Digitising VHS Tapes: Part 1(3) – Digitising Process Considerations


I came across a box of VHS tapes recently that had been in storage for several years. Feeling nostalgic, I hooked up my top-of-the-line Samsung SV-4000W VCR and put in a tape to watch. The tape was promptly chewed up. My VCR had suffered a catastrophic mechanical fault in the tape transport mechanism. So I got online to look to first repair or replace my unit with a newer and more recent model. To my shock and horror, I realised that you could no longer buy a new VCR. I wasn’t keen on picking up a secondhand unit on e-Bay as it was going to be a bit of a lottery picking up a unit that did not suffer from mechanical issues given the vintage of these units.

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Fortunately, I had a backup VCR a Panasonic NV-FJ620 that still worked. It dawned on me though that once that failed, I wouldn’t be able to view any VHS footage easily. Time to digitise those VHS tapes I thought and have the digitised files accessible in a Plex library.

Panasonic-NV-SJ200-VCR-VHS-Player-Super-Drive.jpg

The first thing to do prior to playing tapes that have not been used for some time is to re-tension the tape by fast forwarding to the end and then rewinding back to the beginning of the tape. Do this at least once. This helps the tape to move freely during video capture.

Video Capture

I had a Canopus ADVC-50 unit that I could use to convert analogue footage to digital. So I set that up, but, with age, it too had failed. Nothing I did could correct a vertical roll of the image. I suspected damage to the electronics. As I hadn’t stored it carefully, I’d probably zapped the circuitry from an electrostatic discharge at some point.

Note that the Canopus units deliver a digital format over FireWire technology. A FireWire card has to be installed in a desktop PC to receive the output from the ADVC-50. Fortunately, I had a FireWire PCI card that worked. Point to note though is that many modern motherboards no longer support PCI. Fortunately, I had a fairly recent motherboard that did. Also, note that there was a time when laptops were built with FireWire capability, but modern laptops are no longer supplied with this functionality. FireWire is considered a bygone technology, being replaced with ubiquitous USB technology. Refer to the article FireWire versus USB for more information. For the popular, but now defunct Canopus units, which produce a FireWire output, this spells a limited life for them. Canopus, PCI, FireWire, VHS, VCR are all on different points of a journey to a more rarefied stratosphere.

OLYMPUS DIGITAL CAMERA

Next stop, off to a local Jaycar store to see what they might have for converting analogue footage to a digital format. I found the KWoRLD DVD Maker 2, which delivers a digital format using USB 2.0 technology.

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It also comes with a version of Cyberlink PowerDirector for video production. Not as powerful or sophisticated as the Adobe suite of video editing tools I believe, but, after tinkering with it for a while, found it sufficient for what I wanted it to do. It was good enough for me to consider investing in an upgrade to a current software release.  Note that my video editing experience is at a novice level.

I was now ready to start converting my VHS tapes, or so I thought. Here is a still frame from the digital output of the DVD Maker 2.

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Notice the ‘combing effect’, which is very apparent on the white areas, but, on closer inspection, is prevalent everywhere. The issue is one of interlacing. This is explained very well in the YouTube video The Interlaced Video Problem – Computerphile. It can be corrected by software like VLC. How you do this is explained in the article How To Fix Video Interlacing in Your Movie Files On the Fly. However, it is better not to have the issue in the source file. What to try next?

I thought the issue might be the output of the DVD Maker 2. My Canopus unit was busted so I couldn’t confirm this. It turns out one of my brothers was in possession of a Canopus ADVC-100, which I borrowed to test my theory.

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Here’s the output of the same frame, but from the ADVC-100.

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The ADVC-100 does a better job of dealing with the interlacing issue in hardware.

Time Base Correction

While the ADVC-100 addresses the interlacing issue, it still suffers from several problems:

  1. Touched upon already, it uses outgoing FireWire technology. Not a biggie, but still something to be aware of.
  2. Video capture aborts in Cyberlink PowerDirector software if a ‘noisy’ captured signal is interpreted as macrovision copy protection. Refer to the Cyberlink article  Copyright material error unresolved! Please help. for more information on this.
  3. A manual dip switch setting is used to select between NTSC or PAL analogue input. As the tapes I own use one or the other, it became a nuisance to manually change the settings for the tape currently being digitised. An endearing feature of the DVD Maker 2 is that it can accommodate both NTSC and PAL analogue input signals without manual intervention.
  4. The biggest issue of the ADVC-100 is that it does not address mild ‘warping’ of an image arising from horizontal jitter. To understand what this is, have a look at the left and right edges of the following image.

