Copy-protection for vinyl in the 1970s (2008)
currybet.net
currybet.net
There was also apparently another method which was just a straight up lie, called KTC, that claimed it was coated with a chemical that would destroy any VHS recorder attempting to record it. Here's a screenshot of the pre-video bumper warning, alerting you to "STOP RECORDING NOW" [2]. Also any RedLetterMedia fans may remember this from the "dog sitting" video in Wheel of the Worst #7 (around 35:00 in). It sounds like a phony technology, and it is. It's just a lie intended to scare away anyone attempting to record the tape.
[0] https://www.youtube.com/watch?v=-VqsU1VK3mU
[1] https://en.wikipedia.org/wiki/Analog_Protection_System
[2] https://company-bumpers.fandom.com/wiki/K.T.C._Warning_Scree...
They will enable things like Amazon or Roku HDMI dongles to work with computer monitors that do not support HDMI encryption. The most common use is just that, not to pirate anything.
But now if I wanted to pirate something I could. It would be super easy too, since there's an open port I could plug the recorder right into.
Betamax was limited to tape speed and how much tape could fit in the cassette. It was one of the downfalls of Beta. It only recorded at one speed. VHS could record in 3 speeds SP (normal), EP (half speed doubling record time), or SLP (third speed tripling record time). At the end of VHS, they were able to create an extremely thin tape allowing for 180 minutes of SP time in the cassette. In SLP, that's 9 friggin hours of record time. It looked horrible, but people loved it. People were essentially running their own DVR with a programmable VCR in SLP with a 180 minute load. You had to fast forward/rewind to find your shows, but even commercials we being skipped.
An answer here https://photo.stackexchange.com/a/21181 says it's to do with codec licensing but the businesswire link is dead and I can't find anything else to back it up.
In the beginning, yes. As time went on, Beta also offered three speeds (Beta I, II, and III) exactly as was offered by VHS and their three speeds.
Maximum recording time for Beta ended up at 5 hours on a single cassette (L830 cassette and Beta III speed). The L750 cassette was more commonly available, it recorded 4.5 hours at Beta III speed.
Of course, VHS's physically larger cassette always allowed it to have a somewhere longer recording time at every step of the competition.
Edit: Add link to Wikipedia page for Beta tape lengths and recording times:
As time went on, longer cassettes and slower recording speeds were released and Beta recorders eventually had tape cassettes available that recorded for 4.5 hours (L750) or 5 hours (L830) of time on a single cassette.
On a related note, one of the copy protection systems I put on some Sinclair Spectrum cassette games involved changing the baud rate part way through loading.
It was over 35 years ago so the details are hazy, but I had a custom "master maker" to play the audio[1] and at a specific byte count would change the frequency. The mastering and duplication machines coped with it fine and the loader was written to expect it, but it threw out most home tape to tape systems for reasons I can't exactly remember.
[1] These were usually recorded directly from the Spectrum onto 2 inch reel to reel tapes in a studio, that was then used as the master at the duplicators.
- Nagravision on a Pentium 2 was trivial to decode
- Soccer
- Porn
- Blockbusters
The whole DRM design pattern is a chain of weak links designed to keep a product from working. The customer is only satisfied if and only if nothing in the chain broke today, yet.
So some people have obtained the correct record stylus for these, made a 2 inch hole filler, set a modern turntable to the correct speed, and transcribed these records. If you like 1950s elevator music, it's available.
There was a rumor that Sony bought CBS Records (now Sony Records) just to shut that nonsense down.
But especially then, most students had little experience with computers and just believed it.
Is vinyl really that delicate, or were record players in the 60's put more downforce on the needle?
Either way, in this case the article is referring to the ultrasonic tone, and not to the records overall.
All mechanical record players have to pick a middle ground between picking up the sound wave and keeping the record surface pristine.
To prevent wear, you want the needle to exert as little pressure as possible. That calls for a large needle that’s only lightly pressed onto the record surface.
Unfortunately, that is exactly what you don’t need if you want to reliably pick up the signal.
To prevent the needle from jumping from peak to peak in the groove due to its inertia, you want to press it onto the disk.
Also, for the needle to pick up higher frequencies, it can’t be large (it has to be able to ‘fall’ into the grooves between the tops in the signal, and those are closer together for higher-frequency signals)
False. There's an EQ curve that's applied to all records that rolls off the bass, which has to be re-added by the preamp.
