MDCP: Patent Abstact US05166686: Variable length block coding with changing characteristics of input samples

US05166686 Variable length block coding with changing characteristics of input samples

Assignee NEC Corporation

Assign./Filed Nov. 24, 1992/ June 29, 1990

Inventors Sugiyama; Akihiko

Summary Transform coding with adaptable input block size.

Abstract In a communications system, input digital samples are continuously stored into a buffer and successively divided into a group of blocks of different lengths. The samples of each of the blocks are encoded into linear transform coefficients at intervals corresponding to the length of each block and each block of the linear transform coefficients is then decoded into a variable length block of decoded samples. An error between each block of decoded samples and a corresponding block of samples from the buffer is detected, and a plurality of such errors derived from each group of blocks of input samples are stored in memory. A minimum value of the errors in the memory is determined and one of the blocks of the coded symbols which corresponds to the minimum value is identified as having an optimum block length. The linear transform coefficients of the optimum block length are multiplexed with the optimum block length information into a channel for transmission. At the receive end of the system, the transmitted linear transform coefficients are decoded into original signal at intervals corresponding to the multiplexed optimum block length information.

US05166686	Variable length block coding with changing characteristics of input samples
Assignee	NEC Corporation
Assign./Filed	Nov. 24, 1992/ June 29, 1990
Inventors	Sugiyama; Akihiko
Summary	Transform coding with adaptable input block size.
Abstract	In a communications system, input digital samples are continuously stored into a buffer and successively divided into a group of blocks of different lengths. The samples of each of the blocks are encoded into linear transform coefficients at intervals corresponding to the length of each block and each block of the linear transform coefficients is then decoded into a variable length block of decoded samples. An error between each block of decoded samples and a corresponding block of samples from the buffer is detected, and a plurality of such errors derived from each group of blocks of input samples are stored in memory. A minimum value of the errors in the memory is determined and one of the blocks of the coded symbols which corresponds to the minimum value is identified as having an optimum block length. The linear transform coefficients of the optimum block length are multiplexed with the optimum block length information into a channel for transmission. At the receive end of the system, the transmitted linear transform coefficients are decoded into original signal at intervals corresponding to the multiplexed optimum block length information.