ABSTRACT
Arithmetic Coding As in the preceding chapter, we have a source alphabet S = {s1, . . . ,sm} and relative source frequencies f1, . . . , fm , presumably estimated by a statistical study of the source text. However, in arithmetic coding it is not the case that individual source letters, or even blocks of source letters, are replaced by binary code words (although replacing blocks of source letters by binary words derived arithmetically is an option; see Section 6.3). Rather, the entire source text, si1 · · · siN , is assigned a codeword arrived at by a rather complicated process, to be described below.
