[Asterisk-video] RE: [asterisk-dev] H.263 Buffer size

[Sergio García Murillo]

Tilghman Lesher wrote:
> On Tuesday 18 July 2006 01:29, Sergio García Murillo wrote:
>> John Martin wrote:
>>> Hi Devs,

> I'm not so sure that downgrading the quality of the frame is even
> within the purview of a format_ module.  If Asterisk is acting as a
> temporary storage location for an image that the user has decided
> that it needs to be a particular sample size, then a decision on
> frame size has already been made by the operator, and Asterisk SHOULD
> NOT override that decision.     

IMHO it's not that easy. Working with h263 and rtp means that you have to follow
some  rules for rtp packetization (rfc 2190 or 2490). They must containt full gobs/slices
in each packet and you must add some payload information (motion vectors, 
gob number, picture type) in it. 

So there is BIG problem if you plan to send an h263 stream from a non rtp source 
(H324M or H320 as it has been discussed in the video list) to a rtp one, because
you at least would need to parse the h263 to find the gob boundaries and calculate the
rest of the parameters for the header.

And if you'r bridging two rtp streams I still haven't seen any that uses packets
over 1500 bytes. 
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