What codec 'error' creates this effect

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http://www.youtube.com/watch?v=p-Q_sGBlDEc
^ youll like this one

http://www.youtube.com/watch?v=mZrqZVi8LjM
^ also

http://www.youtube.com/watch?v=TxFeesWL5OI
^ warning annoying pop music

I remember it used to happen to me alot when I watched videos ~5 years ago, with avi’s in particular

what about avi’s allows this to happen?

is there anywhere i can even read more about avi’s and this sort of thing in general? thanks.

Honesto John

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Try:
WMP - tools - options - performance; and uncheck video acceleration. try in this tab.

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i tried that in windows media player with a couple avi files, it was just alot rougher images.

i think its got something to do with some type of 'reference keyframe' that comes before a section which designates colors for a length of time. idk what the proper terminology for that is though,

so theres no what to edit/alter what i just described above, or use the 'wrong' codecs so that will happen?

thanks.

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I get these mostly when they’re some flavor of MPEG-4 (usually DivX), and corrupted (some of the data in the middle is corrupt).
Also I’ve noticed some DivX movies can’t be seeked. If you do that, you’ll get the mentioned effect, even if you try it in VirtualDub. (In VirtualDub you can only move the time cursor to a keyframe, otherwise you get that effect - it plays just fine though). In many cases, such movies have been further shrunk with compressavi, a utility that reduces DivX files further.

As for the technical details as to why or what those artifacts are, I think you should ask the people on multimedia.cx or doom9.org. I’ve always thought you needed a good grasp of MPEG or H.263 quantization and DCT (Discrete Cosine Transform) to understand it, that’s why I never really bothered to look it up.
If you do find the answer, by all means, post back!