Quoting Alexander Strasser via ffmpeg-devel (2024-10-15 21:16:28) > On 2024-10-15 15:09 +0200, Anton Khirnov wrote: > > Quoting James Almer (2024-10-15 14:54:08) > > > On 10/15/2024 6:57 AM, Anton Khirnov wrote: > > > > avfilter_process_command() may or may not return ENOSYS whether that > > > > flag is set or not, so I don't see what exactly would it be useful for. > > > > > > I see, although I wouldn't expect ENOSYS for any other case than > > > "unsupported". If a command fails, imo it would be EINVAL, or maybe > > > ENOMEM. > > > > Correct, but > > * some commands work on all filters; for now it's just "ping", but we > > can add more in the future; > > * the "enable" command works on all filters flagged with > > AVFILTER_FLAG_SUPPORT_TIMELINE; again, we may add more such > > "semi-generic" commands in the future; > > * filters that do implement the process_command() callback will still > > return ENOSYS when you send them a command they do not support. > > > > So checking for the existence of process_command() does not really tell > > you anything specific, and the same would hold for the hypothetical flag > > that would replace it. > > > > > > > > > Same holds for printing the capability in fftools - just what is the > > > > user expected to do with that information? > > > > > > Know they can use the send command interrupt for a given filter without > > > having it unconditionally fail, i guess. But for that matter, is the > > > list of supported commands available anywhere for the user? Is there an > > > API to query them, or is it expected to be only in the documentation? > > > If there's no API, then maybe printing this is pointless. > > > > There is no such API, which I agree would be useful - but if it did > > exist we would again not need the flag. > > For me that flag is more about if some filter brings commands of its own.
Most filters implementing the process_command() callback just use the generic implementation - ff_filter_process_command(). So what information does that flag actually give you? -- Anton Khirnov _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
