Streaming Delay

[Nine]

I noticed that there is about a 2 second delay in streaming content.

I was thinking about using VLC as an alternate to VNC, as a way of having a thin client and a central server. That is on a dual or quad processor system, with VLC running and capturing the screen and streaming it, and the other processors doing media, 3d graphics, or games. Using Synergy (http://synergy2.sourceforge.net/) for mouse and keyboard.

I'm using VH Screen Capture driver, for the screen capture http://www.hmelyoff.com/.

In testing this out, I set up a UDP stream and I noticed a 2 second delay. It's not the capture device, if I open the capture device there is only a few frames lag. It's not my network, because I've tried it via local host (127.0.0.1). I tried different codecs for transcoding the stream, but there was no difference.

Any ideas what this is, is it transcoding or is it part of UDP or something else?

[yoann]

There is some caching when streaming in UDP with VLC that you could try to decrease. Have a look at the preferences there (with Advanced options checked off):
- Stream output -> Access output -> UDP (for your server)
- Input/Codecs -> Access modules -> UDP/RTP (for your client)

Default caching is 300ms for both of them, so you could theoretically save a 600ms delay with these settings...

[Nine]

Thanks!!! That definetly sped it up by 600ms! The delay was about 1900ms, now its about 1300ms. I wonder what the rest of the delay could be. I'll look at the other settings, see if there is anything obvious.

[Nine]

There is another thing I notice. For the DirectShow settings there is a delay that defaults to 200ms. If I set this to zero, then the display is more snappy (maybe down to the minimal 1 frame delay). This works fine when I simply view it in VLC, but if I stream it with this setting, the recieving client at some point stops updating. And it seems like 200ms is a magic number, everything below it eventually causes the client to stop updating.

[KevinFromCville]

Hello - I am very interested in the answer to this as well. I am trying to use two DV camcorders (WinXP, directshow) in a videoconferencing application. The video looks good but delayed by the afore-mentioned 2 seconds. Interestingly, under vlc 8.2 I could not get the video to stream at all unless I set the direct show caching value to 0. As Nine mentions, 8.5 seems to like a value of 200

[ama]

Hello

how can we set the same options using the comman line ?

thanks

[Myster]

The delay exists! I try to stream in HTTP and delay is 2 sec. It's not a UDP issue.
Please help!

Thank you.

[lagarazo]

There is some caching when streaming in UDP with VLC that you could try to decrease. Have a look at the preferences there (with Advanced options checked off):
- Stream output -> Access output -> UDP (for your server)
- Input/Codecs -> Access modules -> UDP/RTP (for your client)

Default caching is 300ms for both of them, so you could theoretically save a 600ms delay with these settings...

Are these settings related to any command parameters? What do we have to do in command line?

[DJ]

All command line functions (syntax) may be found by typing vlc -H on the command line in the VLC folder.

I believe you will find that by eliminating all the delays (buffering), streaming will be impossible! but you are most welcome to try.