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  #1  
07-17-2015, 11:00 AM
zimady zimady is offline
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Hi all.

I have acquired some old family VHS tapes which I would like to digitise. This is my first attempt at this so the learning curve is steep.

I have spent quite a lot of time browsing and reading various threads on this forum (a very impressive repository of knowledge). These have been particularly enlightening regarding the issues I am experiencing:
Tracking lines in video; how to fix these VHS tapes?
Help restoring dot crawl, dropouts, and grain on VHS videos?

However, I have reached a point where I think I need an expert to take a look at my results, particularly with regards the severe dropout artefacts I am getting.

My setup is as follows:
  • Panasonic NV-HS830 VCR
  • ClimaxDigital VCAP800 USB 2.0 Video Capture for Mac and Windows
  • Apple iMac
  • various VHS tapes ranging in age from 1985 to 2006

The problem:
Based on the highly detailed responses in the above threads by lordsmurf (I'm really hoping you'll dispense some of your sage advice in my direction!), I think my problem is an extreme case of magnetic dropout. I have 13 tapes with varying amounts of footage - all except 1 (referred to as Tape 5 from now) exhibit extreme dropout.

What I've done so far:
  • played the tapes through a smart TV - 12 of 13 tapes show severe dropout, Tape 5 shows almost no dropout
  • fast forwarded and rewound a couple of tapes all the way through - no change whatsoever
  • changed the tracking up and down - no improvement at all
  • played a number of tapes through the capture setup - results are consistent with the smart TV test (i.e. all but Tape 5 show severe dropout, Tape 5 is fine)
  • tried capturing short sequences - dropout is captured as seen on smart TV and preview, Tape 5 captures fine

My conclusions so far:
  1. I strongly suspect this is due to the age of the tapes.
  2. I suspect not much can be done other than some post-capture software filtering, and even that is not likely to help much given the amount of dropout I am getting.
  3. I don't think this is a problem with the VCR (because it plays one tape without any problems)

A couple of other points to note:
  • Audio quality is good for all videos, both in playback and capture. Without exception.
  • In the affected videos, the dropout is present to the same degree throughout the footage (not just at the start).
  • If I pause the video, picture quality improves dramatically (almost no dropout apparent). I can capture decent quality single frames from paused video).

My questions:
  • Is this magnetic dropout? If not, what is it and what is the likely cause?
  • Is it worth trying the tapes in a different VCR(s)?
  • Given the dramatic improvement in quality of paused video, is there any way I can take advantage of this to capture decent quality video? (with hours of footage, it is not viable to manually pause and capture every frame!)
  • Given the severity of the problem, and if improvement may be made through hardware/software, is the level of improvement I can expect to get worth the time and effort (and cost)? Should I just accept that time has taken its toll and get on with digitising them as is?
  • Anything else I should know/consider?

Finally, the samples:
  • dropout-sample.mp4 - this is representative of the worst tapes. A few are slightly, but negligibly, better (audio removed)
  • snapshot-during-playback.jpg - a still showing a representative sample of dropout
  • snapshot-when-paused.jpg - a still capture when the video is paused. Much improved!

Apologies for the long post - I've tried to anticipate the obvious questions so I don't waste others' time. Thanks in advance for any help/guidance/advice.


Attached Images
File Type: jpg snapshot-during-playback.jpg (118.4 KB, 29 downloads)
File Type: jpg snapshot-when-paused.jpg (87.6 KB, 23 downloads)
Attached Files
File Type: mp4 dropout-sample.mp4 (5.12 MB, 23 downloads)
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  #2  
07-17-2015, 11:23 AM
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Goldwingfahrer Goldwingfahrer is offline
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Other setter select.
Teststream in Lagarith encode and then do not encode so here high-level store...... like the example in MPEG-4 Visual.
MPEG-4 Visual [DivX / Xvid] is suitable old as the hills and qualitatively for original analogous not or only in the rarest cases with very high bit rates.

Only if the films are restored in mpeg4 encode if one wants goes also in interlaced, so not only in progressively.

Were the films from cameras on a recorder covered up at that time and put because on VHS-ET?

