函数 av_write_uncoded_frame_query 

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

Test whether a muxer supports uncoded frame.

@return >=0 if an uncoded frame can be written to that muxer and stream, <0 if not