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:
Oct. 19, 2004
Filed:
Jul. 08, 1999
ATI International SRL, Christchurch, BB;
Abstract
A method and apparatus for compressing image data for storage in a memory device is presented. This is accomplished by separating the image data into a plurality of pixel sets where each pixel set is of a predetermined pixel set size. A discrete cosine transform is then performed on each of the pixel sets to produce a plurality of transform coefficients. These transform coefficients are then compressed to produce a compressed data set. Compressing the transform coefficients preferably includes determining a coefficient set that includes a portion of the transform coefficients that reasonably approximate the pixel set. These coefficients are then mapped to known ranges such that a limited number of bits can encode values throughout these predetermined ranges. The mapped coefficients resulting from the mapping step are then manipulated to fit within a limited number of bits assigned to each coefficient. The limited number of bits is determined partially based on the coefficient set to be compressed. The manipulation of these mapped coefficients is preferably accomplished by shifting, rounding, and truncating the mapped coefficients. The coefficients resulting from these operations are then packed along with coefficient identifying information to form the compressed data set.