Patent ID: 7031546
Filing Date: 2006-04-18
Classification: G06T

Abstract:
1. A noise reduction method for the decoded signal of a digitally compressed image signal, comprising: a gradient calculation step of obtaining a predetermined gradient in an area of vertical M×horizontal N pixels (M and N are positive integers) around a notice pixel, a difference value calculation step of calculating, in an area of vertical J×horizontal K pixels (J and K are positive integers satisfying the relationships of J≦M and K≦N, respectively) around said notice pixel, (J×K−1) difference values between said notice pixel and pixels other than said notice pixel, a correction value calculation step of calculating correction values from said gradient obtained by said gradient calculation step and said (J×K−1) difference values obtained by said difference value calculation step, and an addition step of calculating a new notice pixel by adding said correction values to said notice pixel.