Fix for Directx 9.0c ff/rw deinterlacing problem

[mlbdude]

Originally Posted by Wheemer

I was successfully in my setup of Beyond tv in using 1024 x 768 at 60htz, it's going out though svideo.

So that's what I was trying with sage for the last few days. I've now switched to 800x600 in hopes of reducing these issues...

Don't forget too that if you are using SVideo if you output more than 740x480 your video card is having to scale down the image and you are loosing quality.

[Wheemer]

yeah that's understandable... However if I runs that resolution the video is inset from the side edges... I don't want to have to fiddle with ascpect ratio settings.

I watched The Tonight Show last nght as a test for panning tearing during the opening. It wasn't very good, all kinds of small jerks in playback.

To elaborate on exclusive fs some more I'll give you some examples... The exclusive fullscreen function in Beyond TV works very well for totally eliminating any of these issues. However, the entire full screen user interface invokes it's hold on the fullscreen at initial launch. This causes it's own problems, as if you do somthing on another monitor, the interface jumps back to windowed mode. This was one drawback to it. However the benifits of perfect playback outweigh this draw back.

If you've ever tried Media Portal, they have it incorporated much better. In Media the Fullscreen lock is only executed upon playback of fullscreen video. So everytime you launch something to play fullscreen the monitor filck a little as it enters exclusive fullscreen. This is an amazing thing, I absolutely love it. They way Media Portal does it combines the benifits of excellent playback, while still being able to use another monitor at the same time.

I really really hope and wish that Sage at some point in the near future strolls down this path. This issue is basically the only thing about Sage that I find lacking. In every other respect it blows the doors off the competition.

[mlbdude]

Well as I mentioned above running in exclusive fs for me on my BTV installation does not help tearing or stuttering.

The only applications I have tried that never tear are MCE and Mediator. For those, the authors had to write their own presentation layers to interact with DX9. From what MS says this is the only way to avoid tearing on an underpowered system.

Wheemer, for your video position issues, Sage has video zoom settings that you can use to adjust that. However, if you run using the Source aspect ratio with a video resolution of 720x480 you would be in Essenes duplication what a standalone DVD player does and should not have to mess with any of that.... unless your video card is not outputting overscan properly .

[tealcomp]

Originally Posted by tealcomp

Hey guys:

I am going to drop my resolution to 800x600 and see if things improve; I will report back when I have some definitive news..

-Dan

Welp for me anyway, dropping to 800x600 at 72Hz didnt do much if anything

These problems are really starting to annoy me. Is it worth it to submit these issues to Frey?? I mean it is clear that others are having very similar problems; there is already another thread open about picture quality.


-Dan

[mlbdude]

Depends on the issue. I think several are being discussed here. If it is tearing then no that is a normal VMR9 behavior. If not then please do. The more feedback they get the better.

[tealcomp]

Originally Posted by mlbdude

Depends on the issue. I think several are being discussed here. If it is tearing then no that is a normal VMR9 behavior. If not then please do. The more feedback they get the better.

Unfortunately, I believe it is the former and not the latter I just get such a better more accurate picture with it, it's hard to part with. I guess that I am just picky LOL..

-Dan

[Wheemer]

MlbDude

Yeah, I think my video card messes up when in 720x480 mode... at 800x600 and 1024x768 everything displays properly size-wise. The overscan settings in sage would affect playback of xvid/divx too, and these already display properly in 720x480. I think it has something to do with mpeg playback.

And although exclusive fullscreen did not help in your situation, I assure you that is WILL help in some. It's very well known about the buffering of the video in Sage's current display method. I think I read about it as avsforum.

In Beyond TV's eclusive fullscreen mode I get nothing but a perfect non-tearing, non stuttering VMR9 experience. And that's with a cheap old 440mx.

Sage needs to incorporate the viewscape switching into exclusive fullscreen upon Mpeg2 playback. And leave everything else the same. I don't think anyone expects them to go the Microsoft route and rewrite the code... But using this available VMR9 feature now would help a lot of people out.

[stanger89]

Actually I think it's a lack of buffering that causes tearing, games for example (which run in exclusive mode) use double or triple buffering to avoid tearing. dmunsil (IIRC) wen't into rather great detail about VMR9 and tearing over on AVS a while back, and basically doing what you describe requires writing a custom allocator-presenter such as used in MCE and Mediator.

Also, Jeff is aware of the issues, and is working on them. In a recent email (bug report thing) Jeff had me try something (didn't work unfortunately), so I know he's working on it, but I have no idea when it might make it in.

[Opus4]

Double buffering in games allows you to create the new screen & then immedaitely switch to it during the vertical blank interval when the electron beam is off & moving back to the top of the screen. (Triple buffering allows the game to continue drawing a 3rd screen while waiting for VBI once a new screen is done in the 2nd buffer instead of sitting idle while waiting.) Switching the active buffer any time outside of VBI can cause tearing in the displayed image.

I'm curious... is VMR9 simply not doing any sort of such check & you end up with the screen image changing at any time? Since it was using D3D, I thought it would have provided a way to handle such buffering to prevent tearing. Or, am I misreading what was said & VMR9 tearing is caused by something else?

