Removing vertical waves from TV documentary

Hi everyone

I have filmed my TV screen and see vertical waves at times ( there must be a technical term for that but I don’t know it ), what video filter would you suggest to get rid of them?

Many thanks


PS: the technical term might be… deinterlacing ??

Do you mean that you pointed a camera at a television and recorded it? Can you share a screenshot so we can see what the waves look like?

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Thank you so much for trying to help me, Brian.
Yes, as you correctly assumed I did make a film with my Lumix camera on a tripod from my TV screen.
Here is a photo of the ugly lines

You need to make a fft out of every frame and reduce the peak points or areas from the fft and transform this image back to the visual area.
I did not find any video filter on Shotcut which can do this!
OpenCV can do this!

That is not interlacing. I would call that Moiré pattern - Wikipedia

I do not know of a way to remove that. If you need to capture video, I would recommend to use a video capture device rather than a camera recording a TV screen.

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The frequency peaks also cature the detail though.

The issue is that the camera sampling is misaligned with the display sampling, TV cameras fix this by adding an optical lowpass filter prior to the sensors.

Trying to remove it once it’s in a captured video signal is very difficult as it is mathematically the same as some of the wanted signal.

It also depends on the display technology.
When i film my IPS-Panel laptop monitor the quality is ok but filming my great VA-Panel Monitor returns really bad quality.

Well, well, it all sounds like I will have to leave it at that, this was not a work of art I was making anyway, just a recording of a cookery program. If no shotcut filter can help I will just call it a day.
And thank everyone for their support !

For me the topic is closed.
Take care, all

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