[FFmpeg-devel] Support of udta fields handled by libquicktime

[Michael Niedermayer]

On Fri, Jul 06, 2012 at 01:15:07PM +0000, al wrote:
> Hi,
> 
> I`ve been using the ffmpeg api to write out .mov`s with the prores encoder,
> internally we use libquicktime for our other movs.
> 
> It appears libquicktime uses different identifiers for various udta fields, this
> means if I try and set the comment field in ffmpeg when I generate the mov, it`s
> not visible to libquicktime.
> 
> This this intended or just missing functionality, I`m guessing the spec for this
> stuff is a bit flexible.
> 
> In movenc.c ffmpeg does the following:-
> 
>          } else if (mov->mode == MODE_MOV) { // the title field breaks gtkpod
> with mp4 and my suspicion is that stuff is not valid in mp4
>             mov_write_metadata(s, pb_buf, "\251ART", "artist");
>             mov_write_metadata(s, pb_buf, "\251nam", "title");
>             mov_write_metadata(s, pb_buf, "\251aut", "author");
>             mov_write_metadata(s, pb_buf, "\251alb", "album");
>             mov_write_metadata(s, pb_buf, "\251day", "date");
>             mov_write_metadata(s, pb_buf, "\251swr", "encoder");
>             mov_write_metadata(s, pb_buf, "\251des", "comment");
>             mov_write_metadata(s, pb_buf, "\251gen", "genre");
>             mov_write_metadata(s, pb_buf, "\251cpy", "copyright");
>         } else {
> 
> It seems libquicktime is looking for "\251cmt" for the comment field not 
> "\251des", I think quite a few of these fields don`t matchup.
> 
> Is support likely to be added to make this support libquicktime or am I best off
> patching my own copy to support this ?

best would be if you add the fields that are needed, check the mov
spec if the correct names are documented and if things really where
wrong or if there are 2 competing naming systems and once it all makes
sense and looks correct to you submit a patch with
references to the specs if any list these tags

I very much would like to have this fixed in ffmpeg!

thanks

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

If a bugfix only changes things apparently unrelated to the bug with no
further explanation, that is a good sign that the bugfix is wrong.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 198 bytes
Desc: Digital signature
URL: <http://ffmpeg.org/pipermail/ffmpeg-devel/attachments/20120706/9711726b/attachment.asc>