Method and system for compressing a pixel map signal using dynamic quantization

摘要

A pixel map signal is converted into a coefficient signal of block coefficient signals, each representing the pixels in a pixel map block (420) in a pixel map (410) with the coefficients in a hybrid polynomial. The coefficient signal is quantized by dividing each of the coefficient values in each of the block coefficient signals by quantization factors to produce quantized coefficient values which replace the coefficient values. Block coefficient signals which represent an edge block (424) in the pixel map (410) are divided by larger quantization factors than block coefficient signals which represent a center block (422) in the pixel map (410). As a result, smaller quantized coefficient values are obtained so that block coefficient signals which represent an edge block (424) are compressed to a greater extent than block coefficient signals that represent a center block (422) in the pixel map (410).