Deoldify Vapoursynth filter

[Dan64]

I'm happy to know that this version works.
Frankly I made so many changes to the code, that is difficult to me find the one that fixed this problem.

Among the many changes I have made in the new version, there is the stabilization of DeOldify's models: Artistic, Stable, which now can be used with confidence in the colorization pipeline.

This new version, support the new combination:  ColorModel="Artistic+Artistic" which is missing in the current Hybrid implementation.

-> It would be nice if you can add it. 

The most colored (but even the more unstable) combination is provide with the following settings:

clip = havc.HAVC_main(clip, Preset="medium", ColorModel="Artistic+Artistic", CombMethod="Simple", VideoTune="balanced", ColorTemp="low", ColorFix="violet/red", FrameInterp=4, ColorMap="none", ColorTune="light", BlackWhiteTune="light", BlackWhiteMode=0, BlackWhiteBlend=True, EnableDeepEx=False, enable_fp16=True)

My preferred colorization settings is this one

clip = havc.HAVC_main(clip, Preset="slower", ColorModel="Artistic+Modelscope", CombMethod="Constrained-Chroma", VideoTune="vivid", ColorTemp="low", ColorFix="retinex/red", FrameInterp=4, ColorMap="red->brown", ColorTune="medium", BlackWhiteTune="light", BlackWhiteMode=0, BlackWhiteBlend=True, EnableDeepEx=False, enable_fp16=True)

It is slow (even with FrameInterp=4), but it produces stable colors. A big contribution to color stability is provided by  CombMethod="Constrained-Chroma" which is very effective in mitigate the color instability provided by DDColor, as you can see looking to the following comparison (pay attention to the pillar planted in the ground on the right): HAVC 5.6.5 RC1 


Dan