[FFmpeg-devel] [PATCH] Parse DEFINESOUND tags in swf (fix ticket 1638)

[Michael Bradshaw]

On Tue, Oct 9, 2012 at 1:57 PM, Michael Niedermayer <michaelni at gmx.at>wrote:

> On Tue, Oct 09, 2012 at 10:34:34AM -0600, Michael Bradshaw wrote:
> > +            ast->time_base.num = 1;
> > +            ast->time_base.den = ast->codec->sample_rate;
>
> these 2 should be redundant
>
 Ah, thanks, I'll send an updated patch in a bit.

> +            ast->duration = avio_rl32(pb); // number of samples
> > +            if (((v>>4) & 15) == 2) { // MP3 sound data record
> > +                ast->skip_samples = avio_rl16(pb);
> > +                len -= 2;
> > +            }
> > +            len -= 7;
>
> > +            if ((res = av_get_packet(pb, pkt, len)) < 0)
> > +                return res;
>
> can this chunk be big ? i mean 100mb or so ?
> if this happens in realworld files its probably better to split in
> some fixed size packets to reduce memory need and latency until its
> fully loaded
>
 Technically, yeah, it could be big. The entire sound file is stored as a
single chunk. This was my main worry. In practice, they aren't that big,
seeing as they're typically shorter audio clips loaded onto the stage, but
it's possible someone could do that. I saw your comment on the ticket and
wanted to put together a working patch, at least, because adding that
(which I think is a good idea in the end) would require some logic changes
to the demuxer I believe, and I don't have a lot of time to figure out how
to nicely fit it all together.

Thanks

--Michael