VMR9 Tearing

[Ryokurin]

No, I do not but I did.

Athlon 2100+ with 512m of DDR 2100 memory on a Radeon 9600. running winDVD 6 codecs.

What i've found is that if you go into the registry for WinDVD 6 there is an option for VMR support. if you have that enabled along with hardware encodeing then it goes away as well as a fair amount of CPU usage. (10% here)

[salsbst]

Originally posted by mlbdude
...
Has anyone else with this problem tried DX 9c? It was rumored to help this out.

I just upgraded to 9.0c last night and see the same amount of tearing as I did under 9.0b.

[stanger89]

FWIW, I've found a very insightful post about tearing, the thread is not specifically about VMR9 tearing, but an interesting post none the less:
http://www.avsforum.com/avs-vb/showt...04#post4146804

I can infer a few places where my system may fall short, possibly contributing to the tearing problem:
My Radeon 9500 non-pro has a 64-bit memory interface (low bandwidth)
It runs at AGP 4x in my mobo
I have single channel PC2700 DDR in my system

While it seems unlikely that any one of these alone is substandard, I can quite easily see, as explained in that post, that when you pile them all on top of each other it becoming a problem.

[kny3twalker]

I agree with everything he said but not the 8xAGP
I think you would see no difference between 8x AGP and 4xAGP
go lower and I know it would become a factor 1xAGP, 2XAGP, or PCI

[stanger89]

Like I said, I don't think any one of those things should be an issue, but I can see that between 64-bit memory and my rather slow system RAM, 4x AGP being the final straw. I know AGP speeds are a big issue when playing the WMV-HD stuff.

[kny3twalker]

Yeah but the last thing I hear is there is no difference in performance currently between pci express, 8x AGP, and 4x AGP
in gaming
not sure if HD could be more intensive
but I know VMR9 video rendering is not

[salsbst]

If I'm not mistaken, many of us are trying to render SageTV at HD resolutions using VMR9....and that is where we run into trouble. Most complaining about tearing here would probably have no tearing trouble at 480i.

[sleight42]

My Athlon client, after installing Sonic's cofec, can now run VMR9. I only get a stutter when I'm changing the volume. Otherwise, the picture is gorgeous! Before, I'd tried Moonlight, Cyberlink, and the default. Sonic made the difference.

[kny3twalker]

Yeah personally I prefer NVDVD 4
the playback is the smoothest I have seen wth any decoder while DXVA was enabled(good deinterlacing)
Cyberlink powerDVD does not supprt VMR9
only the ATI version does
and there is no such thing as default decoder
it was probably either cyberlink or moonlight

and salsbst
there is alot more information(data) for HD content(around 20GB/hour) than NTSC content and thats why I said that about AGP

I understand about VMR9 and HDTVs
and that it works fine on SDTVs

[LowTech]

So on the surface it looks like there are less issues with nVidia cards than with the ATIs.

Any other conclusions?

I'm using a Radeon 9600XT, NVDVD 2.55, overlay.

I got some tearing.

[stanger89]

While I won't say tearing is impossible with overlay, you should not see tearing ever with overlay on any card. So a 9600 not tearing with overlay doesn't really count.

[remmy925]

Sounds like to me, the real question is if the tearing on the systems is really tearing or something like caching. I think some people are getting confused with the results of low resources and the results of the video card not being able to keep up. Stuttering could be due to the PC accessing the HD and bad caching. It could be also due to low CPU or memory resources. I would suspect all the most recent DX9 video cards cards should be able to display the video without tearing. From what i can tell, my crappy FX5200 can do it without tearing. The problem I have with video is system caching. Video stops for a second or two and then recovers. I doubt that is a video card problem. More likely a resource problem.

[stanger89]

Well I know for sure that my Radeon 9500np can't do VMR9 at all, without tearing. It's unmistakable, the top and bottom of the picture don't match up. It's really bad.

[remmy925]

As I recall, there is an option for direct x called vsync. It makes the card wait till it has drawn the whole screen before it starts to redraw. Alot of gamers turn it off to increase frame rate at the risk of tearing. Forgive me, I could be wrong in this. This is just memory. I would suggest however looking into seeing if vsync is off or on. If it is off, try turning it on. May not be better for gaming but might fix your issue.

[stanger89]

Makes no difference, been there, it's enabled.

[mlbdude]

Enabling vsync does not eliminate the problem, just changes it. You go from tearing to occasional or constant stuttering. The latter is probably better, but still not desirable.

It really just comes down to GPU horsepower. On the ATI side at 640x480 I have seen a 9600 pro do VMR9 perfectly. On the nVidia side my 5700 FX can do it smoothly up to 740x480. Though I still get a stutter here or there.

[LowTech]

Well now maybe I'm not clear on what tearing actually is.

I'm not having issues with the top and bottom of the pic not matching up but rather an effect similar to zooming in on a digi pic taken with a low res camera. You know what the image is, it's just not coming together smoothly. The whole thing looks like its not matching...hard to describe really.

[stanger89]

This is tearing (with some help from photoshop)



Oh, and Vsync does nothing on my R9500, it doesn't change anything it still tears.

[remmy925]

Originally Posted by stanger89

Makes no difference, been there, it's enabled.

You got my interests sparked stranger 89. From what I can gather, VMR9 uses pixel shaders to perform filtering via hardware. The 9500 pro has twice the pixel shader power as the 9500 if I am reading correctly. It also isnt a direct-x 9 card. Although a DX9 card isnt needed, I suspect there may be some hardware optimization in DX9 cards to assist in this. Maybe more efficent use of pixel shader language. My 5200 I belive has same number of pixel shaders but does support dx9 (just way underpowered to make good use of DX9 features in games). It would be great if someone who knew more about how VMR9 worked could answer exactly what is going on. I suspect a card with more pixel shaders could render better at VMR9 regardless of shear GPU power. Anyone wanna answer that????? LOL. I am thoroughly baffled.

[stanger89]

First the 9500 is indeed a DX9 card, it was one of the first. Essentially it's half a Radeon 9700.

Personally I think there's something horribly wrong with either the drivers or hardware for my Radeon 9500. My understanding is that between the Force Vsync enabled, and from what Jeff has said (he mentioned a reg tweak that would force vsync) my card should not tear. Now whether it has enough horsepower to do VMR9 without studder is another issue. However the other issue here is that in general Tearing/studdering should be resolution dependant, ie at lower resolutions slower cards can do VMR9 w/o tearing, however my card (no matter which drivers) tears at any resolution.

FWIW, here's a very informative thread on the inner workings of PC video playback:
http://www.avsforum.com/avs-vb/showt...t=vmr9+tearing