames will be set
to the coded dimensions and the crop_* fields will describe the cropping
rectangle. Applying the cropping is left to the caller.
@warning When hardware acceleration with opaque output frames is used,
libavcodec is unable to apply cropping from the top/left border.
@note when this option is set to zero, the width/height fields of the
AVCodecContext and output AVFrames have different meanings. The codec
context fields store display dimensions (with the coded dimensions in
coded_width/height), while the frame fields store the coded dimensions
(with the display dimensions being determined by the crop_* fields).
Video decoding only. Certain video codecs support cropping, meaning that only a sub-rectangle of the decoded frame is intended for display. This option controls how cropping is handled by libavcodec.
When set to 1 (the default), libavcodec will apply cropping internally. I.e. it will modify the output frame width/height fields and offset the data pointers (only by as much as possible while preserving alignment, or by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that the frames output by the decoder refer only to the cropped area. The crop_* fields of the output frames will be zero.
When set to 0, the width/height fields of the output frames will be set to the coded dimensions and the crop_* fields will describe the cropping rectangle. Applying the cropping is left to the caller.
@warning When hardware acceleration with opaque output frames is used, libavcodec is unable to apply cropping from the top/left border.
@note when this option is set to zero, the width/height fields of the AVCodecContext and output AVFrames have different meanings. The codec context fields store display dimensions (with the coded dimensions in coded_width/height), while the frame fields store the coded dimensions (with the display dimensions being determined by the crop_* fields).