Edit: I remembered that my dad frequently added a small coin on the top of the needle to avoid skips. So people weren't gentle with the vinyls and the needles either.
It could also be that vinyl and RIAA encoding was made mostly for the range of the human ears, and such a high frequency would just wear way faster than the "normal" ones, but I'm speculating there. IIRC, the high frequencies are "higher" in the groove.
But repeated pressure does deform it slightly. And the HF detail in the groove is already so tiny that it doesn't take much to wear/deform it away.
Vinyl really is the most ridiculous medium for music. I get the appeal of a large collectible object wrapped in stunning sleeve art, but in terms of audio quality it's the equivalent of a cheap plastic LOMO lens.
https://patentimages.storage.googleapis.com/3d/d5/b4/5beda28...
> An anti-copy system which prevents copying of tapes and records and other source material by placing a degrade signal on an analog source signal to be recorded on a recording device. One embodiment of the system includes a pulse width modulation (PWM) circuit that generates a pulsed signal in a frequency range from near the upper end to well above the range of hearing.
> However, attempts to make taped copies of the original recordings cause the degrade signal to beat against the bias oscillator frequency of the tape recording head, thereby creating harmonic signals that result in distortion and noticeable alteration of the reproduced source signal that are unpleasant and objectionable to the listener.
The compiler could move the outer loops to the external CPU, and leave the inner loops to the main CPU which is faster. Of course you would have to think about how you move data around, but in principle why wouldn't this work?
In the entire history of software there was absolutely zero copy protection for a determined person. Not just commercial one, but think of FBI/NSA/CIA level of protection, and yet they failed spectacularly when a determined individual wanted to steal the secrets. Hence my above "if it can be read, it can be copied".
The battles between the companies and hackers in that scene were fascinating.
I guess these days you could have a USB-device that did useful calculations, so without it software would give the wrong/broken results. But I've not come across anything like that in recent times.
But to answer why this wouldn't work, I'm not particularly involved in cracking / reverse engineering, so maybe someone will chime in with better answers, but. If your code requires portions of it to run on my main CPU, can't I just black-box reverse engineer your external CPU?
And like you say, ARM CPUs are very cheap, so with an iFixit kit and some soldering skills, couldn't I just move your ROM over to a raspberry pi or etc?
Lastly, as a customer this heavily limits how I can use your software. So unless there are absolutely zero alternatives, I would just avoid purchasing this at all.
It reminds me of what iLok has been trying / tried to do in the music production space. Originally it was a DRM scheme that required a USB dongle to run any iLok protected audio plugins. It wasn't too long until iLok server cracks existed. And while I don't have any insights into iLok or companies that chose their dongle based protection, almost every single plugin maker that used the iLok dongle has now moved away from it and iLok now offer a dongle-less DRM scheme comparable to other activate-via-internet methods.
Edit: Another popular example in music production is Universal Audio plugins. These don't just offload parts of the application to a similar processor for DRM purposes, but actually have dedicated SHARC DSP processors which they offload the processing onto. These plugins have stuck around without angering the general community because it's not purely a copy-protection method. They actually remove significant amounts of processing from your main CPU onto their DSP processors. This has become less significant as CPUs have gotten better and better and requires a minimum $900 hardware investment up front. But it is still a more legitimate reason for a "dongle" than being just DRM.
Not really if the hardware costs $5 and the software $1000, wouldn't you agree? Also, the same hardware-design can be used for different software products.
> couldn't I just move your ROM over to a raspberry pi or etc?
Well, you could tamper-proof it. For example, wrap a thin copper wire around the board, and immerse the entire thing in epoxy. When someone tries to get to the CPU or flash memory, the copper wire breaks and the flash is reset. Or something like that.
I don't really agree. Like in my example of the iLok. The iLok was usually free with any compatible plugin purchase and was certainly cheap to produce. Customers still viewed it as a hardware product. Working at a different studio that day and you forgot your iLok? Tell your customer you can't work with them until you drive back home. Lost your iLok somewhere? You can't work until they next-day ship you a new key. It is not a software product.
> Well, you could tamper-proof it.
