Method for coding adapted to the recognition of synchronisation words in a sequence of words coded with a variable-length code

摘要

PCT No. PCT/FR89/00521 Sec. 371 Date Jun. 18, 1990 Sec. 102(e) Date Jun. 18, 1990 PCT Filed Oct. 10, 1989 PCT Pub. No. WO90/04885 PCT Pub. Date May 3, 1990.The encoding method is adapted to the recognition of synchronization words in sequence of variable length encoded words, each encoded word corresponding to a specific message or event from a sequences of messages each assigned with a probability of occurrence. The method consists in constructing a dichotomizing encoding tree comprising a specific number of leaves (F1 . . . F4) distributed over priority levels (n1 . . . n4) classified in a decreasing order on processing from the root of the tree towards the leaves, the number of leaves being equal to the number of events to be encoded, in placing the leaves adjacent to one another on each level, the leaves corresponding to the most probable events being placed at one end to the right or to the left on each level, and in prohibiting, in the encoded words, the sequences of Smax bits of equal value, zero or one, in order to obtain an easy choice of synchronization words.