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Old 22nd October 2006, 03:03   #257  |  Link
tritical
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Join Date: Dec 2003
Location: MO, US
Posts: 999
Quote:
^If that's the case, to use the interlaced parameter for telecined material. Wouldn't the progressive frames be handled incorrectly?
They wont be handled as well as they could so to speak, but it wont really change much overall. It's a lot like using converttoyuy2(interlaced=true) on progressive YV12 material. The difference between that and using converttoyuy2(interlaced=false) on the same material isn't that great. However, using converttoyuy2(interlaced=false) on interlaced YV12 material will give quite a big difference vs using converttoyuy2(interlaced=true)... at least in areas of motion.

The reason is that when you use interlaced=true you're making luma lines 0/2 use chroma line 0, luma lines 1/3 use chroma line 1, etc... instead of making luma lines 0/1 use chroma line 0, luma lines 2/3 use chroma line 1, etc... as would happen with interlaced=false.

The difference between those two isn't going to matter much when used on progressive material since everything comes from the same point in time. However, with interlaced material where every other line could be from a different point in time the mixing of chroma from one field with luma from another (which happens with interlaced=false) can cause very visible artifacts.

Unless you have clips with changing colorimetry that you need to handle, I would recommend using:

mpeg2source("d2v.d2v")
ivtc()
colormatrix(d2v="d2v.d2v")

I've only seen a handful of clips with changing colorimetry, and most of those just had small sections at the beginning of pure black frames which had a different colorimetry than the rest of the clip. In those cases, where the difference doesn't really matter, I just change the first line or two of the d2v so that the colorimetry matches the rest of the clip.

Last edited by tritical; 22nd October 2006 at 03:15.
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