Lines in captured VHS footage?

[skycaptain09]

Hello all,

I've been a lurker here for a year or so now as I go on and off of working on capturing all of my family's old VHS home movies and recordings. It's amazing how much great information is available on here. Anyway, I'm finally comfortable with my capture setup so I've been working on it quite a bit recently and I've made it through about 30 tapes. While many of the tapes have played back very well, there are 2 different issues that I've seen come up on a few different tapes, and I'm hoping you can point me in the right direction on whether you think it's a tape or VCR issue.

My capture setup:
JVC 9800U -> AVT-8710 (green) -> ATI USB 600 -> VirtualDub on Windows 7

The first issue (Line in picture.avi) is where a line shows up in the bottom 1/4 of the picture. It will come and go throughout playback. The example clip here is from a TV recording, but the same thing also happens on some home movie tapes that were recorded with an RCA camcorder.

The second issue (Line running down picture.avi) is a line that starts at the top of the frame and runs down to the bottom. Whenever this happens I can actually hear a distinct noise from the VCR as the line runs through the frame. This is a recording from the RCA camcorder.

Both of these recordings are SP. In both cases it usually doesn't happen throughout the whole tape, just certain sections. I just bought a TGrant AG-1980 yesterday, as I have some LP tapes that don't play nicely on the JVC. Once it comes in I will test these tapes out on there as well.

Thanks in advance for your time/help.

[lordsmurf]

Timing error on a very small scale. Sometimes the ES10 can correct these, but other times that are of the video is simply too far gone, too much damage. I forget the technical jargon on this.

If the video booger is accompanied by audio boogers, it's physical damage, not just signal damage.

JVC VCRs can be worse with the width of the error, but it doesn't disappear on a Panasonic VCR.

It can be often be removed with the strong Avisynth script that is used to fight dropouts. See attached.

[sanlyn]

Yes, I've a few ornery tapes myself, and much worse. I doubt you can eliminate those ripples entirely. It's tape damage, or possibly was recorded that way in camera (the latter will be mostly irreparable, sad to say, but I've been there myself). One thing you can do is repack the tape(s). Repacking means fast-forward without playing from beginning to end, then fast rewind without playing. Do this a time or two until the packing in the takeup reel is relatively smooth and free of bumps and ridges. Let the tape rest for 24 to 48 hours. You might have to repeat the process. Repacking and resting can often allow tape's natural elasticity to repair itself.

Playing in a different VCR helps, too.

Meanwhile I used lordsmurf's .avs script, which has been getting some use lately so don't feel alone. The routine doesn't fix the ripples that much, but it smooths and thins them a bit. I added a few other tweaks, notably color work. The first sample has a green color cast and Rev. Jackson's hair is cyan. In sample 2 the dog is blue, ground details are grayed out, and red is blooming. Both have uneven borders and an offset image.The dog shot illustrates that the ATi 600 is clipping superblacks at y=16, as usual, but that can be worked around and you gave both captures good level control.

Sometimes color work can lend realism and dimension that distracts from other defects. If it's any comfort, I see a lot of defects in HDTV that engineers apparently didn't even try to tackle, not to mention illegal levels and horrible color. Below are two frames from each of the samples that I reworked in VirtualDub after running lordsmurf's script and a few other tweaks:

Sample 1, frame 112, original:


Sample 1, frame 112, reworked:


Sample 2, frame 50, original:


Sample 2, frame 50, reworked:


I can post details of the scripts and filters used if you want to pursue all that, but that will be later because the scripts are presently a complete, undecipherable mess
.

[msgohan]

I believe both are examples of the physical tape being creased / wrinkled / crinkled / pinched.

tapedamage_VHS.jpg
(image borrowed from https://psap.library.illinois.edu/ad...p/av-phonodisc)

Image showing wrinkle visible even when it's wound on the reel: http://www.digitalfaq.com/forum/vide...ideo-tape.html (That story had a happy ending BTW; someone else finally located another copy of the rare tape as part of an eBay lot of random items.)

Quote:

Originally Posted by skycaptain09

Whenever this happens I can actually hear a distinct noise from the VCR as the line runs through the frame.

If you eject the cassette at the right moment, you may be able to see the actual damage to the tape.

[lordsmurf]

Quote:

Originally Posted by sanlyn

Sample 2, frame 50, reworked:

That looks unnatural. Too much green, probably illegal red.

I know the point was removal of the lines, and in a still that seems to have worked. But, as usual, clips are needed. An error like this is pervasive, and stills can lie.

[sanlyn]

Well, I don't know. Color balance is pretty much a personal choice. Blue haired dogs and purple-gray dirt just don't seem to compute for me, even in overcast light.

[skycaptain09]

Quote:

Originally Posted by lordsmurf

It can be often be removed with the strong Avisynth script that is used to fight dropouts. See attached.

Thanks for the script! I tried running it but I don't have the clense function. I'm guessing I probably don't have some of the others as well, but I didn't make it very far in the script. Any idea where I can get these functions?

Quote:

Originally Posted by sanlyn

Repacking and resting can often allow tape's natural elasticity to repair itself.

I read in another thread to do this before capturing each tape, so I've been doing it once per tape. I'll try doing it a few times and let it sit and see if I can notice a difference.

Quote:

Originally Posted by sanlyn

I added a few other tweaks, notably color work. The first sample has a green color cast and Rev. Jackson's hair is cyan. In sample 2 the dog is blue, ground details are grayed out, and red is blooming. Both have uneven borders and an offset image.The dog shot illustrates that the ATi 600 is clipping superblacks at y=16, as usual, but that can be worked around and you gave both captures good level control.

