Patent Document ID: 9848105
Application ID: 09080700
Patent Status: 1

Claim One:
1. A method of quantizing pixels of a color image, wherein consecutively for each pixel steps of the method comprise: summing an input for the pixel with error generated from other pixels in a neighborhood of the pixel to generate a modified input for the pixel; determining an output for the pixel according to equations 1 and 2; b ⁡ ( k ) = { 1 , for ⁢ ⁢ i * ( k ) ≥ 1.5 + d ; 0 , for ⁢ ⁢ i * ( k ) < - 0.5 - d ; undetermined , for ⁢ - 0.5 - d ≤ i * ( k ) < 1.5 + d ; ( 1 ) d ≥ - 1.0 ; ( 2 ) wherein k represents color components in a device color space, b(k) and i*(k) are the output and modified input respectively for the color component k, and d is a preset threshold; determining the output for the pixel by applying vector quantization to the modified input when the output for a color component is undetermined from equations 1 and 2, wherein colors corresponding to color components already determined are excluded from the vector quantization; and generating error for summing with successive inputs, the error representative of a difference between the modified input and the output, wherein a color image is rendered based on the determined output for each pixel.