RedHuffman | SuperCollider 3.13.0 Help

Description

The principle is "to use fewer bits for more frequently occurring character".

See http://www.cs.duke.edu/csed/poop/huff/info/

NOTE: Works with Integer, Float and Symbol. Can also take a String instead of an Array.

Class Methods

.compress

Compresses an array into a string of binary numbers. Creates a *tree and a *dict as well.

.decompress

Decompresses a binary string into an array. Make sure you use the right *tree and *dict as generated by the compress method.

.binaryStringToBytes

Converts a binary string into 8-bit bytes. Up to 7 zeros might be padded automatically at the end. The number of zeros is stored in *pad. *pad is semi-private and used when converting back to bytes.

.bytesToBinaryString

Converts an array of 8-bit bytes into a binary string.

.pad

Semi-private counter for number of padded zeros. Set by *binaryStringToBytes and read by *bytesToBinaryString.

.dict

Look-up dictionary with values and binary strings.

Examples

a= "000001111233333333".ascii;
b= RedHuffman.compress(a);
RedHuffman.binaryStringToBytes(b).size/a.size;  //compressed to 28%
c= RedHuffman.decompress(b);
a==c;

a= "streets are stone stars are not".ascii;
b= RedHuffman.compress(a);
RedHuffman.binaryStringToBytes(b).size/a.size;  //compressed to 39%
c= RedHuffman.decompress(b);
a==c

a= "go go gophers".ascii;
b= RedHuffman.compress(a);
RedHuffman.tree;  //current tree
RedHuffman.dict;  //current dict
c= RedHuffman.decompress(b);
a==c

a= "go go gophers";  //or with a string argument
b= RedHuffman.compress(a);
RedHuffman.tree;  //current tree
RedHuffman.dict;  //current dict
c= RedHuffman.decompress(b);
a==c.join

a= [0, 0, 0, 0, 1.5, 1.5, 1.5, \abc, \abc, \testing];
b= RedHuffman.compress(a);
RedHuffman.tree;  //current tree
RedHuffman.dict;  //current dict
c= RedHuffman.binaryStringToBytes(b);  //this is the data you can save in a file
c.size/a.size;  //30% smaller than the original
d= RedHuffman.bytesToBinaryString(c);
e= RedHuffman.decompress(d);  //here is the data expanded again
a==e

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= RedHuffman.compress(a);
c= RedHuffman.binaryStringToBytes(b);
c.size/a.size;  //53% smaller than the original
d= RedHuffman.bytesToBinaryString(c);
e= RedHuffman.decompress(d);
e==a

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

RedHuffmanExtension