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Re: Compression of random binary data

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On 7/11/2016 5:20 PM, nuny@bid.nes wrote:
> On Monday, July 11, 2016 at 10:50:49 AM UTC-7, jonas.t...@gmail.com
> wrote:
>> What kind of statistic law or mathematical conjecture  or is it
>> even a physical law is violated by compression of random binary
>> data?

> When you say "random binary data" do you mean a binary data set that
> carries no information, or any information-carrying binary data set
> one might choose at random?
>
> If the latter it depends on how you compress it but you will almost
> certainly lose *some* data. In other words you will not be able to
> recover the original data set in its entirety.
>
> Sergio mentioned lossless compression schemes that discard sequential
> strings of ones and zeros (but remembers how many and where they
> went).

I think a version of that was used by Ma Bell, I think they would count 
up a certian  number of 0s (or 1's) then put in a control character (in 
binary) followed by a count#, then repeat as required, it may have been 
for a system that had "dead time" charastics, and it did compress the 
data, by eliminating portion of the dead time, which is unlike true 
random characteristics.

also it seems to comply with Shannon's "The average length of an encoded 
symbol is greater than or equal to the Entropy."  'average' is the key word.



> Notice that if you do that to random data the result may not
> be as random as the original. Hence in that case it is "lossy" in
> that it loses some randomness.
>
>
> Mark L. Fergerson
>

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Compression of random binary data jonas.thornvall@gmail.com - 2016-07-11 10:50 -0700
  Re: Compression of random binary data xxein1@att.net - 2016-07-11 13:12 -0700
  Re: Compression of random binary data Sergio <invalid@invalid.com> - 2016-07-11 15:42 -0500
  Re: Compression of random binary data Double-A <double-a3@hush.com> - 2016-07-11 13:58 -0700
    Re: Compression of random binary data Poutnik <poutnik4nntp@gmail.com> - 2016-07-11 23:12 +0200
  Re: Compression of random binary data "nuny@bid.nes" <Alien8752@gmail.com> - 2016-07-11 15:20 -0700
    Re: Compression of random binary data Sergio <invalid@invalid.com> - 2016-07-11 21:29 -0500
  Re: Compression of random binary data Lofty Goat <rlwatkins@gmail.com> - 2016-07-11 17:48 -0500
  Re: Compression of random binary data Fabian Russell <fb@zen.info> - 2016-07-11 23:39 +0000
    Re: One _never_ knows if data is truly random or not. Fabian Russell <fb@zen.info> - 2016-07-12 14:33 +0000
      Re: One _never_ knows if data is truly random or not. Poutnik <poutnik4nntp@gmail.com> - 2016-07-12 18:37 +0200
    Re: One _never_ knows if data is truly random or not. benj <benj@nobody.net> - 2016-07-12 19:26 -0400
  Re: Compression of random binary data Sylvia Else <sylvia@not.at.this.address> - 2016-07-12 15:20 +1000
    Re: Compression of random binary data Double-A <double-a3@hush.com> - 2016-07-12 13:29 -0700
      Re: Compression of random binary data Sylvia Else <sylvia@not.at.this.address> - 2016-07-13 16:29 +1000
  Re: Compression of random binary data Michael J. Strickland <michael06582@comcast.net> - 2016-07-14 00:54 -0400

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