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. . <<< Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=18824