Vertical Color Banding in DivX 3 movies

[dimitrik]

Hi

I have some cartoons encoded with DivX 3 Low-motion. They're pretty old. I don't know what the original encoding settings were.

The problem. When I play them in Win Media player (also things like PowerDVD etc) they display these ugly Green Color blocks, like a big vertical band in the middle of the picure. I actually think these are displaced colors because the rest of the picture has no green at all.

However if opened in DivX player or Virtual Dub the look fine.

Is there anything I can do to fix them? I thought of re-encoding in the latest DivX to try and get a more 'compatible result'but I don't know what settings to use...

Any ideas - has anyone else come accross this?

[Enchanter]

Try FFDShow for decoding the DivX 3.11 contents...

[dimitrik]

I'll try that, thanks.

Is there a way to permanently fix it?
Or does it not need it fixing, i.e. it's just a wekaness of the other decoders?

[Enchanter]

"Is there a way to permanently fix it?
Or does it not need it fixing, i.e. it's just a wekaness of the other decoders?"

"When I play them in Win Media player (also things like PowerDVD etc) they display these ugly Green Color blocks, like a big vertical band in the middle of the picure. I actually think these are displaced colors because the rest of the picture has no green at all.

However if opened in DivX player or Virtual Dub the look fine. "


Looks like a decoder problem to me. Let's see if FFDShow does its magic here.

[dimitrik]

OK, I tried FFDShow, but it didn't work - the problem is still there

I've actually realised what the problem is however - the Green collor is displaced and is displayed on the oposite side of the screen - its pretty bizarre but I have several cartoons (downloaded - not my onw encodes) that have the same issue.

All I can think of is to try and re-compress them.

I hope that if I set the encoder to the same bitrate as the original file, there will be no degradation. Are there any settings I should use to ensure the output is as close as possible to the original?

Thanks for any advice...

[Enchanter]

"Are there any settings I should use to ensure the output is as close as possible to the original?"

The best solution would be to avoid re-compressing them altogether.

Try updating your video card driver (and, if necessary, DirectX) first before doing anything else. Make sure that your desktop colour depth is set to 32-bit as well.

[dimitrik]

Yep, that's all done - latest Drivers (my card is a Matrox anyway, it never has display problems with 2D graphics), latest DirectX, 32 bit color, all checks.

I did a test and re-encoded a portion of the file with the latest DivX, using a marginally higher max bitrate than the original (with the quality settings & psychovisual on slow).
I got a perfect file, slightly bigger than the original but it plays right on all players, and looks identical in all other ways, so no visible loss of quality.

I'm not sure if the identical quality is because the source was a cartoon that was not very well encoded in the 1st place (only 500kbps), so it had already lost a lot at theat stage.

I really should try it on a purer source to see what will happen, but my PC's kinda slow, so I might not bother...