[FFmpeg-devel] [RFC] TS/DVB subtitle sub_id hack

Baptiste Coudurier baptiste.coudurier
Mon Jul 12 08:11:31 CEST 2010

On 7/11/10 3:43 PM, Reimar D?ffinger wrote:
> On Sun, Jul 11, 2010 at 03:33:00PM -0700, Baptiste Coudurier wrote:
>> Even easier is to use codec_tag.
>> I don't think extradata is a good idea. It makes applications do if
>> codec_id == CODEC_ID_DVBSUB then set extradata which is more
>> complicated than setting sub_id even if it does not conform to the
>> documentation.
> How is if (codec_id == CODEC_ID_DVBSUB) {misuse codec_tag}
> significantly better?

At least, it avoids malloc.
Besides the anc value change it will be more complicated to handle,
since extradata is not supposed to change.

> And should all muxers then start to write those values as codec_tag?

How does any other format handle this, if any ?

> Or should then all have a special case for DVBSUB as well?
> I can't image misusing codec_tag as ending up as anything other
> than quite painful.

Like sub_id it is simpler, malloc is way more painful.

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