Variable-length code decoding apparatus, variable-length code decoding method, and program

A computer, comprising:

• a code buffer configured to hold a variable-length code in which the same bit value continues for a given number of bits from the most significant bit;
• a plurality of code word detectors each of which is configured to read the variable-length code from said code buffer to detect whether or not the variable-length code matches a specified code word;
• a decoded code word determination block configured to determine a code word decoded, based on detection results of said plurality of code word detectors;
• and
• a configuration information holding section configured to hold configuration information containing the specified code words to be detected in said plurality of code word detectors and code lengths of the specified code words as arranged in an ascending order of code length,
• wherein the computer executes an instruction to, in the configuration information, recover one or more of the code lengths that are defined by a difference from another one of the code lengths, and recover the given number of consecutive bits of the same bit value in accordance with the code length, based on one bit held for the bit value that continues for the given number of bits, and thereafter cause said plurality of code word detectors to perform the detection.

A program for causing a computer that includes

• a code buffer configured to hold a variable-length code in which the same bit value continues for a given number of bits from the most significant bit,
• a plurality of code word detectors each of which is configured to read the variable-length code from the code buffer to detect whether or not the variable-length code matches a specified code word,
• a decoded code word determination block configured to determine a code word decoded, based on detection results of the plurality of code word detectors, and
• a configuration information holding section configured to hold configuration information containing the specified code words to be detected in the plurality of code word detectors and code lengths of the specified code words as arranged in an ascending order of code length,
• the program, comprising the steps of:
• in the configuration information, recovering one or more of the code lengths that are defined by a difference from another one of the code lengths;
• in the configuration information, recovering the given number of consecutive bits of the same bit value in accordance with the code length, based on one bit held for the bit value that continues for the given number of bits;
• and
• causing the plurality of code word detectors to perform the detection.

A variable-length code decoding method employed in a variable-length code decoding apparatus that includes

• a code buffer configured to hold a variable-length code in which the same bit value continues for a given number of bits from the most significant bit,
• a plurality of code word detectors each of which is configured to read the variable-length code from the code buffer to detect whether or not the variable-length code matches a specified code word,
• a decoded code word determination block configured to determine a code word decoded, based on detection results of the plurality of code word detectors, and
• a configuration information holding section configured to hold configuration information containing the specified code words to be detected in the plurality of code word detectors and code lengths of the specified code words as arranged in an ascending order of code length,
• the method comprising the steps of:
• in the configuration information, recovering one or more of the code lengths that are defined by a difference from another one of the code lengths;
• in the configuration information, recovering the given number of consecutive bits of the same bit value in accordance with the code length, based on one bit held for the bit value that continues for the given number of bits;
• and
• causing the plurality of code word detectors to perform the detection.