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View Full Version : Remove (electrical?) interference from S-Video capture


PlazzTT
28th December 2005, 05:35
I'm doing capture from a digital satellite box via S-Video cable.

When I look at the captured video (I used HuffYUV) on my PC's LCD monitor, I notice interference. (I had to raise my head to see it properly on my LCD screen, you might have to do the same).

You can see it in the black bars at the top and bottom of the screen.

http://x12.putfile.com/12/36022232866-thumb.png (http://putfile.com/pic.php?pic=12/36022232866.png&s=x12)

This interference looks like electrical interference caused by poor shielding in the S-Video cable? That's all I can think of, because the S-Video out of my digital box definately isn't outputting this noise.

Or maybe one of the appliances is not properly grounded (earthed) (my digital decoder, PC and TV are all connected to each other)

I've noticed that when recording audio, there is a slight buzz on the recordings, and this interference is probably the same thing.

Is there some filter that can capture a noise profile from the black bars, and use this to denoise the rest of the frame?

I've tried Deen, Convolution3D, and MipSmooth, but they all have very little effect on this kind of noise. I'm looking for a filter that can make those black bars almost perfectly black. I don't think a smoothing filter will be able to do this.

Any suggestions?

Revgen
28th December 2005, 07:20
Have you tried FFT3DFilter?

Fizick
28th December 2005, 08:57
Search Defreq, Fanfilter.

PlazzTT
28th December 2005, 16:19
Thanks.

DeFreq and Fanfilter seem to be for removing diagonal lines caused by interference. They don't have much effect on my video.

FFT3DFilter(sigma=6) works the best so far.

Here's a better screenshot of the noise. There seems to be a vertical band of noise in all my captures, always in the same place in the frame. I'm not sure if you can see it on all monitors, I've drawn a box around the width of it here, but it runs from top to bottom.

http://x12.putfile.com/12/36109241035-thumb.png (http://putfile.com/pic.php?pic=12/36109241035.png&s=x12)

FFT3DFilter does a good job, but that band is still there. This frame was using FFT3DFilter(sigma=6)

http://x12.putfile.com/12/36109310752-thumb.png (http://putfile.com/pic.php?pic=12/36109310752.png&s=x12)