The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 20, 2005
Filed:
Nov. 14, 2001
Yu-ling Chen, Epping, AU;
Yu-Ling Chen, Epping, AU;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A method, an apparatus () and a computer program product for entropy coding of discrete wavelet transform (DWT) coefficient bits that are arranged into code blocks and coded in bitplane order using three coding passes for each bitplane are disclosed. In the method, transform coefficients of a code block () in sign-magnitude form are pre-analyzed. Statistical data about the coefficients is stored, preferably with the coefficients. Significance state data (), coded data (), magnitude refinement data (), bit data (), and sign data () for the code block are buffered. More preferably, the buffering is implemented using a FIFO (), located between a context generation module () and an arithmetic coder (). Based upon the statistical data, at least one command for at least one sequence of bit and context pairs is generated for arithmetic encoding.