Patent ID: 7265736

Claim:
An apparatus for reducing false contour in a digital display panel, the apparatus comprising: a data converter, which processes an image signal such that a gray level of the image signal exists within a predetermined range; an error diffuser, which diffuses an error between a gray level of a current pixel in a current frame of the image signal received from the data converter and a gray level of the current pixel in the current frame after being subjected to gray-level change, to pixels adjacent to the current pixel in the current frame; a first gray-level changing unit, which receives the image signal from the error diffuser, calculates a difference in a gray level between each pixel in the current frame of the image signal and a pixel corresponding to the current frame pixel in a previous frame of the image signal using a block of pixels, comprising a plurality of pixels, of predetermined size having the current frame pixel inside the block of pixels for the current frame and the previous frame, and changes the gray level of the current frame pixel based on the gray level difference such that transition in an emission pattern of higher weighted subfields among subfields, which illuminate according to the gray level of the current frame pixel, between the current frame pixel and the previous frame pixel is minimized; and a subfield converter, which converts a subfield according to a gray level output from the first gray-level changing unit.