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Old 31st December 2004, 14:12   #20  |  Link
Wilbert
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Join Date: Nov 2001
Location: Netherlands
Posts: 6,364
Hi guys

Quote:
You realize this disrupts the flow of the conversation? Anyway, I guess I'll wait a while and see if Wilbert has any thoughts to contribute. It seems to me a bit of a hassle to have to import an external VirtualDub filter to perform what (I believe) should be an inherent task.
Some random comments.

1) Tweak requires YUV (I corrected the info at www.avisynth.org).

2) HSIAdjust also required YUV (I corrected the info at www.avisynth.org).

Quote:
Thanks also for checking the HSIAdjust function. So are we to conclude that control of RGB saturation has never been supported in any version of Avisynth? (I'm shocked.)
Yup. A while ago I started porting Graft's hue filter to AviSynth. I will finish it one day. But, I'm not sure it will be faster than

clip.ConvertToYUY2.Tweak(hue=...)

The main difference is that with Tweak you have to rotate the entire range of colors, while in VD_Hue you can rotate just a few colors. I think TweakColor (by Trevlac) can do the latter though.

The problem with Graft's hue filter is that I don't understand where the hue transformation is coming from. Perhaps someone can explain it to me? The relation between hue and (r,g,b) is nonlinear, but it is linearized in some way. I guess I have to ask Donald about this when he comes back.

Quote:
It's too bad that AviSynth supports only YUY2 and YV12, though, which downsample the chroma.
AviSynth v3 will support YUV 4:4:4 as you probably know

Last edited by Wilbert; 31st December 2004 at 14:16.
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