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[raym]

I've been chasing this problem down for days.

My video setup: amd 5450, direct to a plasma tv. Latest drivers. Windows 7 x64.

The problem: At seemingly random times while watching video (specifically, DVR-MS and DVD) I see extreme pixilation - large patches of colour flashing across the screen. Similar to a case of bad OTA signal breakup. There's no pattern to it. As far as I can tell, it started from around build 50. I've not seen the issue during bluray, avi or mkv playback. Just my dvr-ms and DVD collection.

Things I've tried:
- updated drivers
- ROST and HQ
- video accel on and off
- video clock on and off
- aero on and off (causes other pq issues when off!!)

After doing all of this I finally resorted to using ROST with ffdshow for all
Mpeg2 and DVD decoding (instead of the default LAV decoder). Problem solved!!!!

Any idea what's going on here? Anyone else seeing this?

I'd rather not have to resort to a non-std video config if possible.

Thanks.

[JimH]

I've seen the same recently.

[Hendrik]

A sample of such a file would be useful.

Also, i just today fixed a small mpeg2 parsing bug, which may (or may not) be responsible.

[raym]

A sample of such a file would be useful.

Also, i just today fixed a small mpeg2 parsing bug, which may (or may not) be responsible.

Sounds promising. Is there a way I can test this for you?

Alternatively, happy to attempt sending you a sample file but on a short sample, you may not see the problem. It's such a tricky issue as there's no way to reliably reproduce it.

As I originally experienced the issue with a DVD disk, this might be the way to go. I'm in Australia though so PAL here (in case that's relevant).

Thanks.

[JimH]

A sample of such a file would be useful.

I don't think it depends on the file.  It may be with DVD's.  Sorry I can't remember the details.

[raym]

I don't think it depends on the file.  It may be with DVD's.  Sorry I can't remember the details.

It does for me in as much as it must be mpeg2. So as you said, DVD is a good example.

I dont recall seeing the problem with non-mpeg2 content.

[Matt]

DVD probably uses the Microsoft decoder.  You could right-click while playing to check.

[Hendrik]

Now that Matt says it, its quite obvious. DVD is not LAV (yet), and DVR-MS might not as well, not sure about that.

[raym]

Ok you're both absolutely right. Forget LAV - it's the MS video decoder being used by default for both dvrms and DVD playback.

Sorry for the confusion.

So, what's going on?

If I substitute the MS video decoder with ffdshow for both file types, the problem goes away. Since I've been using the MS decoders forever without a problem, I suspect the problem still relates to something in MC. I went back to build 39 (the oldest I had) and all video playback is fine.

Could the recent custom video codec features have introduced this?

[lowjoel]

I was doing some research (before) to see if I could get my h264s playing back in MC with DXVA (old laptop here), and found that the MS Video decoder likes using DXVA for video acceleration. Not that DXVA is bad in itself, but ATI's video cards, while officially supporting the h264 main profile, does not support anything more than that. As a result, even slightly over-specced input can cause the display card to choke (which is what I observed) and giving the blocking/gibberish for those few frames. After the data stream goes back to standard, and the card's memory is replaced completely with fresh information, the situation abates.

I'm not sure if this is completely to blame in this case, but I thought I'd share what I know. I'm using software decoding almost exclusively now.

[raym]

This is driving me nuts. I've tried disabling hw accel in MC's video options but it doesn't make any difference. Played with every conceivable ATI driver setting.

If it is dxva related, it's a new problem. Build 39 works flawlessly. I guess I could try to work out exactly which build introduced the issue but I could be a while as it can sometimes take ages for it to show itself.

Jim, have you happened to see the problem again over the weekend?

[raym]

Bump