X-Message-Number: 18824
From: "John de Rivaz" <>
References: <>
Subject: Re: Longevity of compressed digital data
Date: Sat, 16 Mar 2002 10:56:36 -0000

I have posted some early articles from the inventor of PCM which include
predictions made in the mid to late sixties about the life we lead now. The
predictions are obviously telecommunications based. In some cases it seems
like a weird parallel universe, although the basic principles were correct.
Find them here http://www.AlecHarleyReeves.com At the time of writing these
articles, the concept of personally owned computers of the power of the
average PC sold today for 1/20th the price of a car would have been
inconceivable. Therefore the concept of the Internet and video compression
by computer (rather than clever analogue circuits) is not to the forefront
of these articles, and arguably not even present.

The best shot at video compression as I can recall from these times was to
have a system whereby each dot on the vacuum tube image scanner was sent to
a separate "thin film" circuit that sent its brightness as a single channel.
If all the millions of channels had a very narrow bandwidth, motion would be
blurred but the overall bandwidth of the video picture would be as low as
you like. The lower it is the  more blurred motion becomes.

Such an idea was then and is now totality impracticable, but it does show
theoretically that a low bandwidth video signal can be sent. The actual
result of modern video compression produced exactly the same result - still
picture OK, motion blurred. The method (computation at very high speed) was
equally impracticable in the 1960s.

One wonders whether all the things that so called experts in medicine say
are impracticable about cryonics will eventually find solutions that are way
outside what people are speculating about today.

--
Sincerely, John de Rivaz:      http://www.deRivaz.com :
http://www.AlecHarleyReeves.com
http://www.longevity-report.com : http://www.autopsychoice.com :
http://www.cryonics-europe.org
http://www.porthtowan.com

>>>
 Message #18822
 From: "Solion" <>
 Subject: RE: Your last cryonics wishes on CD/Video Tape
 Date: Fri, 15 Mar 2002 20:10:15 -0800

 ER, Don't belive that for a second. I have several pieces of video I could
send you
 that were encoded in a format from the Windows 3.11 days that will not play
on my
 Windows XP machine.  the only way to ensure playback is to "shotgun" as
many
 formats you can and hope one plays.

 (((((If you look at the state of mp3 technology today, you can play mpeg
files
 from 3-5 years ago easily, the quality will not be good, but it does it))))

 Ahhh, 3- 5 years really is no test of time. Lets see if your MP3s play in
10 - 15. years
 with the updates of digital codecs comming fast and furious, Don't count on
it. .
<<<

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