United States Patent | 7,620,258 |
Chen , et al. | November 17, 2009 |
Extended amplitude coding for clustered transform coefficients
Abstract
Coding quantized transform coefficients as occur in image compression combines a position coding method to code the position of clusters of consecutive non-zero-valued coefficients with an amplitude coding method to code the amplitudes of a concatenation of a plurality of the clusters. The amplitude coding method exploits that runs of amplitude 1 coefficients are more likely in the clusters than runs of other coefficient amplitudes.
Inventors: | Chen; Wen-hsiung (Sunnyvale, CA), Toebes; John A. (Cary, NC) |
Assignee: | Cisco Technology, Inc. (San Jose, CA) |
Appl. No.: | 11/270,138 |
Filed: | November 9, 2005 |