Patent ID: 6643410
Filing Date: 2003-11-04
Classification: G06T,H04N

Abstract:
A method of determining the extent of blocking artifacts in a digital image formed of rows and columns of pixels, comprising the steps of:a) forming a column difference image from the difference between columns in the digital image; b) averaging the values in the columns in the column difference image to produce a column difference array; c) computing the average of the values in the column difference array that are separated by one block width to produce a block averaged column difference array; d) locating a peak value in the block averaged column difference array; e) calculating a mean value of the block averaged column difference array excluding the peak value to produce a column base value; f) computing the ratio between the peak value and the column base value to produce a column ratio; g) repeating steps a)-f) in the row direction to produce a row ratio; and; h) employing the column and row ratios as a measure of the extent of blocking artifacts in the digital image.