DVB & De-interlace

[BobBuilder]

I have a Novat-usb2 DVB and my understanding is that this will capture steams that are not interlaced so I should not need to worry about de-interlace settings or using a filter like dscalar etc.

My problem is that when viewing the output on my SD CRT via Radeon 9250 composite out I get a constant "jitter" especially evident when viewing side scrolling text. It looks like a field order / interlacing issue.

The streams play back perfectly via the MVP.
I have re-clock installed but get the same problem if its usd or not, Re-clock reports the stream as 25fps, and that the tvout is set to 50, the Ati drivers are also set to Pal.

Ive tried replacing the quartz.dll didnt help, I did see another thread that mentioned setting the tvout to be the primary monitor fixed a similar problem for someone else but I only have the tv attached so dont have this option.

Im not sure what to start looking at next, Im going to start trying different de-coders but I dont believe this will fix it.

I was considering attaching a dummy vga connecter so the card detects a monitor which will open up more options for display settings within the drivers but I would have thought since it appears to detect a PAL tv correctly that it should be fine with the default settings.

Any suggestions ?

[herbs]

You would be happen to be using the nvidia mpeg2 codec would you I find this gives me similar problems. Also are you using vmr or overlay as this seems to help me if its vmr.

[BobBuilder]

No Im using the Intervideo Haupage codec that comes with the Nova-t.
I have tried switching between both vmr and overlay and all modes have the same problem.

[sub]

It is most likely caused by the decoders being used, or another directshow filter installed. You'll see a list of what directshow filters and decoders are being used in your gbpvr.exe-native.log

[BobBuilder]

Ok thanks sub, ive downloaded the cyberlink decoders Ill give them a go tonight and check the logs for other filters.

Congrats on the new arrival by the way


bob

[BobBuilder]

Tried the cyberlink decoder on auto, force bob, and force weave and i still get the same problem.
The problem occurs in all playback, win media player, gbpvr, and wintv, which is not too surprising as they should all be using the same graph.

Ive attached the gbpvr-native log but I dont see any odd filters or anything i wasnt expecting.

I am at a loss as to what to try next, except maybe another decoder, Ive heard a lot of people use the mainconcept decoder but im not sure what app that comes with.

Im not conviced this is a decoder issue, I cant say why but I think its an issue with the gfx card tv-out (Radeon 9250). I run an older version of the catalyst drivers for stability reasons and Ive never fully understood the whole "theatre mode" stuff. Ill try upgrading the drivers and see if there are some more settings to play with.
Most of the settings ive read about are disabled in my setup as I only have a tv connected, the theatre mode / display clone stuff only seems relavent when u have both tv and monitor attached.
I was thinking of attaching a dummy vga connecter to trick the card into thinking a monitor was plugged in to open up the other driver settings, seems a bit odd though you would think the default tv-out settings would be fine.

My other option is to buy another MVP or even better, try and persuade the wife to let me buy a nice new plasma and then i can use DVI.

[sub]

Its unlikely to be the cause of your problem, but I should point out that the Cyberlink decoder is not compatible with VMR unless you add some registry settings. Google for 'Cyberlink EnableVMR9'.

[BobBuilder]

hmm ok Ill try messing with the Cyblerlink reg settings to enable vmr9 tonight.

ok so here are some random wonderings, can people please confirm Im not being totaly dumb here...

I beleive UK DVB SDTV broadcasts are all interlaced.

I am watching on a sd crt tv, and am assuming therefore that the tv output of the gfx card must be interlaced.

Since I have an interlaced mpeg stream and an interlaced tv out signal surely there should be no need to de-interlace the stream during playback ?

..unless perhaps the frame buffer that the video card outputs is assumed to be a 25htz progressive stream and that the video output circitry then re-interlaces ?


So the conclusion is that I need to de-interlace the signal, I did try the vareous de-interlace settings with the cyberlink driver, but this defaults to overlay (unless u tweak the registry).
Would rendering in overlay effect the way the de-interlace setting might work in my case ?
I intend to test the cyblerlink driver in VMR9 tonight.

Is there another option to not de-interlace the stream but persuade the card to not re-interlace the output ?
In the latest ATI catalyst driver there are settings for changing the de-interlace settings, how and when would these settings get applied ?

one last point...
I seem to remeber that with live preview using DVB the de-interlacing dialog in the gbpvr misc tab does nothing as this setting is for analog capture cards?

thanks for anyones input.

BOB

[sub]

You shouldnet really need to worry about deinterlacing with the standard setting of GB-PVR and/or your video decoder.

Zip and attach a screenshot of the problem sowe can see exactly what you're talking about. You'll need to get VMR9 working first though, so you can actually get a screenshot of the video.

one last point...
I seem to remeber that with live preview using DVB the de-interlacing dialog in the gbpvr misc tab does nothing as this setting is for analog capture cards?

Thats correct, it does nothing with DVB. It doesnt need to.

[BobBuilder]

Ok ill take a screen shot tonight.

thanks sub

bob