Picture goes green and wobbly VHS tape?

[koberulz]

Is there anything I can do about this? I'd like to get rid of the green effect at least. At a guess one or both of the chroma channels is reading wrong? Not sure whether to try and adjust that channel somehow, or switch the channels or something, or whether copying the chroma from the good frames would work somehow?

The wobbly lines and massive white blocks (WTF are those?) are unlikely to be improved, I'm guessing, short of full-frame replacements.

The other possibility is it being a capture issue, but it happens on both my Philips and Panasonic decks.

[koberulz]

I've also got a sudden burst of brightness here.

[lordsmurf]

Timing issue.
AVT-8710 in workflow, correct? Then not anti-copy based timing issue.
Possible VCR issue.
Possible signal issues, embedded in source recording.

Timing issue presenting as chroma flaw. Luma is showing, chroma disappears when green.
The visual distortion is timing.
Chroma disappearing is side effect.

Brightness burst (blooming = jargon, I think) attached to visual distortion as well. Probably the tape at fault.

[koberulz]

TBC-1000, not AVT, but I'm guessing there's no difference in terms of the point you were making. Not a commercial tape, anyway.

It's not constant, the attachment is literally every problem frame in a capture over 2 hours 12 minutes (well, except for the last 10 minutes or so, which I'm still checking). The rest of it is fine.

Doubt it's a VCR issue as two different machines rendered two identical captures, at least as far as this particular error goes.

Quote:

Timing issue presenting as chroma flaw. Luma is showing, chroma disappears when green.

Not sure I understand this.

Is there anything that can be done to make it look nicer?

[koberulz]

Found another one. Wonder if the grey graphic is a coincidence.

I'm obviously not expecting perfection but is there any way to neaten it up a bit?

[lordsmurf]

A. Ignore it.
B. Replace frames manually.

I've never done the replace via Avisynth, only in Premiere (rarely!), but will soon be learning it myself. I have a few important family video that needs detailed processing on a short 12-minute clip. In general, even film producers using analog sources are not so anal as to toss fits over 1 frame. It really depends on the use importance. The ROI to fix it does not exist, even ROI (ie unpaid) for personal project.

[koberulz]

Replace them with what, though? I figured that's how the fix would have to be implemented, but I'm not sure what the fix is.

[lordsmurf]

Replace with previous, next, or frame generated using mix of the two.

[koberulz]

So just duplicating frames or ReplaceFramesMC()? Nothing I can actually do to fix the green?

[lordsmurf]

You problem is 4-5 frames long, accompanied by timing problems. It's not just green.

There are some median and temporal NR filters that will take data from multiple frames, and average the info to remove small artifacts (especially single-frame length), but know that your issue is more than green frames. The frame both moves and breaks.

It's also behind the upper left logo. So it was in the source signal, not your tape.

[koberulz]

Yeah, I noticed that.

The green bothers me more than the other issue. I've gone through one and used MergeChroma along with RemapFrames to swap in the chroma from the nearest good frame while retaining the luma. Seems alright thus far.

It's also in a perfectly repeating pattern of five good pixels followed by three bad pixels. Took me about two seconds to whip up a mask, not sure if it's worth going through and manually shifting, though. Probably not.

There's one during the first half of the game, but I have the first half taken directly from one of the cameras so I simply cut away to that angle for a bit. Works perfectly.