[Live-devel] Increasing video latency for RTSP client

[Jeff Shanab]

I work with 5Mp and larger streams a lot.
This is probably not a live555 issue but there are 2 things that come to
mind that the larger streams stress without using a lot of CPU.

Decoding not keeping up. (Buffers on client side, watch client memory to
see this.)
   Single threaded decoding can take more time to decode than the duration
between frames when they get large. This can happen even with less than 50%
of a single core.
   Reduce quality settings on stream,
   Reduce framerate.
   Reduce resolution.
   Skip most or all the decoding. printing out the framesize, timestamp and
type once every 60 keyframes or a keyframe only and see if it eliminates
the delay
   Recompile the the decoder to use multiple threads.

TCP vs UDP (Buffers on server side, usually delay->loss of framerate->skips
to catch back up->repeat.)
  Network delay impacts the required buffer on the camera side more if TCP
transport is chosen.
  It may have to resend so it hangs on until the ACK. If the buffer is
small and gets full the camera starts to drop frames.
  It also is just plain more work, try UDP transport.

On Mon, Nov 23, 2015 at 3:06 AM, Sergio Basurco <
sergio.b at coherentsynchro.com> wrote:

> Hello all,
>
> I'm trying to decode RTSP H264 streams, there is an IP camera that has 5MP
> frames. I used to have lots of decoding errors and this was due to the
> receive buffer size. Using the increaseReceiveBufferTo(...) function I
> managed to fix the decoding artifacts.
>
> Now however, I have an ever-increasing video delay, it starts small but
> keeps delaying over time. I don't know what could be causing this. The
> program does very little else so I don't think the computer cannot keep up.
>
> Is there something within Live555 that can cause/prevent such delays?
>
> Thank you,
>
> --
> Sergio Basurco,
> Coherent Synchro
>
> _______________________________________________
> live-devel mailing list
> live-devel at lists.live555.com
> http://lists.live555.com/mailman/listinfo/live-devel
>
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