Videos that were previously fine now appear with Green blocks and pixelation. Screen shot attached - note this happens across various sites, not simply universalsubtitles.org as shown. Also happens when playing files locally. Brand new install of Mac Pro, OSX 10.6.5, running trunk.

Is it every video, or only some? Please post a link to a video that's definitely broken for you. If you could test a nightly from before Nov 11th (candidate being bug 577843 and related changes), that would help narrow the regression range. Also, please paste the "Application Basics" and "Graphics" sections of about:support in this bug. I think OS X may be using OpenGL for Y'CbCr conversion now, in which case the bug I mentioned above is probably not the cause.

From Brett's screenshot: http://universalsubtitles.org/videos/lPjFVDYh3WoC/info/ http://videos.mozilla.org/serv/webmademovies/Patipat-02web.ogv The video is slightly scaled in the page (470x264 vs 480x270 native size). Does the direct video link work for you Brett, or does it suffer from the same problem?

Here's another video, guys - a direct link. http://videos.mozilla.org/serv/webmademovies/Bob-01web.ogv Screenshot attached to bug of what it looks like for me.

Note this seems to be intermittent. When I loaded the direct link from you in Comment 2, Matthew, it worked - after which the video I played in comment 3 worked. In cases where it happens, it also goes away after a few seconds.

Confirmed on 10.6 on my MacBook Pro. The first link above shows the green, the video itself is fine. I'll test a nightly from before Nov 11 next. Application Basics Name Firefox Version 4.0b8pre User Agent Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:2.0b8pre) Gecko/20101209 Firefox/4.0b8pre Profile Directory Show in Finder Enabled Plugins about:plugins Build Configuration about:buildconfig Graphics Adapter Description 0x22600,0x20400 Vendor ID 0000 Device ID 0000 Adapter RAM Adapter Drivers Driver Version Driver Date Direct2D Enabled false DirectWrite Enabled false GPU Accelerated Windows 1/1 OpenGL

Works on Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:2.0b8pre) Gecko/20101110 Firefox/4.0b8pre.

Possibly connected with bug 618458?

I mean but 620207.

Sounds like a regression from bug 577843.

I get this same issue with some Flash videos on Youtube as well.

Well, I assume it's the same. Similar green and black. eg: http://www.youtube.com/watch?v=pzcLTPy8yDQ

Comment 11 and 12 probably not related however as I can duplicate that outside of Firefox.

The graphics data from about:support in comment 6 shows that GPU accelerated windows are using OpenGL. Wouldn't this make bug 577843 unlikely? Is scaling on Mac OS X always through OpenGL?

That's a good point. This probably is an OpenGL bug. I hope you can still fix it :-)

I can reproduce this bug on my MacBookPro3,1 with a GeForce 8600M GT using the old nightly build David used (Gecko/20101209), but not with a current build. So this is probably already fixed.

Works for me, too.

Verified using Minefield nightly from 2011-01-22.