Disappointing MPEG2 decoding

[Deusxmachina]

in any scene that has the camera panning - so for example - if the camera is panning from the top of a tall building to the bottom, or if it pans from left to right, or if an object on the scene moves consistantly from left to right; the screen shows little jitter and the motion is not smooth. I play the same videos in PowerDVD6, WMP11 or media player classic and the motion in the videos is smooth.

In case no one else wakes up soon, I'll take a shot. You didn't say exactly what you tried already, so this might be a repeat, but... yesterday I learned the hard way to turn off all the extra stuff in the video card settings. (In my case, ATI 2400.) Turn off or set to "set by other application" (or whatever similar setting) all the video card's deinterlacing, antialiasing, pulldown detection, etc. Once you get a stable picture, you can always experiment with adding them back in to improve the picture quality.

For me, turning off deinterlacing in PowerDVD helped the video skipping, even though I was using MPV for the video decoder. Hmm, I guess I was probably using Cyberlink for the muxer, though. I have deinterlacing turned on in Catalyst, so I wonder if they were fighting each other. Maybe yours is, too, or maybe yours is turned completely off. If a change doesn't do anything, just change it back. Turning off antialiasing in Catalyst completely fixed my video skipping problem.

It does sound like a deinterlacing problem as I've read elsewhere on here, but just turn all that junk off on the video card to remove it from the equation, and also check the deinterlacing setting in PowerDVD since you use Cyberlink codecs. And then if that and whatever else doesn't work, can always try some other codecs. Since you almost have a good picture, seems like it's just one bad setting somewhere, though.

[r3d]

Thanks for all the help so far. I will give your suggestions a go this afternoon when I'm back home in front of my tele. But in the meantime, keep the suggestions coming.

Since you almost have a good picture, seems like it's just one bad setting somewhere, though.

This is exactly my feeling. I'm so close to getting it to work perfectly

[cascaman]

sorry unless you tell me what resolution the digital media is that are playing back is i cannot help you

should be something like 720x576 interlaced pal B

One of the most important things for me is DVB-T viewing, so the mpeg stream of DVB-T use to be just what you say: 720x576 (PAL-B).

Looking up your tuner card, the description says it's an analog cable TV tuner as well as a DVB-T tuner, so I don't understand your DVB-T comments when your card apparently already is one. I don't understand if you think the card is at fault or if GBPVR is at fault.

Excuse me if you don't understand me. I'm sure it is my fault, as I'm from Spain and don't write correctly in English languagge. I'll try to explain again: my card has DVB-T turner. So I want to see DVB-T in my HTPC. But the image quality is very poor (is not clear, movements are horrible, etc.). And I wanted to compare the obtained quality of my system with a cheap DVB-T set (this is.. a box wich you connect to your TV using SCART and let you watch DVB-T in any TV and costs less than $50). The image of the $50 DVB-T box is far better than any HTPC with DVB-T tuner card and TV-Out I have ever seen. In fact, playing AVI's or DivX's happens the same: HTPC quality is very poor compared to cheap DVD players in the market. Do you understand me now?

I wouldn't worry much about getting a good picture on the TV before getting a good picture on the monitor.

Unfortunately I have not monitor connected to the HTPC. Only TV...

That way you at least know the picture is good and any bad quality is just a TV problem of some kind.

I'm not totally sure about that. In a PC monitor I should need deinterlacing and other image filters and adjustments for get a good quality. In a TV set, deinterlacing should be not necessary or at least, could need another kind of deinterlacing. And could need other kinds of filters or adjustments.

Do video files look good outside of GBPVR, such as with VLC player? That's a good benchmark since it's a self-contained player.

I'll try. Now I'm not in front of my HTPC now.
-----------------------------

Anyway, I think it is very difficult to get the perfect quality with this kind of systems. Two reasons: 1) because of the very poor quality of graphic card's TV-OUT (composite) and 2) the problems of interlacing / deinterlacing the signal. Always will be quality degradation in such this process.

[r3d]

Well! The good news is that I got it working.

As per the suggestions by all you kind folks I started with turning down all the settings in the ATI Catalyst. That did not make any difference for me.

