The latency messages you see are totally unrelated.
One option is to use the raw YUV input instead of the MPEG input.
That's near instantaneous (I think).
I can't think how they would make mpeg encoding instantaneous in windows
since mpeg encoding relies on a history. Perhaps you can play with the
number of B frames (ivtvctl -c bframes=0) so no history is needed. If
the firmware is really smart, then it might have a lower latency.
Hans
On Wednesday 15 March 2006 22:00, Ola Theander wrote:
> Dear subscribers
>
> I'm right now trying out the Hauppauge PVR 150 card for use in a
> project where I need to capture composite video basically in real
> time. The video signal is received by the computer from a manually
> operated camera. The camera is mounted on a long cable which the
> computer operator guides in narrow pipes by the view on the computer
> screen. To make the operation as easy as possible for the operator I
> want as short delay as possible between actually moving the camera
> and until the movement is reflected on the computer screen.
>
> I realize that this isn't important if you e.g. capture a video from
> an analogue video camera since the delay when the video stream passes
> through the hardware/software until it's stored on the hard disk
> isn't noticeable when you later playback the video.
>
> I know that the Hauppauge card is capable of virtually no latency
> since I started out by trying it using Windows and on Windows the
> screen update when moving the camera was more or less instantaneous,
> at least the delay wasn't noticeable.
>
> The basic tests I've performed I just did "mplayer /dev/video0" and
> moved the camera. The delay seems to be in the order of 0.5 - 1.0
> seconds before the picture is updated. If I look in the output of
> dmesg I notice one line stating "ivtv0: Unreasonably low latency
> timer, setting to 64 (was 32)" and I wonder if that might have
> something to do with this?
>
> Eventually I'll use GStreamer instead and I know that the latency in
> the 0.8 code branch is much worse that it is in the latter 0.9 and
> 0.10. I've tried my solution with GStreamer 0.10 and an external
> composite 2 firewire-dv converter so I know that it's possible to
> have quite a low delay. Now I just hope that I can do the same using
> the PVR 150.
>
> Any help on this matter would be greatly appreciated.
>
> Kind regards, Ola Theander
>
>
> _______________________________________________
> ivtv-users mailing list
> [email protected]
> http://ivtvdriver.org/mailman/listinfo/ivtv-users
_______________________________________________
ivtv-users mailing list
[email protected]
http://ivtvdriver.org/mailman/listinfo/ivtv-users
