Playback on computer: Purple Haze

[tempac]

Hi,

I am using the DivX Create Bundle that was recenly given away free and have a problem with playback on my computer and media center after it's installed. The problem is that any files that invoke the divx codec playback with a purple 'haze' over them. As though someone has put a purple filter over the camera they used when recording the orginal source material.

Can anyone explain to me why this is, as it never happened to me when using Divx Profesionall 5.1... I'm beginning to wish I hadn't upgraded now and had backedup my old copy of 5.1 instead of relying upon the new Version 6.8.0.

Thank you for your time if replying.

Edit: Oh yes, It's probably worth mentioning that this is a fresh installation of windows xp pro, I have no 'codec packs' installed, other than those used by windows and whatever vlcplayer has installed. As well as the divx create bundle described above.

[poisondeathray]

Have you changed the settings for DivX playback?

right click the icon => DivX toolbar configuration => Playback (you can adjust brightness, contrast, saturation)

What software media player are you using? any filters?

[jagabo]

Play a video in two palyers at the same time. Does one look OK, the other not? If so, you just need to adjust you graphics card's video overlay proc amp settings.

[tempac]

Hi poisondeathray: Thank you for taking the time to reply. I don't seem to have an entry for the configuration utility at least not under Start\Programs\DivX. I can however click on 'Configure Divx' and then a config box appears.

They say a picture speaks a thousand words, so here's what I'm looking at:









I did try to capture an image of the 'purple haze' but unfortunately I can't seem to manage it, all the 'caps' that vlcplayer captures look perfect. As you've probably guessed, I am using http://www.videolan.org/vlc/ to the best of my knowledge, it just uses a standard mpeg decoder when double clicking on an individual .vob file or .avi.

I also have: Xvid-1.1.3-28062007 _Final Release_ installed which seems to work perfectly, at least decoding xvid content, it's just anything that invokes divx where the problem lies.
Thank you for taking the time to reply.

[jagabo]

I did try to capture an image of the 'purple haze' but unfortunately I can't seem to manage it, all the 'caps' that vlcplayer captures look perfect.

You definitely have a video overlay issue. This is quite common with fresh installs and graphics driver updates. Go to the graphic's card's setup applet and ajust the video overlay settings.

Oh, one other possibility -- there is some kind of problem with video overlay and certain frame sizes. I think Divx and overlay with frame sizes that are less than a multiple of 4 (642x480 vs 640x480 for example). Some players seem to handle this better than others. And with some players you can choose another video overlay method.

[tempac]

Play a video in two palyers at the same time. Does one look OK, the other not? If so, you just need to adjust you graphics card's video overlay proc amp settings.

No it seems that one is 'bright pink' the other 'hazy purple'.

Thank you for contributing.

[tempac]

.... Well I'll be ... I entered Control Panel, then nView Desktop Manager then hit the 'Turn On nView Desktop Manager' (I've no clue what that did or the repercusions) but then played various files and true enough the purple haze has gone and the image looks just as natural as it was supposed to do.

Many thanks to the both of you.

I don't suppose anyone can give me a brief insight as to what this 'video overlay' thing is all about can you? As I've not discovered it before.

Thank you once again.

[jagabo]

I don't suppose anyone can give me a brief insight as to what this 'video overlay' thing is all about can you? As I've not discovered it before.

In the old days, graphics cards weren't powerful enough to display full screen video. The solution was to use a separate video card, daisychain the VGA output from the computer to the video card, then the video card would overlay the video onto the signal and send the final output to the monitor. The graphics card told the video card where to put the video by making a hole in the desktop (a rectangular block of a specific color that was unlikely to be used for other things on the desktop). The video card would scale and move the video to the hole.

Modern graphics cards have enough power to play video but the same basic technique is still used within the card. A hole is marked on the desktop, and the video is displayed in that hole with the graphics card's hardware overlay ability. This has several advantages. The video can be left in its native colorspace (YUY2, YV12, etc) so the processor doesn't have convert the video to RGB, the graphics card can use a hardware scaler so scale the video to the window or full screen, the video overlay can have its own brightness and color controls, many graphics cards have the ability to display the video full screen on a second monitor or TV even though the video is playing in a window on the main monitor, etc.