- Andy

[stanger89]

I'd say that's a pretty fair description of what's happening. Yes VMR9 uses D3D, but my understanding is that it doesn't (or at least the supplied VMR9 renderer doesn't) use it in the same way as games.

From the descriptions I've read, with the default VMR9 renderer, or maybe allocator-presenter is more correct, there isn't anything to stop the switch from happening outside of VBI if the system can't keep up. Actually I'm not sure if default VMR9 uses any buffering at all.

A custom allocator presenter like used in MCE forces (or can force) the swap during VBI. It's been stated (on AVS by MS people) the VMR9 on MCE "will not tear" ever. I don't think they've ever said anything so definitive with regard to studder since I think if you don't tear, you can easily studder instead. Of course there's one more interesting bit of info about MCE, and that's that it uses YUV mixing mode, which is less resource intensive than the default (I think) RGB mixing mode, MSDN says 50-62.5% less bandwidth than RGB mode.

http://msdn.microsoft.com/library/de...mixingmode.asp

[jan smit]

Could somebody please explain to me what exactly is meant by the english (american?)expression "tearing".

Thanks

[nielm]

As with describing video artifacts in text, many people mean many things

But, what I think is meant here is one of the more common VMR9 bugs/issues:
The screen is split diagonally across the middle (torn in two / gescheurd ?), and the top-left part shows a different video frame to the bottom right part... In high-movement scenes, this is unpleasantly obvious, and you can see the diaginal line where the 2 frames join

(Some other people mis(?)-use it to mean the combing effects of bad de-interlacing)

[jan smit]

thanks nielm

[mlbdude]

With MCE tearing never happens. It does get to a point though that if you have a slower system or older video card stuttering can occur. Nice thing about MCE is that it runs full screen or windowed. Never a tear.

[kny3twalker]

with vertical sync enable
nothing should ever tear

at least true of video gaming

[Opus4]

Originally Posted by kny3twalker

with vertical sync enable
nothing should ever tear

at least true of video gaming

That's only true when using multiple video display buffers, which most games will do, or if VMR9 checks for sync.

If they are saying that VMR9 doesn't automatically allow the use of multiple buffers, then it can be difficult to write the entire screen fast enough to prevent tearing, which occurs when the electron beam catches up to where you are changing data in the display buffer. You'll end up with the top of the screen containing the new image & then below a horizontal line will be what remains of the previous image. The reverse would happen if buffers are used & you switch buffers in the middle of a screen update -- old on top; new on bottom.

If what people are saying is that VMR9 isn't paying attention to VBI when it switches buffers or isn't using buffers... then what did MS do? Make a poor public version & then write their own better internal version for MCE?? (There go the conspiracies again... )

- Andy

[mlbdude]

Here is a good response on that one....

AVSForums Response

[stanger89]

Originally Posted by Opus4

If what people are saying is that VMR9 isn't paying attention to VBI when it switches buffers or isn't using buffers... then what did MS do? Make a poor public version & then write their own better internal version for MCE?? (There go the conspiracies again... )

I could be completely wrong on this but...

My guess is that the VMR9 (and VMR7) renderers are written in such a way that they play nice with other things, ie they run in windows, they let you switch in and out of fullscreen, to different apps, etc. They are written so that they can be used easily without causing problems. This results in the unfortunate side effect of not being able to use buffering or force Vsync.

Now the only way to fix this is to throw VMR9 into a more exclusive mode. Games run in a totally different mode. Anyone who has run games on windows knows what I'm talking about. Games don't like you alt-tab'ing them, changing resolutions, minimizing them, etc. If VMR (7 or 9) ran like that it would be very bad for the more casual uses (watching a vid in a window while you're surfing).

The solution is for "hardcore" apps (like MCE, Sage, ZP, etc) to write their own allocator presenters.

Just my guess on the subject.

[Opus4]

I'm not certain what it takes to write a custom allocator /presenter, so I'll leave that one alone.

Originally Posted by stanger89

Anyone who has run games on windows knows what I'm talking about. Games don't like you alt-tab'ing them, changing resolutions, minimizing them, etc.

I know this is OT, but since it was used as a comparison here... Just so you know, though: it _is_ possible to make a DirectX game work just fine for alt-tabbing and/or switching between windowed/full-screen mode. The core DirectX code I wrote for my own games quite a while back worked perfectly fine for all of that. The problem is that it takes quite a bit of work to handle reallocating all the buffers and reloading all the images, so not all game dev teams take the time to write that code & the reloading process can take quite a while for a large game anyway. Some commercial games support this; some do not.

- Andy

[Wheemer]

Though it is certain that a custom allocater may be the permanent fix for this problem, I start firm on my recommendation to include Exclusive Fullscreen capabilities. As I know it, this would not be terribly difficult to impliment, and can certainly be a configurable option. Although this may not be the "ideal" long term fix, it would help some of us out in the meantime.

On a side note, Is the reason I am experiencing this Juttery playback soley because of my underpowered video card? Would upgrading to a newer fully directx 9 compliant video card solve this? Or would I need to go a little further and get something that is not the minimun, like perhaps a 9550 or a 5500, both with 128bit ram interface??

I did try out a basic 5200 with Beyond TV and it was not as good as my 440mx. There was white blocking around tickers.

Thank you