Patent ID: 7778460
Filing Date: 2010-08-17
Classification: H04N

Abstract:
1. An apparatus for detecting a color tone pattern of an input image signal, the apparatus comprising: a pattern detector outputting a pattern detection signal by comparing a difference between image signal values of each of one or more pixels with a predetermined comparison value in an activated area of one frame of the input image signal or a predetermined area of the activated area, wherein if a maximum difference between image signal values of each pixel is less than the predetermined comparison value, the pattern detector outputs a pattern detection signal indicating that the image signal is a gray pattern, and if the maximum difference between the image signal values of each pixel is greater than the predetermined comparison value, the pattern detector outputs a pattern detection signal indicating that the image signal is a color pattern, wherein the pattern detector comprises: a first color tone pattern detector outputting a first pattern detection signal by comparing a difference between image signal values of each pixel with a first predetermined comparison value in the activated area of one frame of the input image signal or the predetermined area of the activated area; a second color tone pattern detector outputting a second pattern detection signal by comparing a difference between image signal values of a first pixel and image signal values of a second pixel neighboring the first pixel with a second predetermined comparison value in the activated area of the frame of the input image signal or the predetermined area of the activated area; and a third color tone pattern detector receiving the first and second pattern detection signals and performing an AND operation on the two pattern detection signals, wherein the first color tone pattern detector outputs the first pattern detection signal indicating that the image signal is a gray pattern if a maximum difference between the image signal values of each pixel is less than the first predetermined comparison value and outputs the first pattern detection signal indicating that the image signal is a color pattern if the maximum difference between the image signal values of each pixel is greater than the first predetermined comparison value, the second color tone pattern detector outputs the second pattern detection signal indicating that the image signal is the gray pattern if a maximum difference between the image signal values of the neighboring pixels is less than the second predetermined comparison value and outputs the second pattern detection signal indicating that the image signal is the color pattern if the maximum difference between the image signal values of the neighboring pixels is greater than the second predetermined comparison value, and the third color tone pattern detector outputs a third pattern detection signal indicating that the image signal is the gray pattern if the first and second pattern detection signals indicating that the image signal is the gray pattern are input from the first and second color tone pattern detectors and outputs the third pattern detection signal indicating that the image signal is the color pattern if the first or second pattern detection signal indicating that the image signal is the color pattern is input from the first or second color tone pattern detectors.