Macrovision causing problems!

[1100 man]

I've never had any need to get involved with Macrovision copy protection up till now. On the rare occasions I've ever watched a DVD in the past it's always been on a TV with a scart socket.
I have a Thorn 1500 which I use with a 3V29 to watch vintage video's from time to time. I have a DVD player connected to the video I/P of the 3v29. The few things I have played up to now have been fine. Playing a DVD tonight, I was greeted with varying contrast which went from min to max regularly over the course of a few seconds. After some head scratching, I concluded it must be macrovision causing the problem.
I remember many years ago looking at a video waveform on a 'scope and seeing the Macrovision pulses changing in amplitude on an otherwise stable signal.

Having searched the forum, there are several old threads on the subject. It would appear that Darius had developed a unit that would clean up a video signal (The UVB) http://bs.cyty.com/menschen/e-etzold.../uvb/uvb_e.htm

I got the impression that this did not remove the Macrovision but could help reduce the effects of it. Does anyone have any experience of this unit and is it still available?
There must be other members who use DVD players with vintage TV's- how do you get round the problem?
Trying several different disks from my meagre collection, some played fine and some had copy protection.
Many thanks
Nick

[winston_1]

The simplest way is not to connect it via a VCR. Use a UHF modulator instead.

[ben]

I'd just get an RF modulator off an old playstation or video camera instead of going through the video. That wouldn't be affected by the macrovision pulses.

Or a DVD player with a USB input to allow you to play 'cleaned up' versions of the material directly from a file.

[julie_m]

Some DVD recorders could be persuaded to ignore Macrovision on the inputs by selecting record/pause while feeding in a "clean" signal, then quickly switching to the Macrovision-protected signal -- if it did not time out and go into "no signal", then it would not flash the dreaded COPY PrOt. However, there's no reason why it should pass a Macrovision-free signal out as E-E, if it was removing it digitally during recording; so you would have to record your film onto a DVD+/-RW disc (or the HDD if available) and watch it later. (Possibly just a few seconds later, if the recorder supported "chase mode", a.k.a. playback during recording.)

The easiest way (and probably how the no-longer-available "video enhancers" used to do it) would be to use a 1881 sync separator; a microcontroller; and a 4053 changeover analogue switch IC to switch between a fixed black level with superimposed syncs or the raw video, depending on the current video line. (You probably could manage without the micro; but you would need a lot of 4000-series CMOS logic ICs, and it would be much harder to make it work with 625/25 or 525/30 signals. A micro could easily count the H sync pulses between successive V sync pulses and determine automatically the number of lines in the picture, and so when to switch.) For the top of the picture, before the beam reaches the visible screen, you switch out the corrupt video signal and supply instead a constant black level (from a multi-turn pot), onto which you superimpose a regenerated H and V sync signal. For the visible lines, you switch back to the raw video signal. Then for the last few lines below the visible picture and the vertical blanking time, you switch back to the artificial black again. This prevents the automatic gain control circuitry from incorrectly setting itself against the noise level, rather than the wanted picture signal level.

Incidentally, I had always thought that the noise in the vertical blanking interval was just an artefact of the mass-production process that they didn't bother doing anything about. It was only later that I found out it was deliberate! Obviously the foregoing is only intended to be used for legitimate purposes, such as making recordings that you legally own, playable on modern equipment with which they would otherwise be incompatible, within the scope of any applicable licence. TL;DR Don't blame me if you get caught doing anything you shouldn't.

[Argus25]

Originally Posted by julie_m

The easiest way (and probably how the no-longer-available "video enhancers" used to do it) would be to use a 1881 sync separator; a microcontroller; and a 4053 changeover analogue switch IC to switch between a fixed black level with superimposed syncs or the raw video, depending on the current video line.

This was the common one in Australasia:

http://archive.siliconchip.com.au/cm...2/article.html

It has the LM1881, but it doesn't have a PIC micro, just common logic IC's, so its very easy to make & get parts for. It is the one I used for some years for VHS dubs etc. There are probably some still around, but you can easily get the circuit for it from SC. Jaycar sold the unit in kit form.

[mark2collection]

There are a number of workarounds.

If you have the devices with these connections, feed the DVD player into an S-VHS VCR via the Chroma-Luma round socket, or use a Fisher (Sanyo) VCR which never seemed to worry about Macrovision, or Google 'Macrovision remover', the circuit on hbo.tripod was a circuit I read about & made back in 2004 after having no access to an S-VHS machine/Fisher VCR, but having a TV with no scart socket.

