Patent ID: 9147377
Filing Date: 2015-09-29
Classification: G03F,G06F,G09G,H01J

Abstract:
1. A method for image dithering, comprising: providing a polygon related to an integrated circuit (IC) layout design in a graphic database system (GDS) grid; converting the polygon to an intensity map in the GDS grid, the intensity map including a group of partial pixels corresponding to pixels partially covered by the polygon and a group of full pixels corresponding to pixels fully covered by the polygon; performing a first quantization process to a partial pixel to one of n-bit discrete intensity levels to determine a first error; applying the first error to one or more full pixels from among the group of full pixels while excluding pixels from among the group of partial pixels; performing a second quantization process to a full pixel from among the group of full pixels to one of the n-bit discrete intensity levels to determine a second error; and distributing the second error to one or more full pixels from among the group of full pixels while excluding pixels from among the group of partial pixels.