Patent ID: 6999203
Filing Date: 2006-02-14
Classification: H04N

Abstract:
1. A circuit for multi-bit processing of a gray scale image in a printer, comprising: a divider for converting the gray component value of each pixel in a multi-bit image into a resolution of a printer to output a first value; a remainder calculator for converting the gray component value of each pixel in a multi-bit image into the resolution of the printer, to output a second value; a half-tone table for storing half tone values corresponding to thresholds for pixels; a comparator for comparing the remainder with a corresponding threshold half tone value received from the half-tone table and outputting a binary bit according to the comparison result; a position controller for controlling the half-tone table to repeatedly output the threshold half tone value of each pixel; an adder for adding the quotient received from the divider to the gray component of the binary processed output of the comparator, pixel by pixel and outputting a multi-bit dithered image; and a pulse width modulator for modulating the multi-bit dithered image received from the adder to different pulse widths according to the gray components of the pixels of the multi-bit dithered image and controlling the modulated image to be printed in dots of different sizes.