Industry VHS protection frustration

[Geoffrey Cox]

Hi,

I've searched the forum here but found no solution to this: I'm trying to copy a VHS tape to DVD but it is copy protected (in case you're wondering, the VHS is long deleted, and no DVD version available, and I'm copying for a friend who also bought it originally but his copy is broken). Is there any way round this? I've tried the following methods all of which failed:

1. Straight from VHS to DVD recorder via SCART - warning screen appears
2. From VHS into TV, out of TV into DVD recorder (all SCART) - warning screen appears
3. From VHS into Matrox MXO2 Mini (SCART - SVideo converter) streaming into FCP - no warning screen but image distorted (non protected tapes work fine)

I gave up at this point! I find all this frustrating as we both paid for the tapes, one is now worn out and I just want a working, durable copy for my friend, which seems perfectly legitimate to me.

Anyone know of any solutions which don't involve expensive hardware / software?

Thanks.

Geoff

[R Geoff Baker]

The warning screen confuses me -- I don't see how an analog tape can carry an embedded screen, and what could trigger it -- what does it say?

The typical tape copy protection system involved making some part of the signal so weak as to make a copy unlikely, unless you had an amplifier that was able to boost the control track, or the chroma subcarrier, or whatever was weak in that method. There were any number of $100 boosters back in the day, and generally they worked.

But this business of a screen confuses me ..?

Cheers,
GB

[Geoffrey Cox]

Thanks for the response Geoff. It says 'You are not allowed to copy this recording. Error E51'. Maybe it triggers it in the VCR (JVC)?

I tried a 4th method - connecting the VCR into a mini DV recorder and didn't get any warning screen this time, or distorted signal but no signal at all once I pressed play on the tape (again a non-protected tape works fine).

At a loss really - they've really sown this one up it seems. Maybe I could try another VCR if I can find one...

[R Geoff Baker]

It makes sense that the message is from the recording VCR, not the tape being copied.

IIRC there were some VCRs that were designed to identify Macrovision (a particular and popular copy protection system), and block recording of a Macrovision protected signal. Which suggests a couple of possibilities:
- use as a recorder something that doesn't identify Macrovision ... in the past I used my PD170 DVCam camera to record via the analog inputs, I doubt that I ever tried a commercial tape but the point is it was unlikely to have a Macrovision detection capability;
- run the signal from the source deck through a timebase corrector ... I think that was the area of the signal Macrovision monkeyed with, the vertical sync pulse, and so the TBC should be able to restore it;

Hope that helps.

Cheers,
GB

[Geoffrey Cox]

Cheers Geoff, will try what you suggest with a different VCR and /or DV camera (though I suspect the latter won't work given all the various recording devices I have tried including a mini DV/HDV recorder a (Sony HDV700) and Matrox hardware).

Btw when I said the VCR was detecting it, I meant the player not the recorder as whatever device I try and record on, it seems the VCR is sending something out that non of the devices like - surely they can't all be wise to Macrovision?

One question - what's a timebase corrector - is it something I could easily use / obtain?

Btw when using methods 1 and 2 below the image does appear momentarily but is replaced quickly by the warning message.

[R Geoff Baker]

You'll find Macrovision -- if that is the problem -- was only used in consumer devices, so if you have access to professional equipment it won't have any Macrovision awareness. That's a start, but a Macrovision encoded tape will have sync pulse issues on any device that play it; the sync pulse was intentionally recorded at the minimum useful level, and so a copy resulted in enough loss to make the signal unusable. The picture would typically 'roll', as the vertical sync wouldn't lock, or 'skew', for essentially the same reason.

Timebase correctors, or TBC, were devices used in the analog era to restore the exact timing of the frames. Analog tape was always prone to wow and flutter, and in the analog era that would create miniscule timing differences in the frame playback. Typically, this would manifest as a waving vertical lines -- at its worst, everyone looked like they were shaking side to side. Well, not quite worst -- vertical roll would be the result if things were really bad. So a TBC had a frame buffer, and would take the input from the analog signal, wait until it had the full frame, then release it but with a new, restored and mathematically perfect line timing.

TBC were standard issue for any professional dub house or edit facility, and eventually even mid-range pro decks had built in timebase correctors. Once we moved to digital recordings, the need for TBC vanished as all digital formats, by their nature, have perfect timebase. So any digital tape format, or any DVD, even when playing back through analog outputs, has a timebase exactly as good as one created by a TBC.

I suspect you are seeing the warning after a brief playback of the signal because the deck takes a second to recognize the issue. I don't see how it is possible for the playback deck to be the culprit, as analog connections are one-way only and there is no possibility of a returning signal to the player -- we didn't have that sort of 'handshake' capability until HDMI type connections became standard. That said, I guess anything is possible ... but my suggestion is that it's highly unlikely that an analog player can ever know what is happening to or where the signal is going once it leaves the deck.

Cheers,
GB

[Geoffrey Cox]

Thanks Geoff - really useful info.

