Windowed encoding of spatially coupled LDGM codes for lossy source compression
Document Type
Conference Proceeding
Publication Date
8-10-2016
Abstract
Recently, it has been shown that a class of spatially coupled low-density generator-matrix (SC-LDGM) code ensembles displays distortion saturation for the lossy binary symmetric source coding problem with the belief propagation guided decimation (BPGD) algorithm, i.e., the BPGD distortion approaches the optimal expected distortion of the underlying ensemble asymptotically in code length. Here, we investigate the distortion performance of a practical class of protograph-based SC-LDGM code ensembles and demonstrate distortion saturation numerically. Moreover, we propose an efficient windowed encoding (WE) algorithm that takes advantage of the convolutional structure of the SC-LDGM codes. By using the WE algorithm, a distortion very close to the rate-distortion limit can be achieved for a fixed compression rate with low-to-moderate encoding latency.
Identifier
84985911939 (Scopus)
ISBN
[9781509018062]
Publication Title
IEEE International Symposium on Information Theory Proceedings
External Full Text Location
https://doi.org/10.1109/ISIT.2016.7541666
ISSN
21578095
First Page
2084
Last Page
2088
Volume
2016-August
Grant
CCF-1439465
Fund Ref
National Science Foundation
Recommended Citation
Golmohammadi, Ahmad; Mitchell, David G.M.; Kliewer, Jorg; and Costello, Daniel J., "Windowed encoding of spatially coupled LDGM codes for lossy source compression" (2016). Faculty Publications. 10339.
https://digitalcommons.njit.edu/fac_pubs/10339
