Need advice on color shifted in old anime vhs

[Tatjahna]

Hello all!

I need you to tell me if we can correct this problem even when it seems that this problem doesn't appear in the whole capture? .. Is there any filters and if so, what settings should I use to correct that assuming the image you see below :

http://www.b2solutions.ca/doom9/sample1.jpg
http://www.b2solutions.ca/doom9/sample2.jpg

The filter PeachSmoother was already applied on the 2 sample that you see..

Maybe just help me to correct at least a little this shifting to become less apparent?

Thanx in advance!

[Malcolm]

is this a constant shift? or does it move around? if it's constant, you can separate chroma & luma; move the chrome-plane an combine the 2 planes afterwards. This can be done with existing filters.
Here's a script that splits C&L, does something and combines C&L again.

AviSource("xyz.AVI")
orig = last

overlay = BicubicResize(8,6).BicubicResize(last.width, last.height).ConvertToRGB32()
overlay = resetmask(overlay)
base = ConvertToRGB32(last)

# chroma
mask_clip_chroma = levels(base,16,3,128,255,0)
overlay_clip = Mask(overlay, mask_clip_chroma)
final_chroma = layer(base,overlay_clip,"add",255,0,0,0)

# luma
mask_clip_luma = levels(base,16,3,128,255,0)
overlay_clip = Mask(overlay, mask_clip_luma)
final_luma = layer(base,overlay_clip,"add",255,0,0,0)


MergeChroma(ConvertToYUY2(final_luma), ConvertToYUY2(final_chroma))


Malcolm

[Si]

My Chromashift plugin should help you (with approriate Trim commands if the shift varies over the long term)

regards
Simon

[Tatjahna]

Oh Well!! Thanx guys!! It seems to work very well! :D

I have tried malcolm's method but I miss the dll reference to ResetMask() so I got an error. Just tell me malcom please where this function is? I am using Mpeg2Dec3.dll.

So I have jump to siwalters's solution, tried it and well it really works great! For sure, there's still shifting that I cannot correct since the colors seems to become larger than the edges of the "object", but anyway I don't mind for that!

I have used these settings :
ChromaShift(C=-4,L=-16)


Thanx for the help, now I will understand what is chroma shifting! :rolleyes: