[kwlug-disc] are you going to be a criminal?

Bob Jonkman bjonkman at sobac.com
Sun Jun 6 23:31:05 EDT 2010

Analoge video copy protection reduces the strength of the horizontal 
sync signal in the video.  After copying the h.sync is near absent, so 
that the picture drifts into unrecognizable waviness.  The audio is 
unaffected, tho.

However, anyone with professional quality editing equipment will have a 
sync generator, which can handily replace the faded h.sync signal from 
the original, allowing reasonably high quality copies.  Of course, 
equipment of this calibre is horrendously expensive, making analogue 
copy protection effective for most of the consumer hordes.

With digital copy protection the circumvention is achieved through 
software encoding (not encryption since there is no separable key 
material, or the keys are distributed with the material).  Decoding is 
achieved with more software, and software, as we in the FLOSS community 
know, is often Free-As-In-Beer.

There is no longer an expensive barrier to consumers, and so legal 
barriers must be erected instead.


On Sat, 05 Jun 2010 at 23:01, unsolicited <unsolicited at swiz.ca> wrote 
about Re: [kwlug-disc] are you going to be a criminal?:
> With a protected tape (Macrovision?), you cannot go to another (VHS?) 
> recording device. Even, e.g., you play out from the VCR to the TV, and 
> out from the TV to another VCR, the TV is passing through the 
> protection (I forget whether it's a signal, a flag, a what, but - 
> remember, this is an analogue medium, still, at this point.)

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