[asterisk-dev] Hi all, is struct ast_frame encoded by any codec?

[John Wu]

thank you all !

On Fri, Sep 10, 2010 at 5:55 AM, Russell Bryant <russell at digium.com> wrote:

>
> On Thu, 2010-09-09 at 15:21 -0500, Tilghman Lesher wrote:
> > On Thursday 09 September 2010 04:51:43 John Wu wrote:
> > > Is struct ast_frame transfer in asterisk channel just the rtp frame my
> > > application send out?
> >
> > No, the data portion of the ast_frame may be the rtp frame, though.
>  There's
> > an additional 'offset' element within the frame that points to the audio
> data
> > within whatever structure 'data' points to, and there's additional
> information
> > about the audio codec within ast_frame.  The point of all this is to make
> > ast_frame extremely efficient as a method of carting audio around within
> > Asterisk.
>
> Even if some RTP headers may be there, no code outside of the RTP system
> should assume that or try to touch that part of the buffer.  That would
> be evil (and extremely error prone).
>
> The key point here is that ast_frame is a generic structure inside of
> Asterisk used to carry signaling and media information.  It has nothing
> to do with RTP frames.
>
>
> --
> Russell Bryant
> Digium, Inc.  |  Engineering Manager, Open Source Software
> 445 Jan Davis Drive NW   -    Huntsville, AL 35806  -  USA
> jabber: rbryant at digium.com    -=-    skype: russell-bryant
> www.digium.com -=- www.asterisk.org -=- blogs.asterisk.org
>
>
>
>
>
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