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  1. Member
    Join Date
    Aug 2003
    Location
    Colorado Springs CO
    Search Comp PM
    I ran into this one today and was baffled. I usually capture from my trusty old AIW using VFW driver and VirtualDub, capturing to avi with a variety of codecs. I've never had any sort of color problem.

    Recently I've been playing with Ulead's VFW MPEG driver and trying some captures there (straight to MPEG-2). It was happy while I captured to 640x480. But, today I discovered that at capture resolutions of 352x240 and smaller, the hue gets messed up in the capture. The overlay preview looks perfectly normal, but when played back, the capture displays flesh tones looking blue (yep, like the Intel blue-guys). I rebooted and confirmed the corruption was real. And I repeated the test multiple times and at different resolutions. Weirder yet, opening the capture into VirtualDub so I could adjust the hue and recover the correct colors, I discovered that there was no hue setting that would correct for the strange colors in the capture.

    As a final test, I switched to Ulead's DSW MPEG capture driver. Using this driver, all captures were back to normal, with no color problems.

    I know this is outdated Ulead software and I have alternate capture methods that work well, but it bugs me that I can't capture 352x240 directly to MPEG-2 without getting this color corruption. Has anyone out there ever heard of this and found a solution?
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  2. Member
    Join Date
    Aug 2003
    Location
    Colorado Springs CO
    Search Comp PM
    I found the answer to this puzzle and want to report so the next guy looking for a solution finds some help here.

    The problem causing the blue flesh tones and strange hue is that a bug somewhere in the capture driver is causing the U and V chromanance channels to be swapped. A solution can be found in AviSynth 2.5. Use the SwapUV() function to swap things back around, then the colors are just as they should be once again.

    Unfortunately, using AviSynth means my MPEG-2 captures need to be decoded, processed, then reencoded to be made usable. One might go this route if very short on disc space, frameserving to avoid the need for an intermediate file. Otherwise, for me, its not worth it. I'll just go back to capturing to AVI formats that work without the extra hassle.
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