[FFmpeg-devel] [PATCH] use new metadata API in mov (de)muxer

[Aurelien Jacobs]

Baptiste Coudurier wrote:

> Hi,
> 
> On 2/12/2009 2:06 PM, Aurelien Jacobs wrote:
> >>>
> >>> -    case MKTAG(0xa9,'n','a','m'):
> >>> -        str = c->fc->title; size = sizeof(c->fc->title); break;
> >>> +    case MKTAG(0xa9,'n','a','m'): key = "title";     break;
> >>> +    case MKTAG(0xa9,'a','u','t'):
> >>>      case MKTAG(0xa9,'A','R','T'):
> >>> -    case MKTAG(0xa9,'w','r','t'):
> >>> -        str = c->fc->author; size = sizeof(c->fc->author); break;
> >>> -    case MKTAG(0xa9,'c','p','y'):
> >>> -        str = c->fc->copyright; size = sizeof(c->fc->copyright); break;
> >>> +    case MKTAG(0xa9,'w','r','t'): key = "author";    break;
> >>> +    case MKTAG(0xa9,'c','p','y'): key = "copyright"; break;
> >>>      case MKTAG(0xa9,'c','m','t'):
> >>> -    case MKTAG(0xa9,'i','n','f'):
> >>> -        str = c->fc->comment; size = sizeof(c->fc->comment); break;
> >>> -    case MKTAG(0xa9,'a','l','b'):
> >>> -        str = c->fc->album; size = sizeof(c->fc->album); break;
> >>> +    case MKTAG(0xa9,'i','n','f'): key = "comment";   break;
> >>> +    case MKTAG(0xa9,'a','l','b'): key = "album";     break;
> >>> +    case MKTAG(0xa9,'d','a','y'): key = "year";      break;
> >>> +    case MKTAG(0xa9,'g','e','n'): key = "genre";     break;
> >>> +    case MKTAG(0xa9,'t','o','o'):
> >>> +    case MKTAG(0xa9,'e','n','c'): key = "muxer";     break;
> >> I saw that in vorbis demuxer you exported metadata "as is", but here you
> >>  apply some generic metadata.
> >>
> >> 1) Shouldn't we also export "as is" everything in "udta" atom coded in a
> >> somewhat standard way (itunes, 3gp, mov) ? This is what I would call
> >> "generic" and user could retrieve it if wanted.
> > 
> > That would indeed be more generic, but from my understanding, the
> > metadata key is supposed to be a user understandable string. A end
> > user application should display the straight key string.
> > mov atom identifier don't really qualify as user readable string...
> 
> Yes, I agree, I proposed to export both actually.

I can't really imagine what would this be useful for ?
But if you think it has any use, the mov demuxer (or muxer ?) could export
a kind of conversion table with the list of atom corresponding to each of
the common key ("author", "album", etc...).
But this is not really related to the new metadata API. It could already
have been done with old API. And it seems it wasn't useful enough for
someone to implement it.

Aurel