Title :
Better than “optimum” homophonic substitution
Author :
Da Rocha, Valdemar C., Jr. ; Massey, James L.
Author_Institution :
UFPE, Recife, Brazil
Abstract :
A perfect homophonic coding technique is devised for which the number of fair coin tosses to select a homophone is bounded for any source with rational letter probabilities. The new scheme enlarges the source alphabet, which paradoxically generally results in less plaintext expansion than does “optimum” homophonic coding of the unaugmented source
Keywords :
cryptography; source coding; fair coin tosses; homophone selection; optimum homophonic substitution; perfect homophonic coding technique; plaintext expansion; rational letter probabilities; source alphabet; unaugmented source; Brazil Council; Costs; Decoding; Encoding; Entropy; Probability distribution; Random variables; Testing;
Conference_Titel :
Information Theory, 2000. Proceedings. IEEE International Symposium on
Conference_Location :
Sorrento
Print_ISBN :
0-7803-5857-0
DOI :
10.1109/ISIT.2000.866539