I'd say tamper-resistant, you can never really make it tamper-proof. Some youtubers will really surprise you with what they can break into. It also raises production costs more, as you're not buying an off-the-shelf device, and creates more potential customer issues. Is there any chance that if I drop the device, it triggers your tamper-resistant scheme? Etc etc.
It's always a game of cat and mouse with these things. The only way to make something completely un-copyable is to never release it. (even server-only applications can get bootlegged with enough dedication. Look at private MMO servers). Otherwise you're just making it more difficult to do, and have to decide if the tradeoff of deterring piracy is worth the additional costs to research/develop/produce and the potential anger it can cause actual paying customers. Every industry probably has it's own sweet-spot, I don't think it's something that has a one-size-fits-all answer. As much as I would love to say just abandon DRM/copy-protection altogether, there are probably situations where it is a net-positive for the producer.
Just a funny anecdote, but my main project is a SaaS application. We were in a meeting with one company who was demoing something for us, and we caught that they were using my app as one of their dependencies! One of our customers was reselling it to them, through a proxy, obviously against contract. Our company was still really small at the time, it got brought up with the CEO. He decided to just let it slide and to add something to the API response saying that the API was ours and what our website was.
https://cpl.thalesgroup.com/resources/software-monetization/...
But this is less about copy protection than about the need to keep rogue (i.e., bot/malware) from being installed on the box.
I can't tell you the number of times that titles have been released with howlers like "check online friend status every 60th of a second" (via a REST request). Use of Denuvo would likely follow that . . . pattern.
When they make a promise to the developers that "this game won't be cracked for X days/weeks" what they are saying is they are putting in so much extra code that it will take the crackers that much time to reverse engineer it. It's basically "we are adding this much busywork to your game". When some AAA publisher opts for the longest possible length it turns into a performance impacting amount of busywork.
I wish more game companies would then ship the un-denuvoed version once the main version was cracked and released on pirate sites. Just do it quietly in a patch with a bullet point of " * slightly improved performance".
I've never seen a contract for Denuvo, but I've seen enough similar ones to extrapolate a bit. I suspect that it contains some provision to guarantee a certain number of days before a crack is released. If that's the case, it would make sense that they would stipulate/strongly recommend that checks be littered throughout the codebase, triggered by pre-defined operations. And I could see developers putting some of these operations in the core gameplay loop, not foreseeing the requirement to run a DRM check each time it is triggered.
Plus, it's usually patched out after a certain number of days, so there's probably not too much incentive to worry too much about performance.
Not apologizing for crappy behavior, but I can understand how it happens.
Sometimes it's not very benign, there has been more than one example of a game with noticeably improved performance once cracked to remove it.
Picture this: you have a 50-100K+ of scientific equipment. It plugs into a computer via usb (if you are lucky), parallel, serial, or something proprietary (if you are unlucky). Now you need a special piece of software to run said hardware. Of course that software has to have a physical hardware liscense key, because the expensive hardware isn't enough, it too can be usb (you hope) but parallel can be found. You also have a software license on served by the lowest budget server in a foreign country, that randomly pings to make sure you aren't using it on more than one computer. This can happen a few times an hour to a few times a month, and the software is completely unusable until that ping completes.
To complicate things, some companies do all of this, and also provide the computer that the equipment comes with. All the software is locked down to that computer, and any changes to the computer hardware (ram upgrades, new hard drive) cause the software to not boot at all.
And that kids is how some companies lock you into long term service agreements.
At least you own the hardware.
And so unnecessary since the expensive piece of test equipment is already a huge dongle. All of that DRM nonsense is making your life worse for no gain whatsoever. It's not good when people who bought the software legally (often for 6 figures) are looking into how to pirate it because they're losing valuable time on expensive equipment to your copy protection nonsense.
Really??? Play it backwards :)
> "Magic Alex" Mardas was not the revolutionary engineer he portrayed himself to be. In 1995, in an article about what became of The Beatle's hangers-on, The Independent described him as:
> 'The Greek TV repairman, set up in Apple Electronics by the Beatles, who promised to build an artificial sun, a telephone you told who to call, wallpaper loudspeakers, a house which hovered supported by an invisible beam, and even a flying saucer. Not one invention was made, and the recording studio he built proved unusable and was demolished. Allen Klein fired him, and he has since disappeared.'