I don't think I'll be able to source a pro VCR or TBC so it may be the end of the road; all the recording devices I've tried have been via analogue inputs (SCART, Composite and SVideo) so can't see what else to try except perhaps an older DV camera which I can access, as you suggest, but not sure why this would be different.

Geoff

[R Geoff Baker]

Note that all my comments have been 'theoretical', in that I've never had to make a copy of a Macrovision protected tape ... years ago I owned a chain of video rental stores, and so had to be familiar with the protection schemes and how they impacted rental playback (Macrovision encoded tapes wore out faster than none, and would become unplayable much quicker) -- since I moved into the world of production, I've had limited exposure to copy protection schemes.

That said, a google search for 'defeat VHS Macrovision' or some such is likely to turn up some useful posts from those that have actually had to get it done. There may well be solutions that are achievable with gear you can access.

Cheers,
GB

[David Heath]

Have a look at Rovi Corporation - Wikipedia, the free encyclopedia for a good overview of Macrovision.

Macrovision's legacy analog copy protection (ACP) works by implanting a series of excessive voltage pulses within the offscreen VBI lines of video. These pulses are included physically within pre-existing recordings on VHS, and generated upon playback by a chip in DVD players and digital cable/satellite boxes. A DVD recorder receiving an analog signal featuring these pulses will detect them and display a message saying that the source is "copy-protected", followed by aborting the recording. VCRs, in turn, will react to these excessive voltage pulses by compensating with their automatic gain control circuitry, causing the recorded picture to wildly change brightness, rendering it unwatchable.[citation needed] The system was only effective on VHS machines. The other home-video format around at the time Betamax, used its AGC in a different manner and was immune to Macrovision protection.[12]

On most televisions, these pulses cause no visible effects because their automatic gain control circuitry, unlike AGC circuits within VCRs, is purposely engineered to not react to them. Very old televisions, however, would react to them, producing distorted images as a result. On some TVs that do not properly blank the vertical retrace, dotted white lines additionally appear near the top of the picture. Some newer TVs also mistake the Macrovision pulses for synchronization pulses.

[Lee Mullen]

Try using a Canopus ADVC 110 and connect a VCR to it then the firewire to the computer. Works for me.

[Bruce Foreman]

Geoffrey,

Info in this thread should help you. Look for posts by Kaxmir.

HOW do I copy MY Video (store bought) tape to a DVD? - AfterDawn: Forums

I had a similar device back when all we had was VHS. I never used it to copy rental tapes, but to make a copy of tapes I'd purchased so I could put the "wear 'n tear" of watching on something other than the original which I'd store on a shelf.

The device I had seemed to work very well.

[Geoffrey Cox]

Originally Posted by R Geoff Baker

You'll find Macrovision -- if that is the problem --
GB

Thought I'd update the thread and thank all posters too. And let this be a cautionary tale. After somehow getting hold of a pro VCR with TBC and still getting the same problems I began to question my sanity, until I noticed that the TBC function disabled itself whenever I put the tape in. Why? Downloaded the VCR manual and in small print in a footnote it says the function does not work with NTSC tapes. Doh!!! Flashes of angst / revelation etc etc. It's an NTSC tape! I bought it from the States!! Quickly changed all the capture settings to NTSC and suddenly all is fine, except it's all in B&W and a bit of quick research reveals this is not easy to overcome (it's a bastardised form of PAL that the VCR uses to play back NTCS tapes and can't be properly encoded by the capture hardware alone).

So I'm kind of back to square one (and of course Macrovsion could still be in operation here too). Can't get an NTSC VCR, not going to pay for an expensive transcoder, don't want B&W (!). What's left? Filming it off the screen with a camcorder. I'm not joking.

Apologies for wasting everyone's time :(

[Chris Soucy]

Hi, Geoffrey..............

Reading your last post triggered a long forgotten tit bit I'd seen somewhere else, so I went and dug out the manual for our top of the line Panasonic VCR we brought over from the UK some years ago (still doing sterling service, must be 12 years old at least!).

Yep, sure enough on page whatever, there it was about playing back NTSC in colour on a telly but other VCR's not being able to capture in colour because it's a bastard PAL signal.

So, it has occured to me, what if you feed that video signal to the video in on a digital SD camcorder?

Do you get colour or not? Might work, might not, worth a try. Got a Canon XL 1s or similar lying around?


CS

[Geoffrey Cox]

Hi Chris,

Thanks for the suggestion.

Yes somewhere in this process I did think about this. It doesn't work with the Sony deck and Canon camcorders I've tried but these were all HDV types set to SD mode (no image at all, let alone B&W). But maybe a native SD camera could work? I can borrow an XM2 so will try it...

Geoff

[R Geoff Baker]

When last I lived in the UK it wasn't too hard to find NTSC vhs players, and I mean the real deal, not NTSC-to-PAL hybrids. Find one, attach it to one of any of the many analog to digital convertors and Bob's your uncle.

Once you have a digital file on your HDD you can work at converting it to PAL if you want ... ohh, and I hope Macrovision doesn't raise its head ...

Ya sure it's worth all this effort ..?

Cheers,
GB