Patent ID: 6658159
Filing Date: 2003-12-02
Classification: H04N

Abstract:
A method for compressing image data, comprising the steps of:decomposing the image data into code-blocks of coefficients using a transform, each code-block comprising a plurality of bit-planes from a most significant bit-plane to a least significant bit-plane; processing bit-planes of coefficient data in the code blocks in multiple coding passes to generate raw bit-plane data; arithmetically coding a portion of raw bit-plane data to generate arithmetically coded data; and writing the arithmetically coded data and the raw bit-plane data not arithmetically coded directly into a bit-stream; wherein raw bit-plane data generated during significance propagation and magnitude refinement coding passes for bit-planes p0âˆ’K is written directly into the bit-stream, wherein p0 denotes the most significant bit-plane of a code block in which any sample therein becomes contextually significant during arithmetic coding and K is an integer parameter.