A method includes calculating a mean of a plurality of pixels of a motion window, calculating a pixel amount of pixels similar to a center pixel, calculating a variance of the pixels, determining whether a difference between the center pixel and the mean is greater than a first predetermined value, determining whether the pixel amount similar to the center pixel is greater than a second predetermined value if the difference between the center pixel and the mean is not greater than the first predetermined value, determining whether the variance is smaller than a threshold value if the pixel amount similar to the center pixel is not greater than the second predetermined value, and filtering the center pixel according to a result of determining whether the variance is smaller than the threshold value. Finally, temporal weighted mean filters involving motion estimation are used for motion compensation in images after spatial filtering.