If you can want you to me a tape send, then then I select the best setter from my collection. England is almost beside us on the map of the world
---------------------------------
Old=
ITU-T H.263 / MPEG-4 ASP Video: DivX, Xvid, Adobe Flash

topically
ITU-T H.264 / MPEG-4 AVC Video: x264, Hybrid,Apple QuickTime, Nero Digital, MainConcept H.264/AVC
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  #3  
07-17-2015, 10:35 PM
msgohan msgohan is offline
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Doesn't look like dropouts to me. Looks more like an S-VHS tape played in a VHS machine (but your VCR is S-VHS, so presumably that isn't it).

Your sample is interlaced but encoded in progressive mode, which makes things slightly difficult. But one thing is still clear when deinterlacing is applied: every bottom field is "okay" (still bad), while every top field is completely screwed up. This is likely why it looks "okay" when you pause: only one field is being displayed.

Deinterlaced, here is field 38 and the very next field. With the VCR connected to your TV, you should see the image rapidly flashing like this. (The red arrows point to what I would call an actual dropout line.)
Zimady-Bad-Bobbed-field38.jpg
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Assuming the tape was recorded correctly in the first place, it seems one of your VCR's playback heads is faulty.

BTW, your video is PAL but is inexplicably encoded at 30fps with duplicates instead of 25fps.


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  #4  
07-18-2015, 04:44 AM
zimady zimady is offline
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Thanks Goldwingfahrer and msgohan.

msgohan, I have tweaked a few settings to correct the frame rate and interlacing. Is the attached sample less "difficult" to diagnose? (I want to remove as many variables as possible).

Quote:
Assuming the tape was recorded correctly in the first place, it seems one of your VCR's playback heads is faulty.
If that's the case, why would one tape play OK? I'm not questioning your diagnosis, just seeking to understand this better.

Your diagnosis has given me hope that, with the help of the expertise on this forum, there may be a way to rectify this issue and get some decent quality video from the tapes. On that basis, I'm going to try and source another VCR to try, and I'm also going to drop the $20 on premium membership to get the best support I can!

Thanks so far.


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File Type: mp4 Interlace and framerat_0017.mp4 (6.18 MB, 8 downloads)
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  #5  
07-18-2015, 05:43 AM
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Goldwingfahrer Goldwingfahrer is offline
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Quote:
and I'm also going to drop the $20 on premium membership to get the best support I can!
Yes, so I have also made this although I am able nobody in English, everything must translate.
But to learn I am never too old.

Completely wrong gecapturt. See picture 1

Thus it should look, indicated in media info [free of charge]..... Picture 2


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File Type: jpg 1.jpg (52.1 KB, 16 downloads)
File Type: jpg 2.jpg (47.1 KB, 9 downloads)
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  #6  
07-18-2015, 08:44 AM
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Quote:
Originally Posted by zimady View Post
If that's the case, why would one tape play OK? I'm not questioning your diagnosis, just seeking to understand this better.
The diagnosis-hypothesis is sound. The reason is because the tape itself can cause odd interactions. You simply need to try the tape on another player, and see how it fairs.

Quote:
Originally Posted by zimady View Post
I'm also going to drop the $20 on premium membership to get the best support I can!
We're here to help.

- Did my advice help you? Then become a Premium Member and support this site.
- For sale in the marketplace: TBCs, workflows, capture cards, VCRs
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  #7  
07-18-2015, 09:02 AM
msgohan msgohan is offline
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Quote:
Originally Posted by zimady View Post
Is the attached sample less "difficult" to diagnose? (I want to remove as many variables as possible).
The new one is still encoded as progressive, but don't worry about it. My thoughts would remain the same regardless.

Quote:
If that's the case, why would one tape play OK?
Well, first I have to wonder whether that tape actually plays well, or if it plays the same as the "decent" paused image that is still flawed.

Then my other thought is that perhaps this one tape is recorded in a different mode than the others (SP vs LP, or maybe VHS vs S-VHS even).
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  #8  
07-18-2015, 09:28 AM
zimady zimady is offline
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Goldwingfahrer - thanks, I now have MediaInfo. Very useful!

