RedLZW | SuperCollider 3.13.0 Help

Description

See http://en.wikipedia.org/wiki/LZW and http://marknelson.us/1989/10/01/lzw-data-compression/

A dictionary look-up compressor that performs well with both highly repetitive data and repeating patterns e.g. [0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 3, 3, 3, 3, 3, 3, 3, 3, 0, 1, 2, 3, 0, 1, 2, 3, 0, 1, 2, 3].

NOTE: Only works with 8bit Integer (0-255) values.

Class Methods

.compress

Expects an array of 8bit integers. Returns an array of integers.

.decompress

Array of integers. Returns an array of 8bit integers.

Examples

a= [0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 3, 3, 3, 3, 3, 3, 3, 3, 0, 1, 2, 3, 0, 1, 2, 3, 0, 1, 2, 3];
b= RedLZW.compress(a);
b.size/a.size;  //compressed to 60%
c= RedLZW.decompress(b);
a==c

a= "TOBEORNOTTOBEORTOBEORNOT".ascii;
b= RedLZW.compress(a);
b.size/a.size;  //compressed to 66%
c= RedLZW.decompress(b);
a==c;

a= "/WED/WE/WEE/WEB/WET".ascii;
b= RedLZW.compress(a);
b.size/a.size;  //compressed to 63%
c= RedLZW.decompress(b);
a==c;

a= "JOEYNJOEYNJOEYJOEYNJOEYNJOEYJOEYNJOEYNJOEYJOEYNJOEYNJOEY".ascii;
b= RedLZW.compress(a);
b.size/a.size;  //compressed to 37.5%
c= RedLZW.decompress(b);
a==c;

a= "Man is distinguished, not only by his reason, but by this singular passion from other animals, which is a lust of the mind, that by a perseverance of delight in the continued and indefatigable generation of knowledge, exceeds the short vehemence of any carnal pleasure.".ascii;
b= RedLZW.compress(a);
b.size/a.size;  //compressed to 69%
c= RedLZW.decompress(b);
a==c;

a= "this_is_his_thing".ascii;
b= RedLZW.compress(a);
b.size/a.size;  //compressed to 76%
c= RedLZW.decompress(b);
a==c;

a= "abcabcabcabcabcabc".ascii;
b= RedLZW.compress(a);
b.size/a.size;  //compressed to 50%
c= RedLZW.decompress(b);
a==c;

helpfile source: HelpSource/Classes/RedLZW.schelp
link::redSys/Classes/RedLZW::

RedLZWExtension

Description

Class Methods

.compress

.decompress

Examples

RedLZW
Extension