The VideoLAN Forums

Hello,

Hopefully someone else has worked though this issue with their VLC + WintTV PVR card setup. I'm trying to stream a live video feed with VLC, that is being captured and encoded with a WinTV PVR 350 card. The picture quality on the receiving side looks great, the only problem is the latency; almost 2.5 to 3 seconds between when an event occurs to when the video is displayed on the receiving side. I've decreased the various UDP buffers as described in other posts, but I can't seem to get it any lower. From what I can tell, the lag seems to be on the encoding end. Any ideas about how to get the latency down to the 500ms end-to-end time that others have reported?
The encoder box is running Linux with VLC 0.7.2.

Thanks,
Static

Are you sure it's not because you are using a software decoder on the recieving side?

If you have any control of the card, switch it to raw mode (no compression), and do the encoding in the host PC. If your host is "decent", then you'll get the 700 ms range.

If you ever want a laugh, try watching a professional sports game on TV, while listening to the radio. You would think the radio sports people are psychic, calling the outcome of shots before you see them on TV

As per the decoder on the recieving side, I'm directing the output of the video to the decoder card. Basically, I write the incoming video stream to /dev/video16.

As for getting raw output from the encoder, VLC can't seem to understand the raw YUV that the PVR-250 puts out. Does any one know of a way to get VLC to understand the raw YUV.

I was just thinking, another possibility might be to decrease the (hardware) encoder buffer size. Does anyone know if vlc can pass an argument to IVTV to do that?

You might want to try the latest 0.8 test2 nightly build, for the TX (server) VLC. Gibalou has been working various things relative to chroma, so perhaps it'll now work with your PVR's YUV raw output format. (No guarantee, just a thought).

your messages here are very helpful. I didnot get the sound first but after reading these discussion, I got both the sound and picture! thank you for all this great help!