bavc/avaa

Help Identifying this bizarre form of Interlacing + field shift? (I Think) - - - (Solved - Combing)

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Are there particular frames you'd like us to look at? There's so many here it's hard to figure out.

https://user-images.githubusercontent.com/54192936/114888073-478c1d00-9e4c-11eb-9912-2d594e030cb5.jpeg
Do you mean the hands here? That's just two moments in time captured across two fields that are merged into one frame. Using QCTools and the split fields view is fun here as you can see both undistorted images on their own from the different moments in time.

https://user-images.githubusercontent.com/54192936/114888073-478c1d00-9e4c-11eb-9912-2d594e030cb5.jpeg
Do you mean the hands here? That's just two moments in time captured across two fields that are merged into one frame. Using QCTools and the split fields view is fun here as you can see both undistorted images on their own from the different moments in time.

Yes , that's correct , QC Tools im not familiar with but looks really interesting. do you know if there is a specific name for this type of defect? And would you happen to know if there is a process in virtualdub2 to fix this issue.

Thanks for your help BTW. much appreciated

It's called combing I would say?
https://en.wikipedia.org/wiki/Interlaced_video#Interlacing_problems
There's example pics that match what you're saying.
There isn't currently an AVAA entry for this, but it's discussed here: #196 I'd suggest replying to that thread if you feel that it requires inclusion.

Technically it's not an issue, you wouldn't notice it if playing back the video on a monitor or tv that natitely supports interlaced content. These issues happen all the time when using our modern progressive playback displays.
Edit: As for virtualdub - I'm more familiar with ffmpeg, but using a good deinterlacer like yadif should improve the situation somewhat.

Also can you share the actual video please?

here's an example from a recent episode of below deck med:

image