Then I reset all my ATI Catalyst settings and started tweeking the GB-PVR config settings in the playback and DVD tabs. I started with changing the video decoders in both the tabs. No result. Then I started changing the renderer and I found that the jitter/tearing of the video disappears in all renderers except "VMR 9 Custom". i obviously did not like the picture quality of Overlay so have now defaulted it to VMR9 FSE. I'm not sure what's happening with VMR9 Custom but it produces the jitter/tearing of the image.

Hope this helps others out there.

Many thanks to all you wonderful people.

[Deusxmachina]

Anyway, I think it is very difficult to get the perfect quality with this kind of systems. Two reasons: 1) because of the very poor quality of graphic card's TV-OUT (composite) and 2) the problems of interlacing / deinterlacing the signal. Always will be quality degradation in such this process.

That's the main reason I thought you had a monitor and could remove the TV from the equation, since I wasn't sure what your picture quality standards are and to also bypass any possible tv-out video card problem.

But whatever video file you can play through VLC player or some other computer player, GBPVR can do similar/the same quality because it doesn't use its own player, it links to what is already on the computer. So, if you hook a standalone DVD player to your TV and get a good picture via composite, then VLC player on your computer hooked to the TV via composite should produce a similar picture using that same disc. If it can't, then there is something wrong with your computer settings or hardware, but GBPVR doesn't have anything to do with it (since VLC is a self-contained player and GBPVR can't use it).

Your computer specs look fine, so the important thing to remember is your computer is probably more powerful than any standalone DVD player or set-top TV box, and it just needs the proper settings. From what you're saying, even DVD looks bad from your computer, and it shouldn't, so I'd work on getting a DVD to play clearly before working on the TV card because that way you know what the source video is supposed to look like. With VLC player being self-contained, the only thing I can think of that can stop it from showing a good store-bought DVD picture is if there's a problem with the video card or the video card's tv-out and your TV.

[widman]

Here's a recap of what I gathered from reading the first part of this thread.

Go here to grab a copy of the earlier version of quartz.dll:

http://forums.snapstream.com/vb/showpost...stcount=26

I just did this fix by rebooting into safe mode and then I copied the existing quartz.dll from C\windows\system32 to a backup location and then copying the older version from above link into the c:\windows\system32 folder. I rebooted and then ran: All progams - accessories - system tools - system information
click on the tools tab and then directx diagnostics. Look for quartz.dll and verify that it has been replaced with the older version.

This seems to have made a difference on this pc.

I was having problems on my XP SP2 system and followed these instructions. So far, it seems to have removed the stuttering in the video playback.

pete

[carpeVideo]

I got a new HD motherboard which has improved my playback however with most decoders there is a creeping mismatch in my picture (looks like a line where the picture is shifted by a few pixels).

I have found the the ffdshow decoder doesn't do this using a graph or zplayer. However when I choose it as the default decoder gbpvr ignores it and used a different one. I have tried adding it in the config as ffdshow Video Decoder (what graphedt shows) and ffdshow MPEG-4 video decoder (what zplayer shows) but to no avail. Looking through the logs it shows that GBPVR is looking for the decoder but doesn't complain about not having found it.

Has anyone seen the above issue with the creeping mismatch line or the decoder issue and do you have any suggestions?

Thanks,

CV

[sub]

I have found the the ffdshow decoder doesn't do this using a graph or zplayer. However when I choose it as the default decoder gbpvr ignores it and used a different one. I have tried adding it in the config as ffdshow Video Decoder (what graphedt shows) and ffdshow MPEG-4 video decoder (what zplayer shows) but to no avail. Looking through the logs it shows that GBPVR is looking for the decoder but doesn't complain about not having found it.

It sounds to me like you either havnt enabled the exact type of media in the ffdshow settings, or you have ffdshow set to not autoload.

[carpeVideo]

I can't find a setting in FFdshow to do that - when I render an MPEG file in a graph and let directShow choose what it wants it picks ffdshow ffdshow video decoder as the default filter while zplayer chooses it as well but the returned name is ffdshow MPEG-4 video decoder. Do you think the different name may be having and effect?

[sub]

Set the video deoder to 'system default' in the config app, dont tick the 'use ffdshow post processing' option, then try playing one of these files in PVRX2, then zip and attach the PVRX2.exe.log and PVRX2.exe-native.log and I'll take a look.