[Asterisk-video] H324M AMR audio working!!!

[Sergio Garcia Murillo]

Hi Ratmin,  it's good to see you're alive and well...

> From: Ramtin Amin
> Sent: Thursday, March 01, 2007 3:48 PM
>
> The problem with bridging to SIP is bigger than you think
>
> My H324m stack is directly implemented into chan_zap, so I can place 3G
call with dial(zap/gv1/number) or I receive video call from a cellphone in
H263 mode.

Good, and what it's the difference bridging the call to a sip channel?
Beside of that sepparating the stack from zap allows the use of other kind
of channels, like misdn as matteo did..

> Also since I wrote codec_amr and format_amr, i gave chan_zap the amr
capability so the call is transcoded.

Writting a codec_amr and format_amr would allow every channel to be able to
transcode them.
By the way, do you have them avaiable? Where can i donwload them? How can i
use your library with chan zap?

> Currently when I bridge to SIP it works but there is a BIG problem, it's
the FPS that the softphone is sending.
> Basically, if the H263 video coded by the softphone is about 50kb/s its
fine. but if it's bigger (which is usually the case) then you loose frame.
> Also, the softphone is not usually capable of sending a SIP info as Video
Fast Update asking the softphone to reencode an I-frame.
> That's why I'm currenty working on the transcoding of H263 <> H263.

Yes, you're rigth, most videophones doesn't allow you to adjust the bandwith
it's send, and if they send you more it wont work.
Transcoding can be done in to ways, the good one and the easy one. The easy
one is just use an h263 decoder and a h263 encoder, the good one,
as somone pointed in the past, would be reuse the motion vectors and some
other data from the decoder so the encoder doesn't need to calculate them
again. Which one are u implementing? And once again, where can i download
it?

Greetings
Sergio García
http://sip.fontventa.com