some codecs need / can use extradata like Huffman tables.
mjpeg: Huffman tables
rv10: additional flags
mpeg4: global headers (they can be in the bitstream or here)
The allocated memory should be FF_INPUT_BUFFER_PADDING_SIZE bytes larger
than extradata_size to avoid problems if it is read with the bitstream reader.
The bytewise contents of extradata must not depend on the architecture or CPU endianness.
- encoding: Set/allocated/freed by libavcodec.
- decoding: Set/allocated/freed by user.
some codecs need / can use extradata like Huffman tables. mjpeg: Huffman tables rv10: additional flags mpeg4: global headers (they can be in the bitstream or here) The allocated memory should be FF_INPUT_BUFFER_PADDING_SIZE bytes larger than extradata_size to avoid problems if it is read with the bitstream reader. The bytewise contents of extradata must not depend on the architecture or CPU endianness. - encoding: Set/allocated/freed by libavcodec. - decoding: Set/allocated/freed by user.