函数 av_write_uncoded_frame 

pub unsafe extern "C" fn av_write_uncoded_frame(
    s: *mut AVFormatContext,
    stream_index: c_int,
    frame: *mut AVFrame,
) -> c_int

Write an uncoded frame to an output media file.

The frame must be correctly interleaved according to the container specification; if not, av_interleaved_write_uncoded_frame() must be used.

See av_interleaved_write_uncoded_frame() for details.