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

[Michael Bradshaw]

On Tue, Oct 9, 2012 at 8:32 PM, Michael Niedermayer <michaelni at gmx.at> wrote:
> On Tue, Oct 09, 2012 at 07:24:01PM -0600, Michael Bradshaw wrote:
>> 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.
>
> agree its better to support it this way than not at all but please add
> a FIXME comment or something that ideally this should be split into
> multiple packets

Ok, I've attached an updated patch. It might conflict a bit with
Clément's patch that adds the TAG_DEFINESOUND macro too.

Thanks,

Michael
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0001-Parse-DEFINESOUND-tags-in-swf-fix-ticket-1638.patch
Type: application/octet-stream
Size: 3065 bytes
Desc: not available
URL: <http://ffmpeg.org/pipermail/ffmpeg-devel/attachments/20121011/ae295504/attachment.obj>