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Replacing a Dictionary with a Square Root

By Tom Cargill, October 01, 2001

Data that compresses well under a run-length encoding mechanism can be encoded in a way that is compatible with LZW's output, but independent of its patented algorithm.
Oct01: Algorithm Alley 

 1: a
 2: aa
 3: a(0)
 4: a(0)a
 5: a(0)(0)
 6: a(0)(1)
 7: a(0)(1)a
 8: a(0)(1)(0)
 9: a(0)(1)(1)
10: a(0)(1)(2)
11: a(0)(1)(2)a
12: a(0)(1)(2)(0)
13: a(0)(1)(2)(1)
14: a(0)(1)(2)(2)
15: a(0)(1)(2)(3)
16: a(0)(1)(2)(3)a
17: a(0)(1)(2)(3)(0)
18: a(0)(1)(2)(3)(1)
19: a(0)(1)(2)(3)(2)
20: a(0)(1)(2)(3)(3)

Figure 1: Output of generateCompressMapping in Listing Two.



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