VirtualDUB does have excellent filters, but not as good as a dedicated filter. Its all in the detection rates for deinterlacing and AVISynth is way superior in that if you use Neurons Decomb filter. This is what professional people use.
Also, yes, DVD is YV12. It goes through a conversion to YUY2 before it hits your computer screen or even your TV. I'll take a screenshot of what it looks like native - its all purple shades and ugly. VirtualDUB cannot decode it without loading a YV12 filter either.
Here is the breakdown:
DVDs - These use MPEG2 with 4:2:0 YUV (YV12) color. There is one chroma sample for each square of 2x2 pixels (unlike the YUY2 picture above which has one chroma for each group of 2x1 pixels).
DV - This uses 4:1:1 YUV which has the same number of chroma samples as MPEG2 but in a different order.
Mjpeg - This can use all kinds of YUV sampling but 4:2:0 (YV12) is very common.
MPEG1, 2 and 4 (divx etc) all use YV12 color (although they can technically support other YUV modes in theory, just not in practice). There are MPEG2 profiles (such as the Studio Profile) which can deal with 4:2:2 chorma but mostly you will see 4;2:0 chroma being used.
HuffYUV - currently YUY2 and RGB storage is possible. YV12 is developmental.
HuffYUV is my favorite lossless compressor. You can squeeze about 140 GB into about 40-80 GB.
-S
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