Random colours on VHS transfer

[Chief Mouse]

Basically the image flickers with different colours constantly. I am aware this probably can't be fixed, but can it be reduced so it's not as annoying? Any Avisynth or VirtualDub filters that could possibly help?

And nope, I haven't got the VHS, I can't get a better transfer.

Example -

Frame 1


Frame 2


Frame 3



Video sample here for those interested - https://www.mediafire.com/?9utcekekcq14t50

[davexnet]

Apparently Mediafire blocked the file. Upload the file straight to videohelp.com
(upload files/manage attachments)



Thanks for pointing out the typo.

[El Heggunte]

Apparently Mediainfo blocked the file.

You meant MediaFire alright

File Blocked for Violation.

The file you requested has been blocked for a violation of our Terms of Service.

[Chief Mouse]

Bollocks. Ok, will do.

[ajk]

There's some pretty random stuff going on in the colour channels. Here are the Y, U and V channels after SeparateFields():



The luma channel (big image) is pretty consistent, though it seems to have some kind of combing left even though we are supposed to be looking at a single field only.

The chroma channels however are all over the place. The colour information is rolling around, maybe someone here can recognise what the cause is and properly reverse it. Here's a look with Histogram(mode="Color2"):



Here's a very quick brute force attempt at stabilising the colours so that the clip is at least watchable. With stage lighting like that, maybe it's not too important to get the colours exactly right anyway.

Source(...)

ChromaShift(-4)

SeparateFields()

MergeChroma(Blur(0,1), TemporalMedian(7))

Interleave(SelectEven(),SelectOdd())
Weave()

[Chief Mouse]

^ hey, thanks for this! Looks pretty impressive

But how do I get the script to work? It says "there is no function TemporalMedian". Is it a part of some sort of package which I don't have? Couldn't find it on the net.

[ajk]

It's available right here actually, see this thread

There are probably many things you can/should adjust, but hopefully you can get something presentable together.

[Chief Mouse]

Brilliant! Thanks for help

[lordsmurf]

It's probably chroma noise from the lack of a flying erase head in the VCR.
It's probably a re-used tape.

The Camcorder Color Denoise (CCD) filter for VirtualDub can help. (Better than Avisynth filters.)

[Chief Mouse]

It's probably chroma noise from the lack of a flying erase head in the VCR.
It's probably a re-used tape.

The Camcorder Color Denoise (CCD) filter for VirtualDub can help. (Better than Avisynth filters.)

I am aware of this filter. But my problem needs some sort of temporal plugin because the colour goes bananas from frame to frame. Ajk's suggestion works to some extent, although there are still some nightmarish bits like this that probably can't be fixed :P -

[ajk]

You could just kill the existing chroma completely and add a suitable tint to those sections, if nothing else works.

[mammo1789]

The Camcorder Color Denoise (CCD) filter for VirtualDub can help. (Better than Avisynth filters.)

I am aware of this filter. But my problem needs some sort of temporal plugin because the colour goes bananas from frame to frame. Ajk's suggestion works to some extent, although there are still some nightmarish bits like this that probably can't be fixed :P -

I think that CCD is temporal filter and it does great job

[poisondeathray]

I heard Freddy was a colorful guy


</bad joke>