[FFmpeg-devel] [PATCH] mp4a-latm rtp output & dynamic payload type from URL

[Luca Abeni]

On Fri, 2009-10-09 at 18:13 +0300, Sergiy wrote:
[...]
> > However, I think your patch mixes too many changes together, and it 
> > should
> > be split in various parts. I am also not convinced that all the 
> > modifications
> > to avio.*, etc are really needed...
> I agree, but by default ffmpeg sets "96" dynamic rtp payload type, even 
> when multiple streams exists (but dynamic payload have to be unique for 
> every stream: 96, 97, ...). That's why payload _type parameter was added.
Yes, I agree that this feature is important and needed... We just need
to find a good way to implement it, without touching unrelated files
such as avio.c, etc...

[...]
> > According to the RFC (Section 4.1), it seems that the LATM
> > stream is directly copied in the packet payload, without
> > any payload-specific header... 
> We sending AudioMuxElement that consists from PayloadLengthInfo and 
> PayloadMux
> (as described in ISO/IEC 14496-3:2005)
> In this code latmhdrsize - is size in bytes of PayloadLengthInfo element.
I see... So, the muxer is receiving the AAC stream in non-LATM syntax,
and is adding a header to transform it in LATM? If this is the case, I
think we need to check if there is a simpler way to implement this
feature (maybe a bitstream filter?). Does ffmpeg support LATM? If yes,
how is it handled?
I'll try to have a look at the ISO/IEC standard to better understand
this stuff... 

I am going out for the weekend; I'll work on the above issues in next
week.


			Thanks,
				Luca