[asterisk-dev] AST_FRAME_DIGITAL

[Klaus Darilion]

Russell Bryant schrieb:
> I can tell you right now that you will not be able to convince me that we should
> add an opaque frame type for this situation.  It is completely against the
> Asterisk architecture.  As you said, the stream you are handling is in fact
> voice and video.  Asterisk has explicit handling for voice and video, and the
> streams should be passed into Asterisk using those frame types.

Hi Russel!

A simple scenario: A Asterisk server is used as PBX and is connected to 
the PSTN with a PRI (zap). Further, it has a BRI card to connect to 
in-house BRI devices.

Asterisk bridges calls between BRI and PRI, and sometimes this is a 
digital call. As digital calls do not have proper treating yet, it will 
happen that Asterisk thinks that PRI uses ulaw and BRI uses alaw and 
starts transcoding - which is a very bad thing for digital connections.

Thus, why do we have a AST_FRAME_IMAGE? Why is IMAGE not treated as 
VOICE? Obviously because Asterisk would transcode and the image is 
broken - the same reason why I like AST_FRAME_DIGITAL.

Maybe I do not need AST_FRAME_DIGITAL at all but could use 
AST_FRAME_IMAGE too - but I do not know how Asterisk handles images and 
maybe someday a feature is added to resize images and then it aagin 
would break digital connections.

Thus I think Asterisk should have a AST_FRAME_DIGITAL for bridging any 
data without interpretation.

regards
klaus