Identify lines on VHS tape?

[wild_bill_az]

Hello,

I have a VHS tape that has a pattern of lines appearing throughout the entire tape. (Please see attached video clip). I have tried the tape in numerous players and they all look identical. The sound track appears to be fine with no drops or distortion. The tape and cassette look in good physical shape.

My workflow is: VCR(s) W/TBC > Frame TBC> ATI Capture Card > WinXP > VirtualDub

This is the only tape I have ever seen with this issue.

Any advise is appreciated.

[timtape]

The VCR doesn't seem to be mistracking. Looks like it's in the recording.

[aramkolt]

Another user posted something kind of similar with his betamax here in the last day or two. What his ended up being was interference from a switching power supply. I'd suggest moving the VCR far away from any other devices and see if you still have the issue or not. The fact that multiple VCRs do it says it's either interference that they are all being subjected to (which could actually be on your mains power line even). Remember back in the day when people would run vacuum cleaners and it would affect video signals like that?

The way I'd say to tell for sure it is on the tape is if you capture it and the "comets" are on identical places in each captured frame. If it's electrical noise or a grounding issues, then they'll appear randomly and not in the same place each playback. You could even capture twice on the same VCR to check for that.

[wild_bill_az]

Quote:

Originally Posted by timtape

The VCR doesn't seem to be mistracking. Looks like it's in the recording.

Bummer if it's burned into the recording. It's just such a bizarre consistent pattern that I've never seen before.

[timtape]

Playing well but with those same artefacts on various machines suggests it's in the recording. If the artefacts didnt appear, even on only one out of 10 machines, that would suggest it's not burned into the recording.

But I guess it's possible something common to all those playbacks caused the noise. Look for something like a device causing interference in your house or close to the VCR's, or play the tape directly to a TV set if you havent already done so.

[wild_bill_az]

Quote:

Originally Posted by aramkolt

Another user posted something kind of similar with his betamax here in the last day or two. What his ended up being was interference from a switching power supply. I'd suggest moving the VCR far away from any other devices and see if you still have the issue or not. The fact that multiple VCRs do it says it's either interference that they are all being subjected to (which could actually be on your mains power line even). Remember back in the day when people would run vacuum cleaners and it would affect video signals like that?

The way I'd say to tell for sure it is on the tape is if you capture it and the "comets" are on identical places in each captured frame. If it's electrical noise or a grounding issues, then they'll appear randomly and not in the same place each playback. You could even capture twice on the same VCR to check for that.

Yes I do remember!
I have all of my equipment connected to a Furman Power Conditioner. I also played a test tape to verify my equipment was not at fault. It's just that one tape having this issue.

The clip that I attached is the captured tape thru VirtualDub and it is identical to the non-captured tape. So it may well appear that the tape with the issue is a second generation that may have been captured with a power issue.

Another though is that it was originally captured with a cheap setup and they tried to de-interlace at the same time and it failed and created those lines?

[Selur]

SpotLess&co can help with that in post. (especially if there are just static images, SpotLess&co should work nicely)

[wild_bill_az]

Quote:

Originally Posted by Selur

SpotLess&co can help with that in post. (especially if there are just static images, SpotLess&co should work nicely)

I am not familiar with "SpotLess&co". Can you please explain?

[Selur]

SpotLess, DeSpot, KillerSpots are Avisynth/Vapoursynth filters.

[wild_bill_az]

Quote:

Originally Posted by Selur

SpotLess, DeSpot, KillerSpots are Avisynth/Vapoursynth filters.

We are using Hybrid to deinterlace and process our VHS files (HuffYUV format) using Avisynth to deinterlace. We have options under Avisynth but not those specific ones that you mentioned. Do you know if there are corresponding filters to those in Hybrid or is there a specific program used?

[Selur]

If you use Hybrid and Avisynth, Filtering->Avisynth->Other offers: DeSpot, SpotRemover, SpotLess all of them should help.

[latreche34]

While playing the tape in the VCR, hit pause, if the streaks freeze then it's in the tape, if not it's in the VCR/capture workflow, pretty simple.

[wild_bill_az]

Quote:

Originally Posted by Selur

If you use Hybrid and Avisynth, Filtering->Avisynth->Other offers: DeSpot, SpotRemover, SpotLess all of them should help.

Thank you Selur for the "Spot On" advice!

We did a test on a short video clip and there is definitely a difference. We are currently tweaking the radius value to reduce the lines as much as possible. Are there any major downsides to using the filters? Things to watch for that could be a negative result?

[Selur]

Depending on the filter and the settings, you might lose small elements in the clip that are in motion.
i.e. if you have a small hand, move fast

[Selur]

Shouldn't be an issue if your source only consists of still images.

[wild_bill_az]

Quote:

Originally Posted by latreche34

While playing the tape in the VCR, hit pause, if the streaks freeze then it's in the tape, if not it's in the VCR/capture workflow, pretty simple.

Excellent point!

It's definitely in the tape.

[wild_bill_az]

Quote:

Originally Posted by Selur

Shouldn't be an issue if your source only consists of still images.

The beginning of the tape consists of still images and then it goes into full video. The lines continue throughout the entire tape and are consistent.

Thankfully, your suggestion worked perfectly! We found that using DeSpot and SpotRemover together worked the best. I am amazed at the results!

Attached is a sample of the filtered clip.

Thank you Selur!

[Selur]

Also try SpotLess with a radius of 3 and maybe additionally add SMDeGrain with a radius of 2 or 3