Video Stuttering -- Probelm Tied to Recording

[tweeknockr]

Hi,

So I just installed GB-PVR with my new HTPC. I’m running:

Athlon 3800+ Dual core
Windows XP MCE 2005
2 GB RAM
nVidia Geforce 7600 GS
vBox HDTV Tuner (ATSC Signal)
3.0 GB/s SATA Hard Drive

The problem I’m having is that every 30 seconds or so, the video playback will be very choppy for about 10 seconds, and then go back to normal.

I think I have eliminated the possibility of it being a decoding issue, as when I record something, the skipping will occur at the same point in the recording, regardless of what player I use to play it back with. (I'm currently using the Nvidia decoder, as it seemed to work best with my Nvidia graphics card).

This led me to the BDA mux options, which I tried many combinations of (CyberLink, DVR-MS), all of which yield pretty much the same results. I checked the version of the CyberLink it's using (top entry on BDA Mux Checker), and it's version 5.x....

This problem seems to occur all the time, including Live TV as well as when I record, and as I mentioned this problem is repeatable as the stuttering appears to be tied to the recording. I considered the possibility of a HDD error when writing, but running at 3.0 GB/s, I can’t imagine this would be the case.

I’ve zipped up and attached all of my log files.

Thanks for any help you can provide,

Josh

[sub]

Have you tried playing back the file on another machine? It could be sound card or an audio filter on your machine that is causing this.

[-stattik-]

Try dropping the video on mplayer. When all other apps stutter or fail, mplayer is usually able to play it cleanly.

[tweeknockr]

I just tried playing the file on another machine, and indeed it stutters at the exact same spot, which indicates it is indeed tied to the recording.

What could go wrong between the OTA signal and the dvr-ms file that could cause this stuttering?

Thanks,

Josh

[sub]

If its doing it with different muxes, then it sounds like some fault of your card.

[tweeknockr]

Hmm... when watching "Live TV" (no timeshift), is it doing any mpeg encoding? Or is it simply passing the signal from the capture card to the video card?

Thanks

[sub]

Sorry I dont have any suggestions for you.

The stream of data goes straight from your capture card, through the Microsoft MPEG Demultiplexer, then into the multiplexer your using (and saved to disk). I've not encountered bugs in the Microsoft MPEG Demultiplexer in the last two and half years, so I'm pretty sure the problem is either your card or the multiplexer. There isnt really anything you can tweak on either of these - they either do their job or they dont.

[tweeknockr]

Thought I'd just post an update... I updated my VBox's drivers, and everything works great now!

Thanks for all the help!

[fla]

I was getting almost the same behavior. Stuttering for 15 seconds once every 20-30 minutes on some channels more than others. The stuttering itself was cyclic (about 1/sec) which made me think it could be related to 2-3 insertion/3-2 pulldown. By changing the nvidia purevideo de-interlace control from automatic to smart the problem is gone. These settings are very well explained here.

http://www.anandtech.com/printarticle.aspx?i=2305

I wonder if the mpeg stream could have been flagged (23/30 fps) incorrectly causing the decoder to do the wrong thing? Are the hauppauge drivers responsible for the flagging of the fps of the mpeg stream?

[sub]

Are the hauppauge drivers responsible for the flagging of the fps of the mpeg stream?

Yes.