Removing really bad noise

[MrKGB]

I have a VHS tape which is extremely noisy, I would say about 30% of pixels are noise. The good news is that the noise is random and well dispersed.
I want to convert this VHS to VCD .
So far my method is like this:
1. Capture at 720x576 , looks like this is better than capture directly in VCD resolution.
2. use AviSynth filters:
TemporalSmoother(20,25,25)
Convolution3d(....)
BiLinearResize(352,288)

The results are ok, the noise is gone, but there is a lot of ghosting.

Any better ideas?

[txpharoah]

1. Open TMPGenc Plus. Load your file.
2. Noise reduction filter
3. Do not use "high quality" mode. Stay regular.
4. Set filter numbers to 80-1-80.
5. See guide in my sig if you need other TMPGenc setting ideas.

I promise that you'll see improvement. I just ran an old tape with similar issues days ago, and the output is beautiful. No ghosting. Nothing bad at all. I was surprised at the output.

[kees1952]

MrKGB,
Temporalsmoother(20,.... gives you the ghosting. Try something like temporalsmoother (4,... Also try spatialsmoother() for the noise reduction.
Capturing in 720x576 and then bilinear resizing to 352x288 will smooth the video but this is an advantage for the VCD/MPEG1 encoding.

Regards, Kees Janssen.

[Oracle]

Have to agree with TX, give Tmpgenc a go, the results from the noise filter are excellent.

[SatStorm]

TMPGenc's noise reduction filter is excellent, but really slow.
I have almost the same results by using Dynamic noise reduction ( 8 ) and static noise reduction ( 4 ). Sometimes, I have to use simply sharpness (about 16) because those settings tent to blur a bit the picture.
Other solutions?

[DJRumpy]

I agree with Kees. Your settings are way to high. I would suggest the TemporalSmoother that comes with MPEG2DEC. It's faster than the built in TemporalSoften in AVISynth. It also seems to produce better output (your mileage may vary).

LoadPlugin("mpeg2dec.dll")
AVISource("c:\blah\blah.avi")
Strength=5
Radius=5
TemporalSmoother(Strength,Radius)
# or just plug the values directly: TemporalSmoother(5,5)


Use smaller strength settings for your temporal smoother. That setting is usually the culprit for ghosting. Try a range between 3 and 15 for your strength.

This filter only supports a maximum radius of 7, so setting it beyond that will gain you nothing. A setting of 7 scans 7 adjacent frames. Unless your video has no motion, a higher setting is pretty much pointless. Try to stick below 5 if possible. Higher strength values will ghost. I always use 2,3 for a dirty video (no pun intended... )

If the lower settings don't do the job, consider combining this filter with the built in SpatialSoften in AVISynth. Both together do an excellent job.

[MrKGB]

Thanks a lot for suggestions!

DJRumpy,
My settings are so high because the noise is high
If I set strength less than 25, i am getting not just a noise, but some kind of snow, only at 25 all noise goes away.
The Convolution3d is a combined filter: it has both temporal and spatial parts.

I will try tmpgenc and TemporalSmoother that comes with MPEG2DEC.

[DJRumpy]

One other suggestion. You should try the noise filter after reducing the size. The reduction in the size of the noise will make the filtering more effective.