United States Patent 7,620,258
Chen , et al. November 17, 2009

Extended amplitude coding for clustered transform coefficients


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

Full patent text at USPTO