The RF modulator I robbed from a scrap CCTV camera matrix unit, but still had to make the circuit as I was seeing oddities on-screen. The circuit allowed me to watch later releases of films from DVD on my old Telly

These days, in the main house we have new TV's, my escape room however, has the CRT sets from the house connected via RF to a current DVD player between which connects an HDMI to a scart converter, piped through my VHS machine.

Best of both worlds, I can now enjoy my VHS tapes or latest blu-Ray DVD's on my old TV. At one stage I had a Rasberry Pi connected too, but reading the text was difficult!

As others have said, there's also the option of an RF modulator on its own. Look out for a scrap 3V29 or similar generation VCR, the RF modules in these typically need 12 Volts, ground, video & audio in, couple the signals via 10uF's, happy days.

Mark

[hamid_1]

In your case, I think using a standalone modulator instead of a VHS machine should solve the problem, but if you want to eliminate Macrovision altogether, there are a number of ways.

A small number of DVD players, mainly the early ones, had a secret menu, from which you could turn off Macrovision. You just needed to press a few buttons on the remote control. DVD players with the hidden menu included Dansai DVD852 and DVD-1010, Afreey LD-2060 and various others. On some DVD players, there was no menu option to turn off Macrovision but you could load different firmware on them to turn it off, e.g. Apex AD-500W, Wharfedale M5 DVD player, Liteon LVW-5045 DVD recorder.

If you're not lucky enough to have a hackable DVD player, there's another way. On commercial, Macrovision protected DVD movies, a flag is set which tells the DVD player to add the Macrovision signal when playing. Home recorded DVDs and some special-interest discs like music and documentaries don't have the Macrovision flag. This is because the DVD producers have to pay a royalty fee to Macrovision Corporation in order to be allowed to add it to their disc. For some smaller productions, it's considered not worth the cost. Consequently those discs are Macrovision free.

If your disc is Macrovision protected, you can 'rip' it to your PC using a bit of freely available software called DVD Decrypter. In the process, you have the option to remove the Macrovision flag and any region codes. You can then 'burn' a backup copy using your PC DVD writer; this copy will be Macrovision free.

There were some commercial producers of Macrovision removal devices, notably the Sonel MacroMaster (looks like a SCART lead and is used in the same way, but contains a small circuit board inside). The sonel.co.uk website closed down a number of years ago, I suspect due to legal action by Macrovision Corporation. Rather cunningly, Macrovision patented just about every method they could think of to defeat their protection, then sued anybody who made devices. You might still find one secondhand; the Sonel SCART lead was quite popular in its day, as it also allowed recording of pay-per-view Sky movies and other copy-protected material. However, Sonel claimed their devices were not for piracy; they were offered as a solution for owners of TV sets with built-in VHS recorders who were suffering the effects of Macrovision while watching legitimate sources.

[1100 man]

Thank you all for the detailed responses! I assume Macrovision works by inserting variable amplitude pulses in the frame blanking period. These are then seen by the AGC in the video recorder which then keeps altering the gain. Surely these pulses will stay on the video signal once it passes through a modulator, so they will still be there once the signal is demodulated in the TV. Thus the TV's AGC will still be affected by them?

Nick

[ben]

A handful of sets were affected but most not. The macrovision pulses are in the vertical blanking interval, so there's nothing for the screen to show at that point.

Think about it, if all TVs were affected, then the big corporations wouldn't sell many prerecorded tapes!

[Richard_FM]

Maplin used to sell the YU-13 Video Stabilizer/Enhancer which would get around Macrovision, but not advertised as such!

http://www.dustygizmos.com/arcpages/...Maplin%20YU-13

I've not checked but I'm sure some turn up on eBay every now & again.

[Ambientnoise]

There was a similar recent thread. Velleman used to do a “video processor” kit, you might still find one somewhere.

Ken

[dvcam11]

If your source material is on DVD the use DVD_Shrink which will get rid of nearly all copy protection.

https://en.wikipedia.org/wiki/DVD_Shrink

[irob2345]

I designed a modulator that incorporates a Macrovision stripper (it actually cleans out the entire vertical blanking interval so it works for timecode as well) along the lines described.
It works very well. It's particularly useful for 50s TVs that often have very rudimentary blanking arrangements. Unlike other designs I've seen it retains black level.

http://www.siliconchip.com.au/Issue/...intage+TV+sets

Silicon Chip magazine also has the PCB.

The modulator is VHF only but the design has a video output so for UHF-only UK you could just build the processor part.

Generally, TVs designed prior to about 1974 will need this. As well as a few later models!

Here (hopefully) is a schematic.