[FFmpeg-devel] [PATCHv2 5/5] vorbis: extract metadata from the middle of a stream

Ben Boeckel mathstuf at gmail.com
Sun Oct 27 17:22:19 CET 2013

On Sun, 27 Oct, 2013 at 15:42:17 GMT, wm4 wrote:
> Or maybe public? Also maybe "dictionary" instead of "metadata", but not
> sure.
> If users are supposed to read the side data, an unpack function should
> be public as well, IMO.

I had meant to say [un]pack_metadata, so yes, an unpack would come as
well. Public would make sense for unpack at least. Is it expected that
codecs are written externally to ffmpeg? If not, pack might make sense
as a private function.

> If a single tag is removed (and there are others), the application gets
> an update, but if _all_ tags are removed, then not.

I guess an empty side_data message could be sent.

> In general, it would be strange if some file formats put metadata into
> side data, and some don't.

Well, AFAICT, they don't put it anywhere (where does ICY Info come
from?), so as long as any other codecs growing this functionality use
the same mechanism, it should be fine.

> I mean: it can't be handled in a codec independent way? (Maybe OGG is
> too horrible? I don't know much about OGG.)

Once the pack_metadata function is there, the code for each codec is
probably pretty small ("just" call into the metadata decoding done at
the start of the stream).


More information about the ffmpeg-devel mailing list