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Old 28th September 2003
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trodas trodas is offline
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Quietseb - difference between mode1 and mode2 is the quality of colors & logically size of data, transferred trought bus (though it matter only on very slow systems)

The real technical difference is that mode 1 is YUV420 and mode 2 YUV422. No clue? Well, study YUV formats a bit

But i might give you a hint. YUV420 is 12bits per pixel, YUV422 is 16. 422 is used only for mpeg2 video and WM9 video, because of necessary color fidelity - 422 is same quality, as RGB32 ! :twisted:
(well, in fact, as RGB24, because the 8bits are just and unused overlay, but i don't want confise anyone too much)

420 is used mostly where size matters and color fidelity is not as big problem. Typically mpeg(1) and all mpeg4 formats (DivX, Xvid and such)...

Do you ever wonder, why some scenes rules on DVD and suxx on DivX? So, there is the answer - because all mpeg4 formats have crippled colors in order to reach their small size. Try watching The Abyss (opening sequence) or U-571 on DVDs and on Xvid. Especially underwatter scene of U-571 going inder Nazi chip are HORRIBLE into DivX or Xvid. See on DVD them and you don't believe own eyes.
Another case to watch are nice shades on empty sky around rising/dawning sun and scenes like this.
But that's the price (desplite the picture orginal size and lost sharpness) of puting DVD on CD and most users pay it gladly.

Well, one special thing - AFAIR IntelIndeo oldie AVI codecs using special, even crappier YUV mode, witch using only 9 bites per pixel. Old Cirrus/and other chips have a special mode for supporting this crap.

Conclusion - is not a big problem to play mode1 things into mode2 overlay. It could be a problem trying to play mode2 things (DVD/WM9) into mode1 overlay. Either the player did not allow it at all, or there are problem with colors :roll:
I don't know.
Never tried for myself.
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