[Live-devel] rtspTestClient consumes the first bytes of each packet? How to prevent?

[Chris Paucar]

Apologies, I was recalling that statement from some old reading material.

And yes several of my cameras send a copy of both before every GOP so I
filter them out through a subclass of H264VideoRTPSource and I create my
own copies through the SDP description when I need them.

The reason I filter them out is because QuickTimeFileSink will write them
into the file and certain media players will incorrectly parse them as
video frames causing a stuttering effect.

Thanks,
Chris

On Thu, May 30, 2019 at 5:55 PM Ross Finlayson <finlayson at live555.com>
wrote:

>
>
> > On May 30, 2019, at 2:30 PM, Chris Paucar <chris.paucar at roc-connect.com>
> wrote:
> >
> > Hi Eric,
> >
> > Regarding #3, those are the SPS and PPS NAL units, size 22 and 4
> respectively. You can confirm by looking at the 5 lower bits of the first
> byte and matching the NAL unit type with values 7 and 8 for SPS and PPS.
> >
> > Some RTSP sources provide them in a separate stream
>
> This is not quite correct.  The SPS and PPS NAL units are encoded in the
> stream’s SDP description (which RTSP retrieves in response to its
> “DESCRIBE” command, before starting the actual streaming).  This is not “a
> separate stream” - it’s just a part of the stream’s (static) description,
> which RTSP retrieves at the beginning of the protocol exchange.
>
> These NAL units *may* (or may not) also appear (either only at the start,
> or periodically) inside the RTP video stream.  In Eric’s case, it appears
> that they do appear in the stream.  This is not necessary, however, because
> they (as noted above) are also coded in the stream’s SDP description.
>
>
> Ross Finlayson
> Live Networks, Inc.
> http://www.live555.com/
>
>
> _______________________________________________
> live-devel mailing list
> live-devel at lists.live555.com
> http://lists.live555.com/mailman/listinfo/live-devel
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.live555.com/pipermail/live-devel/attachments/20190530/a95db8ec/attachment-0001.htm>