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Notice the kinks in the vertical line. This is the result of horizontal jitter. The Canopus products do not address this. The effect of this jitter is a softening and distortion of the image. For a more technical explanation of the issue of a corrupted time base, have a look at the article Analog video time base correction and processing for nonstandard TV signals. For an excellent, easy to read explanation of time base correction, have a look at  TBC Trivia. For an overview and comparison of different sorts of time base correctors , check out What is a TBC? Time Base Correction for Videotapes.

Where to next? I purchased an AVToolBox AVT-8710 time base corrector (TBC) from the US on Amazon. It cost me around AUS$300 including shipping.

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The AVT-8710 is placed in the video path between the VCR and ADVC-100. Here’s the same image as above, but with time base correction.

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Notice how left and right edges of the image are a lot straighter. This will also result in a sharper image overall. To appreciate this, have a look at the bump on the top left of the previous image of the dolphins and follow that through to the top centre of the image where the fence rail meets the sky. Compare it with the rail in this image, which appears to be much straighter. Note that the AVT-8710 wasn’t able to entirely eliminate the more severe curl at the top of the image or correct the distortion at the bottom of the image, but I was happy to accept that.

The marriage of the AVT-8710 and ADVC-100 product was not a happy one though. I experienced random ghosting issues, usually at the beginning of a tape. See the image below. I’m still not sure what caused this.

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Repeating this exercise with the DVD Maker 2 without the TBC yielded the following image.

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The image suffers from both the interlacing and horizontal jitter issues. With the TBC included, the horizontal jitter is eliminated, but the interlacing issue persists as seen in the image below.

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The ghosting issue seen with the TBC and Canopus hardware combination did not appear with this combination of hardware. We’re still left with the interlacing issue though.

Video Editing

The Cyberlink software does a pretty good job of de-interlacing. The image below is de-interlaced and has had the lighting adjusted.

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Summary

It turns out that the best results I was able to achieve for capturing VHS footage used a combination of the AVT-8710 TBC and DVD Maker 2 hardware and Cyberlink PowerDirector software. The AVT-8710 addressed the horizontal jitter in the analogue signal from the VCR to provide as clean a signal as possible as input to the DVD Maker 2. The old adage ‘garbage in, garbage out’ applies here. A corollary of this is that subsequent clean digital signal out of the DVD Maker 2 resulted in the elimination of noise that might have been interpreted as macrovision protection by the Cyberlink PowerDirector software. PowerDirector was used for video capture, de-interlacing, lighting correction and creation of MPEG-4 video.

Why MPEG-4 (H264 codec) and not MPEG-2? Very simply, think MPEG-2, think DVD; think MPEG-4, think internet. For an excellent explanation of the history of various MPEG codecs refer to  Understanding MPEG-2, MPEG-4, H.264, AVCHD and H.265.

The final image below of the dancers (with Rebecca Allen in the forefront) was produced using the hardware and software combination described above to capture analogue VHS footage and digitise it as MP4 files.

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In Part 2 of this series, I attempt a repair on my failed Samsung VCR.

Edit: Check out these postings as well for other relevant topics.

  1. Digitising VHS Tapes: Part 1(3) – Digitising Process Considerations
  2. Digitising VHS Tapes: Part 2(3) – Samsung Worldwide VCR SV-4000W Repair
  3. Digitising VHS Tapes: Part 3(3) – Digitising Process Refinements
  4. A Bypass Switch for the Time Base Corrector

References

  1. What is a TBC? Time Base Correction for Videotapes
  2. The Interlaced Video Problem – Computerphile
  3. TBC Trivia
  4. How To Fix Video Interlacing in Your Movie Files On the Fly
  5. FireWire versus USB
  6. Copyright material error unresolved! Please help.
  7. Analog video time base correction and processing for nonstandard TV signals
  8. Understanding MPEG-2, MPEG-4, H.264, AVCHD and H.265

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