pub unsafe extern "C" fn ff_alloc_input_device_context(
avctx: *mut *mut AVFormatContext,
iformat: *mut AVInputFormat,
format: *const c_char,
) -> c_int
pub unsafe extern "C" fn ff_alloc_input_device_context(
avctx: *mut *mut AVFormatContext,
iformat: *mut AVInputFormat,
format: *const c_char,
) -> c_int