Minimal latency streaming with VLC

[markfm]

I'm trying to stream video, absolute minimum delay time from the input at a framegrabber to the output on the user screen. Video only, no audio.

I'm using a decent framegrabber, 640x480 resolution, VLC works nicely with it.

My network is deterministic, one hop over a router -- no worry about delays by packets taking different routes, or congestion introduced by other users.

I'm trying to get a feel for what parameters I might tweak to knock down the total delay time to a minimum.

My target total bandwidth is 1.2 megabits per second. I really don't want to go above that as the maximum, so that there is sufficient BW for the other payload the channel must sustain (things I control, but that do take bandwidth)

default_pts_delay is an obvious thing to adjust, I understand. What about
vdec_idle_sleep -- would adjusting that have any impact?

Any other variables that could be damped down, given I only care about video and have a "good" network connection?

Any area of the software that I could/should look at which I might tweak to keep the actual max BW down at my target? Right now, it looks like I need to subtract about 400 kbps due to BW spikes in VLC operation -- in other words now I have to set VLC video BW at 800 kbps to live within 1.2 Mbps (I monitor BW using Win2K's performance monitor, which is what's indicating the 400 kbps spikes periodically).

Should I be looking towards an H.264 encoder? Is H.264 implementation a bit faster than VLC's present MP4?

Thanks.

[Gibalou]

The latency is tweakable from the command line / preferences panel. No need to modify the source for that.

Of interest are all the --foo-caching config options. I guess for your needs, you'll have to use the --dshow-caching option on the server as well as the --sout-udp-caching (caching in the output layer).
On the client, you'll have to use the --udp-caching option.

If you are muxing everything in an MPEG transport stream, there is also a "mux=ts{caching=blabla}" option you can use (renamed to "shaping" instead of "caching" in cvs).

Have a look at this thread as well, I'm sure you'll find interesting things:
http://www.via.ecp.fr/via/ml/vlc-devel/ ... 00061.html

[markfm]

Super, thanks!