[FFmpeg-devel] [PATCH] Metadata

[Ronald S. Bultje]

Hi,

On Fri, Jan 2, 2009 at 6:55 PM, Michael Niedermayer <michaelni at gmx.at> wrote:
> Attached patch adds generic metadata support to
> ffmpeg.c, and the avi muxer and demuxer
> The implementation should be pretty much as simple as possible.
>
> Differences to aurels variant
> * flat metadata, no trees
> * fully abstracted, implementation can be changed with no effect on ABI/API
> * only a small set of muxers & demuxers are updated yet.
>
> Comments welcome, especally from aurel.

Please predefine common tags, to prevent "artist" vs. "Artist" or
"Title" vs. "Name" confusion, i.e. a few

#define AV_TAG_ARTIST "Artist"

would help in getting the basics right. More could be added as-we-go
and they would serve as a descriptive template (ideally with doxy
comments) of what the comment represents, which muxers implement it
(or maybe that's too much, don't know), etc. It probably sounds weird
at first sight, but if you go into Matroska tags with iso-language
codes for tracks etc., it helps to have a few lines of doxy code
explaining what it is so you can represent it to the user in a useful
manner rather than just "isoXYZ code: eng".

/** ISO-XYZ language code, represents the language in which this track
is performed */
#define AV_TAG_ISOXYZ "iso-xyz"

And of course it's a nice list of all tags supported by the cumulative
set of demuxers.

Ronald