Wow, with my untrained eyes I didn't notice the colors being off that much but your changes definitely look much better!

I originally was using a cheap Ion USB capture device but switched to the 600 after reading about it on here. I was amazed at how much better the ATI 600 captures looked; the Ion device washed out all of the colors. Are the missing ground details due to the 600 clipping blacks, or just the low resolution of the recoding? I've read about that in several other threads on here. After reading that the perfectionist in me thought about trying to get a capture setup with one of the AGP AIW cards using my parents' old Sony XP machine, but it isn't in great shape and the 600 is just easy to use.

The borders and offset image are how all of my tapes have been coming through. For the few that I've taken all the way to DVD I have just used AviSynth to crop the edges and then add borders to center it.

As for the level control, that's just a happy coincidence. I have been doing all of my captures with the AVT-8710 set at its defaults, as well as the proc amp settings in VirtualDub (other than setting the sharpness to 0 from the default of 2).

When you are making adjustments to videos like this, do you generally apply the same filters to the whole scene, or do you do different adjustments throughout the scene based on changes of what's in the frame?

Quote:

Originally Posted by sanlyn

I can post details of the scripts and filters used if you want to pursue all that, but that will be later because the scripts are presently a complete, undecipherable mess

I would certainly like to see the scripts when you have the time, but to be honest, I'm not sure how much effort I will be putting into color restoration just yet. My main goal is to get the best captures possible while I have good, working equipment and before the tapes get any older. I plan to keep the lossless captures archived so at some point in the future when I have more time I can put more effort into getting good colors. I know none of my family is going to notice that the colors are off; they're just going to be happy to see the videos, so that's my main focus.

I would like to make sure I'm getting the most detail out of the tapes, so if I can do that by adjusting settings on the 8710 to get colors in the proper range then I'd like to figure that out. What's your general approach to that? Do you try to find frames within a scene that have extremes and then adjust your levels based on that frame? I'm guessing once you find them you keep the same settings to capture a whole scene? I know you've discussed this in several other threads, so I'll go back and do some more research.

Thanks for the replies! Y'all are awesome!

[sanlyn]

Quote:

Originally Posted by skycaptain09

Thanks for the script! I tried running it but I don't have the clense function. I'm guessing I probably don't have some of the others as well, but I didn't make it very far in the script. Any idea where I can get these functions?

The clense function is in the RemoveGrain plugin. Current version is renamed RgTools. Actually, most people install both versions. They can co-exist together in the plugins folder.

Quote:

Originally Posted by skycaptain09

Are the missing ground details due to the 600 clipping blacks, or just the low resolution of the recoding?

No ground details were missing. They wee just the wrong colors. Improved contrast and color balance can often make an image look as if it has more detail. If details really were missing, they would be gone forever. You can't create detail from nothing.

Quote:

Originally Posted by skycaptain09

I've read about that in several other threads on here. After reading that the perfectionist in me thought about trying to get a capture setup with one of the AGP AIW cards using my parents' old Sony XP machine, but it isn't in great shape and the 600 is just easy to use.

The ATI 600 is perfectly adequate. As for the AIW's, they are visibly more accomplished but the differences are subtle and you would have an extremely difficult time seeing a difference without having made a great many captures and compared pixel for pixel. It doesn't take a hot system to run an AIW for capture, as they were designed for very early Pentium Win98 and Win2K machines, it's the later software that required XP.

Quote:

Originally Posted by skycaptain09

The borders and offset image are how all of my tapes have been coming through. For the few that I've taken all the way to DVD I have just used AviSynth to crop the edges and then add borders to center it.

Borders are seldom even and will differ in thickness with different players.

Quote:

Originally Posted by skycaptain09

As for the level control, that's just a happy coincidence. I have been doing all of my captures with the AVT-8710 set at its defaults, as well as the proc amp settings in VirtualDub (other than setting the sharpness to 0 from the default of 2).

VirtualDub's hook-in to the captue card's proc amp contyols are handy for setting legal video levels. You'd be amazed at the image problems from users who don't bother to set correct levels. It's not that difficult.

Quote:

Originally Posted by skycaptain09

When you are making adjustments to videos like this, do you generally apply the same filters to the whole scene, or do you do different adjustments throughout the scene based on changes of what's in the frame?

With Avisynth and Virtualdub you tend to collect a toolset of different filters. But seldom can two videos use the same filters or the same settings.

Quote:

Originally Posted by skycaptain09

I would like to make sure I'm getting the most detail out of the tapes, so if I can do that by adjusting settings on the 8710 to get colors in the proper range then I'd like to figure that out. What's your general approach to that? Do you try to find frames within a scene that have extremes and then adjust your levels based on that frame? I'm guessing once you find them you keep the same settings to capture a whole scene? I know you've discussed this in several other threads, so I'll go back and do some more research.

The only color control on the AVT8710 is Tint (or Hue). You have the same control in ATI's proc amp filters that you accessed thru VirtualDub capture.

Capture-time color correction with most analog sources is an exercise in futility. The color balance changes every minute, sometimes even within short movie sequences, and always with different shots in home video. Even retail VHS has color changes. if you stopped your capture to adjust for every color change, you'd never finish a capture. Post-process color filters are far more flexible and sophisticated. The exception for color correction during capture would be a tape that has obvious and severe color imbalance which could be resolved with a simple Hue adjustment and which would be constant for the entire tape. Not likely to happen.