Patent ID: 6049633
Filing Date: 2000-04-11
Classification: H03M

Abstract:
A method for arithmetically encoding input data, wherein the input data is a sequence of K types of symbols, with K being an integer greater than 1, comprising the steps of:(a) initializing contents of a codeword table with K codewords, wherein each codeword corresponds to one of the K types of symbols and a count value for said each codeword is set to 1;(b) extracting 1st to Mth symbols from the input data, M being a predetermined positive integer representing a maximum length of codewords to be registered at the codeword table;(c) assigning a probability value to each codeword based on the count values, wherein the sum of the assigned probability values is 1;(d) generating M codewords based on the extracted M symbols;(e) classifying a generated codeword into a registered group if the generated codeword is already registered at the codeword table; and classifying a generated codeword into an unregistered group if otherwise; and(f) allocating a probability value of a longest codeword to a group of symbols consisting of first L symbols of the extracted M symbols and increasing the count value for the longest codeword by 1, wherein the longest codeword is a longest codeword among the codewords in the registered group and consists of L symbols, with L being an integer greater than 1.