[FFmpeg-user] H263 support - looking for clarification

Marek Strejczek marek.strejczek at amg.net.pl
Thu Jul 14 15:31:58 CEST 2011

is H263 (RFC2190) encoding/decoding supported by FFmpeg when used with RTP?
I know that RFC2190 has historical status and RFC4629 should be used for 
carrying H263 over RTP, but my app happens to communicate with a 3rd 
party system that still uses RFC2190.

If I understand properly: H.263 (RFC2190) has corresponding RTP payload 
type 34 and H.263 (RFC4629) doesn't have static payload type assigned 
and can use one from dynamic range 96-127.
In rtp.c file I can see that even when using CODEC_ID_H263 the payload 
type 34 is never used, although AVRtpPayloadTypes associates PT 34 with  
CODEC_ID_H263. Also rtpdec_h263.c and rtpenc_h263.c files contain hints 
that only RFC4629 is supported.
That would indicate that RFC2190 is not supported in any way, am I correct?

Another question - can someone explain which H.263 RTP payloadings are 
handled by CODEC_ID_H263 and which by CODEC_ID_H263P?
There are 6 H.263-over-RTP combinations that I'm aware of:
H263 (RFC2190)
H263 (RFC4629)
H263+ (RFC2429)
H263+ (RFC4629)
H263++ (RFC2429)
H263++ (RFC4629)

I spent couple of hours googling for answers and analysing sources but 
got rather stuck, so I'll appreciate any clarification.

Best regards
Marek Strejczek

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