Adaptive compression coding

Author

Nasiopoulos, Panos ; Ward, Rabab K. ; Morse, Daryl J.

Author_Institution

Vancouver Community Coll., BC, Canada

Volume

39

Issue

8

fYear

1991

fDate

8/1/1991 12:00:00 AM

Firstpage

1245

Lastpage

1254

Abstract

A compression technique which preserves edges in compressed pictures is developed. The proposed compression algorithm adapts itself to the local nature of the image. Smooth regions are represented by their averages and edges are preserved using quad trees. Textured regions are encoded using BTC (block truncation coding) and a modification of BTC using look-up tables. A threshold using a range which is the difference between the maximum and the minimum grey levels in a 4×4 pixel quadrant is used. At the recommended value of the threshold (equal to 18), the quality of the compressed texture regions is very high, the same as that of AMBTC (absolute moment block truncation coding), but the edge preservation quality is far superior to that of AMBTC. Compression levels below 0.5-0.8 b/pixel may be achieved

Keywords

data compression; encoding; picture processing; BTC; adaptive compression coding; block truncation coding; compressed pictures; edge preservation quality; grey levels; local nature; look-up tables; quad trees; smooth regions; texture regions; Aerospace engineering; Aircraft propulsion; Biomedical engineering; Compression algorithms; Helium; Image coding; Image edge detection; Military aircraft; Quantization; Robot vision systems;

fLanguage

English

Journal_Title

Communications, IEEE Transactions on

Publisher

ieee

ISSN

0090-6778

Type

jour

DOI

10.1109/26.134014

Filename

134014