Variable Length Prefix Encoding

摘要

The problem of constructing minimum-redundancy prefix codes for the general discrete noiseless channel without constraints is considered for unequal code letter costs. Two cases are considered; the symbols encoded are assumed to be equally probable, and the symbols encoded are not restricted to be equally probable. A graphical technique is developed for solving the problem for which the code words are equally probable and are constructed from r symbols where r > or = 2. The solution technique is valid either in the presence or absence of the exhaustive constraint. A selective enumeration technique is developed for solving the problem in which the code words are not equally probable and are constructed from r=2 symbols. The computational feasibility of the solution technique is demonstrated. (Author)