The Best Way to recover old VHS tapes

[klode]

Hi,
I am dedicated to video editing for over 10 years. Now I am dedicated to the recovery of old VHS tapes.

Considering that my VCR is in great condition, I made an acquisition of an old VHS tape and I made a process with Avisynth. The result, in my opinion, is formidable.

This is the script used.

Import("C:\Program Files (x86)\AviSynth 2.5\plugins\TemporalDegrain.avs")
DirectShowSource("pionieri.avi").ConvertToYV12().Bob().ConvertToYV12().SeparateFields()
TemporalDegrain(GPU=true,degrain=3)
SelectEven()
MCTemporalDenoise(settings="low", edgeclean=true, ecrad=3, stabilize=true, maxr=2)
LanczosResize(720,576)

Indeed, even if not in proper form, I made a version at 50 fps.

However, there remains an effect (of which I do not know the name), a kind of vibration in the image, totally random. I leave you two short films (in MKV-AVC). One is an original feature, the other is the processed version.

Demo Processed

Demo Original

What do you recommend?

Thank you!

[Vidd]

DirectShowSource("pionieri.avi").ConvertToYV12().B ob().ConvertToYV12().SeparateFields()

Do not use SeparateFields() after Bob(). Bob makes the video progressive so there are no longer any fields to separate.

There is no need to call ConvertToYV12() twice.

If you use a Bob filter, use a smart Bob filter instead of the "dumb" Bob().

Temporal filters can be applied to interlace material without worry. You only need to separate fields when using spatial filtering. Use a filter that has an interlaced mode built in, or use a temporal only filter.

I use FluxSmooth with good results on VHS.
FluxSmoothT(int temporal_threshold)

Also consider a chroma filter if needed, like Cnr2()

[johns0]

Thread moved to restoration forum where you can get more help.

[danno78]

However, there remains an effect (of which I do not know the name), a kind of vibration in the image, totally random.

What do you recommend?

Thank you!

Vibration is time base errors. Can be fixed with by a feature called TBC (time base corrector) from high end S-VCR or external TBC, or some DVD Recorder in pass-through mode (Panasonic ES10 and ES15).

Time base errors have a negative impact on post-processing, especially on temporal denoiser.

[klode]

Thanks so much for your helps!

danno78 : Have you seen my movies? The problem of TB is the cause of that vibration you see in the video? Considering that the movie is in PAL, and I have a VCR output anlogica (but then no S-Video composite), what do you recommend to buy as an external?

Or should I use some special filter?

[themaster1]

Nobody in his right mind would use DirectShowSource to convert precious vhs tapes (interlacing, chroma artefacts, yv12> rgb mismatch...)
Instead they'd use AviSource and perhaps mention the fourrc and pixeltype in there to begin with.

Edit:
Oh yeah i forgot, when you use DirectShowSource the directshowsource filters (if you have some) are processed prior to avisynth filters, some food for thought i hope.

[jagabo]

The demo_original.mkv is already 50 fps progressive -- it has already been bob deinterlaced. And the source it was made from wasn't interlaced so there was no need to bob it in the first place.

If you are talking about the slight up and down bounce (one scanline) with every frame -- that's because the video was bob deinterlaced.

Time base errors cause individual scan lines to wiggle left and right with each frame. Get an S-VHS deck with built in line TGC to take care of that.

https://forum.videohelp.com/threads/306272-Computer-video-capture-vs-vcr-to-dvd-combo?p...=1#post1882662

Your black and white levels are a little off too. Blacks too dark, white's too bright.

[ronnylov]

QTGMC is a very good bob deinterlacer that avoids the up/down bounce vibration.
http://forum.doom9.org/showthread.php?t=156028

But (as jagabo told you) if your source is not interlaced then you do not need to deinterlace.

[klode]

to jagabo : the demo_original.mkv is deinterlaced because I've applied the same command of the precessed file, with the DirectShowSource() (SeparateFields() included).

to ronnylov : thanks for your notification of QTGMC, but my problem is not the interlacing, but the vibration due a TBC problem.

themaster1 : your help is so precious! thanks for your tip!

Now, this is the new script:

Import("C:\Program Files (x86)\AviSynth 2.5\plugins\TemporalDegrain.avs")
AVISource("video.avi", fourCC="MJPG", audio=false)
ConvertToYV12()
LeakKernelBob(order=0)
TemporalDegrain(GPU=true,degrain=3)
#SelectEven()
MCTemporalDenoise(settings="low", edgeclean=true, ecrad=3, stabilize=true, maxr=2)
LanczosResize(720,576)

The result is a little bit good rather than the other one (always on 50fps). The source is 25fps, but I'll try to make some on 50fps.

My qeustion is: there is a AviSynth script called TBC:

TBC

but I cannot understand how it works... Do you know any other software solution for TBC?

Thanks again for ALL of you! The results are bery interesting!!!!

[Gavino]

Do you know any other software solution for TBC?

See http://forum.doom9.org/showthread.php?t=152706.

But lordsmurf will tell you a complete software solution is virtually impossible, as he explains in that Doom9 thread.

[jagabo]

to jagabo : the demo_original.mkv is deinterlaced because I've applied the same command of the precessed file, with the DirectShowSource() (SeparateFields() included).

What's the point of providing an "original" that's not the original?

In any case, your original source still wasn't interlaced -- it was progressive PAL captured out of phase. Notice how every pair of frames is identical after the bob. All you need to do is restore the phase:

WhateverSource() # the interlaced original
TFM()

or

WhateverSource() # the interlaced original
SeparateFields()
Trim(1,0)
Weave()

[klode]

jagabo : I made the original file to show the effect of vibration on the frame, an effect not caused by interlacing, nor even by the noise, but the lack of the TBC.

About TBC, that plugin for avisynth, how does it work?

[jagabo]

About TBC, that plugin for avisynth, how does it work?

The one I've seen doesn't work, really. It looks for the first and last non-black pixels on each scan line then realigns and resizes the each line to the same length. It's easily confused by dark pixels in the picture, noise in the borders, etc. The video is usually worse off after the filter.

Some of the other software TBCs referenced in the doom9 thread appear to examine the image contents as well (and seemed to work better from the evidence presented). As far as I know, none of them is available as an AviSynth plugin.

[klode]

Hi,
I want to show the results obtained so far for the restoration of old VHS.
The only problem left is the presence of vibrations in the pictures. In its original form, are not very noticeable, but after an extremely clean images, are more evident in those areas where the view is fixed and there are vertical objects (such as doors or edges of the wall).

What do you think? Some video editing technicians have advised me to take a VCR with S-VHS. If I have some simple VHS, also work?

[lordsmurf]

What do you think? Some video editing technicians have advised me to take a VCR with S-VHS. If I have some simple VHS, also work?

Yes, quality VCR is a must.
S-VHS players play VHS tapes better than VHS players.

[jagabo]

The only problem left is the presence of vibrations in the pictures.

The videos you posted are no longer available and I don't remember what the vibrations were like. If they one line up and down bouncing from LeakKernelBob() then using a better bob deinterlacer will get rid of that bounce. Try QTGMC(). If they are film bounce from a poor transfer then you can try using Stab(). If they are from shaky camerawork you'll need DePanStabilize().