albert@ucbvax.ARPA (Anthony Albert) (04/27/85)
Does anyone know how this latest scheme is supposed to work? It seems to me if the TV can play a signal, a VCR should be able to record it, and vice-versa. If a VCR can't record it, won't people have trouble watching it on TVs? -- Anthony Albert ..!ucbvax!albert albert@ucbvax.ARPA
man@bocar.UUCP (M Nevar) (04/27/85)
I read someting about how the new anti-piracy thing in the USA Today. It has something to do with using an additional signal that will get recorded along with the movie and scramble it up. Anyone else ?
wapd@houxj.UUCP (Bill Dietrich) (05/03/85)
Here are some excerpts from an article in the Asbury Park (NJ) Press, Tues April 30, 1985. "New Techniques Thwart Illegal Video Tape Dubbers", by Jonathan Takiff, Knight-Ridder Newspapers. Page C8. ... Their illegally made dub will be virtually unviewable - marred by over-saturated colors, excess graininess and wiggly lines across the screen. ... "The Cotton Club" is the first home video release to employ a new anti-copying protection system developed by Macrovision of San Jose, Calif. ... Inventor John Ryan (formerly chief engineer of camera development for Ampex) ... ... Unlike previous "copyguard" anti-piracy technologies applied to tapes, Macrovision's copy-jinxing system does not effect [sic] the normal viewing of a protected tape when it is fed directly from a VCR to a TV set. "Copyguard inadvertently caused the picture (from an authorized tape) to roll on some televisions, as well as spoiling tape copies. So there was a legitimate reason for people to make, sell and buy "stabilizers" that corrected the (vertical synchronization) problem," notes Ryan. "Our system delivers 100 percent viewability by attacking a weakness in the automatic gain control circuitry that's particular just to VCR's." ... [techniques are different for Beta and VHS because AGC circuitry is different] ... [technique can also be applied to laser and CED-format videodiscs] ... Bill Dietrich houxj!wapd