Is This Macrovision Protection?

[Jason Dunn]

I have nearly 100 VHS movies, and I'd like to archive some of them to DVD for long-term use. When I read about George Lucas yet again fiddling with the original versions just about to be released onto DVD, I knew it was time for me to archive my original, non-special edition Star Wars box set onto DVD. I hooked up my VHS player to an <a href="http://www.adstech.com/products/API_550/intro/api550intro.asp?pid=API-550">ADS Pyro A/V Link</a>, and using <a href="http://www.pinnaclesys.com/ProductPage_n.asp?Product_ID=1501&Langue_ID=7">Pinnacle Studio 9</a>, I recorded the whole tape to a DV-AVI. Everything worked perfectly - I didn't have a single dropped frame! :D The ADS Pyro A/V Link really shone - it was amazingly simple to set up and use (more on that later). I used Pinnacle Studio 9 to colour-correct the video and adjust the contrast a little, making for a very nice looking final image source...sort of.<br /><br />The problem is that the resulting AVI file "flickers". I've created a <a href="http://www.digitalmediathoughts.com/files/sample.avi">10 second clip that's 35 MB in size</a> so you can see for yourself what I mean. This flickering happens with the original AVI file, prior to any corrections from Pinnacle Studio 9. The question is, is this flickering normal, or is it the Macrovision protection kicking in? I don't think the ADS Pyro A/V Link has the ability to bypass Macrovision copy protection, so I'm unsure if this is "normal". Anyone have any input?

[sub_tex]

I don't think it is macrovision. I remember years back a friend trying to record vhs to vhs and the protection on those would make the video go very dark and squigly/messed up looking every 10 seconds or so. It did wobble like this, but the brightness/sharpness going back and forth like a wave every 10 seconds was the worst.

I'm assuming that was what macrovision does. Perhaps a problem in the connection? Interference?

[Jason Dunn]

I don't think it is macrovision. I remember years back a friend trying to record vhs to vhs and the protection on those would make the video go very dark and squigly/messed up looking every 10 seconds or so. It did wobble like this, but the brightness/sharpness going back and forth like a wave every 10 seconds was the worst.

Yeah, the Macrovision I've seen is much harsher, but I can't figure out what's causing this flickering.

[Tim Williamson]

Maybe it's the Flickervision protection kicking in... :wink:

[Doug Johnson]

That looks like a normal VHS unstable signal. Macrovision would be much more annoying, causing a rolling picture, or phasing in and out of color or color accuracy.

To get rid of what you are seeing you need a time base corrector, or VCR with a digital signal processor. You might be able to get away with a software stabilizer, but hardware solutions do a better job.

[EscapePod]

For what its worth, it looked perfect at 320 X 240 !

[Mojo Jojo]

The strange thing about macrovision is that it behaves differently on different vcr's depending on how the VCR is made and when it is made.

Macrovision exploits the automatic gain control (AGC) circuit in the recorder. The purpose of the AGC is to adjust the level of the video signal in such a way that the recording capabilities of the tape are fully used. This means that weak signals are amplified and strong ones are attenuated.

In the Macrovision method, some new signals are inserted in the non-visible portion of the picture. These signals can make the VCR think that a perfectly normal picture is suddenly way, way too bright. The AGC circuit therefore darkens it until it thinks the brightness is normal. Of course, now the REAL picture is very dark. The picture is varied between bright and dark periodically in order to defeat simple eliminators that would just amplify the dark and murky signal back to almost normal.

The proper behaviour of the AGC-circuit is very important in order to achieve good protection. Apparently the specifications were somewhat "loose" in the pre-Macrovision days, so the old (how old?) machines are not affected.

JVC, the VHS license holder, has tightened the spec and the control, so it is difficult to get an "immune" VCR, but there are some machines that are conveniently "out of spec".

I imagine what your seeing *is* macrovision, just your vcr isn't effected that much. You can tell it is having some effect by the wobbling at the extremes of the viewable area.

[Jason Dunn]

That looks like a normal VHS unstable signal.

I don't see the same flicker when I watch the VHS tape though - or is this just something that shows up when the signal is converted to digital?

You might be able to get away with a software stabilizer, but hardware solutions do a better job.

There IS a software stablization plugin as part of Pinnacle Studio 9, so perhaps I'll give that a try...but I think it's more for camera jitter.

[Jason Dunn]

For what its worth, it looked perfect at 320 X 240 !

Unfortunately I need it to be at 720 x 480 to burn a DVD, so that won't quite help me. ;-)

[Doug Johnson]

I don't see the same flicker when I watch the VHS tape though - or is this just something that shows up when the signal is converted to digital?

Pretty much... I have noticed that Analog TVs handle an unstable signal better than digital does.

Have you tried adjusting the tracking to see if it gets any better?

I was having a similar problem with my tapes (not digitizing, but viewing them on a DLP projector), and I got a JVC HR-S9900U VCR that does a great job of cleaning up the signal. It doesn't just fix the jumpiness, either; it actually removed a bunch of noise and fixed the color a bit too. It was kind of pricey, but maybe you could find one on eBay for cheap. Copy your tapes, then put it back up for sale so someone else can do the same. (The successor is the HR-S9911U, which is probably easier to find)

Would you like me to put together a quick demo so you can see the difference?

[Fitch]

Looks like it may be Macrovision. I went and looked this up
http://electronics.howstuffworks.com/question313.htm
So if there's extra data during that blanking interval, then you'd probably get a pulsing-kind of look.

[backpackerx]

Could it just be normal interlacing? Isn't all video for analog TV interlaced and then you see it during progressive digital playback?

[Jason Dunn]

Could it just be normal interlacing? Isn't all video for analog TV interlaced and then you see it during progressive digital playback?

Nah, interlacing looks different, and besides, it unfortunately looks the same when I burn it to DVD and watch it on a TV set...in fact, that flickering is worse.

[Suhit Gupta]

For what its worth, it looked perfect at 320 X 240 !
Same here, but at 100% video size, which is larger, there is clearly some flickering.

Suhit

[Suhit Gupta]

Yeah, it either looks like regular interlacing (though I may be a bad person to be commenting on this because of my ridiculously bad TV) or may just be VHS. Most videos I have seen end up looking something like that, though the "flickering" is unusually high here. Jason, are you sure this isn't becasuse your tape quality has degraded by too many viewings? I mean, have you tried the conversion process on some other VHS tape?

Suhit

[ux4484]

Luckily, I have the first three in their original versions on Laserdisc (no Macrovision). I burned them to DVD via my rack burner (DVD+R) and have sinced ripped them to my external hard drive for archival purposes.

:D

[jspear]

Luckily, I have the first three in their original versions on Laserdisc (no Macrovision). I burned them to DVD via my rack burner (DVD+R) and have sinced ripped them to my external hard drive for archival purposes.

:D


You just want to make everyone drool and wish they could say 'do you have a bittorrent share?'/ 8)

[ux4484]

You just want to make everyone drool and wish they could say 'do you have a bittorrent share?'/ 8)

heh...I would never participate in such a venture...

I lucked into the LD's. One of my buds bought his night school's teachers LD collection(for a song) which included two sets of the original SW LD's, he shared the second with me :D .