Coded data generation or conversion – Digital code to digital code converters – Adaptive coding
Patent
1995-03-20
1997-09-02
Young, Brian K.
Coded data generation or conversion
Digital code to digital code converters
Adaptive coding
341 67, 341 95, 341106, 341107, H03M 742
Patent
active
056637217
ABSTRACT:
A data compression algorithm in which a word is assigned a code value according to the frequency of the word occurring, for example, in the English language. The code value contains a length field and a code field. The number of bits used to represent the length field is fixed, whereas the length of the code field is variable. The code field can be assigned values between 0b0 and 0b11111111111111. The value 0b0 is assigned for the word having the greatest probability of occurring and the value 0b11111111111111 is assigned for the word having the least probability of occurring. The value of the length field is equal to the number of bits contained in the code field. The code values are stored in a dictionary with their corresponding words. If it is determined that an input word does not exist in the dictionary, then the length field is assigned the value 0b0000 and the word is represented in its ASCII code. Examples of dictionaries that can be used with the compression algorithm are the English dictionary, Spanish dictionary, German dictionary, a dictionary for engineering applications, a dictionary for lawyers, and a dictionary for bioscientists.
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Compaq Computer Corporation
Vick Jason H.
Young Brian K.
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