Variable-length encoder and decoder using symbol/code-word re-association of a coding table

A variable-length encoder using symbol/code-word re-association of a code table comprising:

• delay means for delaying externally applied symbols;
• first storing means for storing a previously generated code table;
• first re-associating means for generating a re-associated code table and re-association information indicative of the relation between one of said symbols and a corresponding code word from said previously generated code table stored in said first storing means, based on a frequency of occurrence of the externally applied symbols during a predetermined time period, wherein said first re-associating means generates re-association information for each different one of the externally applied symbols;
• re-association information storing means for storing said re-associated code table and said re-association information, and sequentially outputting said re-association information;
• variable-length encoding means for receiving the delayed symbols and generating and sequentially outputting code words according to said re-associated code table stored in said re-association information storing means;
• and
• means for multiplexing and outputting said re-association information output from said re-association information storing means, and said code words output from said variable-length encoding means in an alternating manner.

A variable-length decoder for decoding output from a variable-length encoder using symbol/code-word re-association of a code table, the encoder having a previously generated code table stored in a code table, and which outputs data including code words and symbol/code-word re-association information, the decoder comprising:

• storing means for storing the same code table as that previously generated and stored in the variable-length encoder;
• demultiplexing means for receiving data output from the variable-length encoder, and dividing and outputting symbol/code-word re-association information and code words from the received data, wherein the symbol/code word re-association information for one of the code words is received only when the code word is received for the first time during a predetermined time interval and before another code word is received;
• re-associating means for receiving said re-association information from said demultiplexing means, re-associating a code-word and a corresponding symbol, and storing said re-associated code table information;
• and
• variable-length decoding means for decoding the code words based on said code table information stored in said re-associating means to thereby generate a symbol.

A variable-length decoder for decoding output from a variable-length encoder using symbol/code-word re-association of a code table, the encoder having a previously generated code table stored in a code table, and which outputs data including code words and symbol/code-word re-association information, the decoder comprising:

• storing means for storing the same code table as that previously generated and stored in the variable-length encoder;
• demultiplexing means for receiving data output from the variable-length encoder, and dividing and outputting symbol/code-word re-association information and code words from the received data, wherein said code words and said symbol/code-word re-association information are received in an alternating manner, and symbol/code-word re-association information for any one of the code words is received before said code words are received;
• re-associating means for receiving said re-association information from said demultiplexing means, re-associating a code word and a corresponding symbol when said code word is first received, and storing said re-associated code table information;
• and
• variable-length decoding means for decoding the code word based on the code table information stored in said re-associating means to thereby generate a symbol.

A variable-length encoding method, comprising:

• receiving input data;
• delaying the received input data for a pre-determined time period;
• counting occurrences of each distinct input data using the delayed input data;
• re-associating a relationship between code words and each distinct received input data based on the counted occurrence of each distinct input data, and generating re-association information for each distinct received input data, wherein the code words are read from a previously generated code book;
• encoding said received input data using the re-associated relationship and outputting selected code words;
• and
• transmitting said re-association information and the selected code words in an alternating manner.

A variable-length decoding method, comprising:

• receiving interleaved re-association information and code word data and separating said re-association information and said code word data;
• generating a re-associated code book by modifying association of code words and symbol data as defined in a previously generated code book using said re-association information;
• and
• decoding said received code word data using said re-associated code book and outputting decoded data.

A digital data transmission method, comprising:

• receiving input data;
• delaying the received input data for a pre-determined time period;
• counting occurrences of each distinct input data using the delayed input data;
• re-associating a relationship between code words and each distinct received input data based on the counted occurrence of each distinct input data, and generating re-association information for each distinct received input data, wherein the code words are read from a previously generated code book;
• encoding said received input data using the re-associated relationship and outputting selected code words;
• transmitting said re-association information and the selected code words in an alternating manner;
• receiving the re-association information and code word data and separating said re-association information and said code word data;
• generating a re-associated code book by modifying associations of code words and symbol data as defined in a previously generated code book using said re-association information;
• and
• decoding said received code word data using said re-associated code book and outputting decoded data.

A variable-length encoding method, comprising:

• receiving input symbol data;
• adapting a relationship between each distinct received input symbol data and variable-length code words and generating adapted association information for each distinct received input symbol data;
• generating a current code book, having a different association of code words and symbol data as compared to a previously generated code book, in accordance with said adapted association information;
• variable length coding said input symbol data into variable length code words using said current code book to generate variable length code words;
• and
• transmitting said adapted association information and said variable length code words in an alternating manner.

A variable-length decoding method, comprising:

• receiving interleaved adapted association information and code word data;
• generating a current code book, having a different association of code words and symbol data as compared to a previously generated code book, in accordance with said adapted information;
• and
• decoding said received code word data using said current code book and outputting decoded data.

A variable-length decoding method, comprising:

• receiving interleaved adapted association information and code word data;
• generating a current code book, having a different association of code words and symbol data as compared to a previously generated code book, in accordance with said adapted association information;
• and
• decoding said received code word data using said current code book and outputting decoded data.

A variable-length encoding method, comprising:

• receiving input symbol data;
• adapting a relationship between each distinct received input symbol data and variable-length code words and generating adapted association information for each distinct received input symbol data, wherein the adapted association information for a code word is received only when the code word data is received for the first time during a predetermined time interval and before another code word data is received;
• encoding said received input symbol data using a current code book, having a different association of code words and symbol data as compared to a previously used code book, in accordance with said adapted association information, to generate variable length code words;
• and
• transmitting said adapted association information and said variable length code words in an alternating manner.

A variable-length decoding method, comprising:

• receiving interleaved adapted association information and code word data;
• decoding said received code word using a code book, having a different association of code words and symbol data as compared to a previously used code book, in accordance with said adapted association indication information;
• and
• outputting said decoded code word data.