Function ffmpeg_dev::sys::ff_add_format

pub unsafe extern "C" fn ff_add_format(
    avff: *mut *mut AVFilterFormats, 
    fmt: i64
) -> c_int

Add fmt to the list of media formats contained in *avff. If *avff is NULL the function allocates the filter formats struct and puts its pointer in *avff.

@return a non negative value in case of success, or a negative value corresponding to an AVERROR code in case of error