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Old 9th December 2005, 17:51   #9  |  Link
Wilbert
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Join Date: Nov 2001
Location: Netherlands
Posts: 6,364
Quote:
(II)
When decoding from DV and output is YV12 you have to tell the encoder which type of YV12 output you want to get out of the decoder:
1.), 2.) and 3.) same as above but now specifies the output material.
4.) When decoding to YUY2 or RGB there is no uncertainty about the sample positions of luma/chroma, that is the "YV12 chroma sampling"-options are irrelevant.
Ok, now i'm completely confused.

Why is it that in (4) the chroma positions are not relevant? It seems to me you should know how to apply the weighting during upsampling. To apply the correct weighting you should know how the YV12 clip is sampled, thus you should know whether you are dealing with case 1, 2 or 3. Please clarify

edit: Ah, ok i got it now. "In order to get correct DV-compressed-video the position of the chroma samples are internally shifted/interpolated." So the YV12-input is resampled for the cases 2 and 3. I didn't know that, and thought that the YV12 would be left in tact.

Last edited by Wilbert; 9th December 2005 at 17:56.
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