[Live-devel] RTSP video decoding - packets too small

[Guillaume Ferry]

Hi Ross,

I just wanted to keep you in touch about my issue, and I'm glad to say 
it's now solved.
In fact, ffmpeg libraries already contain some useful parsers, and I 
especially use the 'av_parser_parse' method, which simply reads an input 
buffer and rebuilds a proper output frame.
Once a frame is complete, you just have to decode it using traditional 
methods, and everything rolls on.

Don't know if you're interested in those news though, but it might be 
useful if some liveMedia users want to do the same as me :)

Best regards,
Guillaume.

Le 07/09/2010 08:47, Ross Finlayson a écrit :
>> This video has (on purpose) no audio track, so I can focus on video 
>> stream only.
>> Payload of value 32 is an MPEG1 or MPEG2 video
>
> That's correct.
>
> An important thing to note about the RTP payload format for MPEG-1 or 
> MPEG-2 video (defined in RFC 2250) is that the data units delivered by 
> RTP are not (necessarily) complete video frames (even though our code 
> refers to them as 'frames' - which is admittedly a bit confusing).  
> For MPEG-1 or 2 video, the data units delivered by RTP - i.e., 
> delivered one-at-a-time by a "MPEG1or2VideoRTPSource" object - can be 
> MPEG headers, or one or more video 'slices', but need not be a 
> complete video frame.  (See RFC 2250 section 3.1 and Appendix 1.) This 
> allows a decoder to handle data loss without necessarily discarding an 
> entire video frame, but also means that it has to be a little smarter 
> about properly detecting when it has received enough data to make up 
> an entire frame.


-- 
Guillaume FERRY
Bertin Technologies
Département Bertin Conseil
Activité Traitement de l'Information et du Contenu
/Tél/ 	01.39.30.62.09
/Fax/ 	01.39.30.62.45
/Mail/ 	ferry at bertin.fr
/Web/ 	www.bertin.fr <http://www.bertin.fr>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.live555.com/pipermail/live-devel/attachments/20100913/5c382a1f/attachment.html>