I think the problem with the encoding is down to the software I'm using which shipped with USB 2.0 capture device I'm using - VideoGlide: https://www.echofx.com/videoglide.html. The 'Capture' module seems to provide a decent level of control over the codec but only seems to capture to .mov format. I've been using the accompanying 'Exporter' module to convert it to a more web friendly format (MP4) but that provides very limited control over the codec and uses a different codec to the original .mov file.

Any suggestions for:
  1. What codec I should be using at the capture stage?
  2. Recommendations for tools to quickly convert from one one format to another (on OS X)?

Finally, I've sourced another VCR (maybe 2) from my mother-in-law which I'll be collecting in a couple of hours so more tests coming soon!
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07-18-2015, 02:45 PM
msgohan msgohan is offline
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I've seen people mention QuickTime Animation as a lossless codec on Mac that is well-supoorted. It will be preferable to capturing to a lossy format, if your capture software or another software allows it.

Glad to hear you were able to get another VCR for tests without having to buy one.
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  #10  
07-19-2015, 06:43 AM
zimady zimady is offline
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Success - the hypothesis, diagnosis and prognosis where all correct!

I wasn't able to use my in-law's VCR as I don't have the necessary adaptors to connect its outputs to the capture device. However, my in-law's neighbour lent me a Sharp 6 head VCR and that is working a treat. The quality of footage I am getting now is much better than I'd initially hoped for!

I also remembered that I have a license for Apple's video editing suite (Final Cut Pro X, Compressor and Motion) from when I worked for Apple so I tried transcoding the captured footage using Compressor and am getting great results.

So I'm now going through the time consuming process of digitising 13 videos. I will then transcode them to MP4 for archiving. I also propose to edit all the best bits into a single, shorter movie with captions, titles and perhaps a soundtrack and I may also author a DVD with chapters to make it easy to access and play specific sequences/events.

Since I will be editing the footage, I have chosen to capture using the DV PAL codec (Quicktime Animation is not available). This gives me the best quality capture of all of my options and I understand it uses intraframe compression which is better for editing than interframe (correct?).

Please feel free to add and recommendations, tips, cautions at this point!

Thank you msgohan, lordmsurf, and Goldwingfahrer for your help. I can't say enough how grateful I am for your help in getting some good quality digital versions of these old family videos. They will be treasured by myself and my family.
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  #11  
07-19-2015, 09:39 AM
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Quote:
I will then transcode them to MP4 for archiving.
To Mac I can write nothing, I do not use something like that.

However, I would concern before the first film in the MP4-Kontainer it is provided me around a very good tool MP4.

I am already present since the first version and am contented.
Selur writes also in the German Doom9 forum

http://forum.doom9.org/showthread.php?t=153035

http://www.videohelp.com/software/Hybrid


Quote:
I have chosen to capture using the DV PAL codec
Here Capturen of analogous in DV-Pal we make only if a customer this absolutely wants.
They do not notice, perhaps, at all that there a lot it is thrown away and in sloping edges colour hemlines are to be seen.
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  #12  
07-19-2015, 11:07 AM
msgohan msgohan is offline
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Quote:
Originally Posted by zimady View Post
I will then transcode them to MP4 for archiving.

...

I have chosen to capture using the DV PAL codec (Quicktime Animation is not available).
The manual I found for your product shows an "iGrabber" software rather than VideoGlide, but looking at a Diamond Multimedia manual that shows VideoGlide, they appear to be the same thing with a different name. Here is the VideoGlide compression menu showing "Animation" at the top. If there is a setting for Quality, it needs to be set at 100% for lossless mode. Otherwise you're better off using a different codec.

VideoGlide - Compression Menu.PNG

"YUV422" is uncompressed: the same quality as lossless, but much larger. "None" is uncompressed, but it may be converted to RGB which would be bad.

If you're going to capture to DV, archive the DV captures IMO. If these are full 2-hour tapes, 13 of them stored as DV would be 13 * 2 hr * ~13 GB/hr = ~338GB. A 1TB portable drive can be had for very cheap these days.

Quote:
I understand it uses intraframe compression which is better for editing than interframe (correct?).
In terms of speed/ease, yes. Interframe compression at the same bitrate, like 25Mbps MPEG-2, could potentially yield better quality.


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