[FFmpeg-devel] [PATCH] RTP depacketizer for QCELP

Martin Storsjö martin
Mon Nov 29 17:15:21 CET 2010

Hi Ronald,

On Mon, 29 Nov 2010, Ronald S. Bultje wrote:

> On Mon, Nov 29, 2010 at 4:24 AM, Martin Storsj? <martin at martin.st> wrote:
> [..]
> 2 and 3 are fine, can be applied anytime.

Applied these two

> 4 duplicates code, I think, can you somehow extract that?

Ok, I'll try to clean this up a bit.

> The depacketizer itself looks good on a first view but I want to look at 
> it a little more.

Good, I'll await further comments.

> I always thought that this worked already, as long as the
> "x-Purevoice" string was in the SDP. Is the new code required for the
> case were we use a static ID without the string (just "12")?

Yes, it worked if the x-Purevoice string was in the rtpmap field in the 
SDP. QuickTime doesn't add any rtpmap field at all for these, just the 
plain payload type 12 - you generally don't need any rtpmap field for the 
statically allocated payload types from standards.

> > +                    /* 0 actually is a valid static payload id, but that one
> > +                     * (PCMU) doesn't require a custom depacketizer */
> That's a little hacky... Should at least be documented in the struct...

Yeah, it's a bit hacky, but still doesn't really compromise anything since 
we probably never will need to map that codec to a dynamic depacketizer. 
I'll add a comment in the struct.

// Martin

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