Zigzag line discrete cosine transform for blocking artifact removal

A new pre-processing approach for the removal of the blocking effect, associated with the standard 2D-DCT, is introduced in this paper. In this method, the processing of the image is started from the top corners by zigzagging rows and columns of an image into horizontal, vertical or diagonal streams of pixels. These pixel streams are transformed into one-dimensional line arrays. The one-dimensional DCT transform is applied to each array. The experimental results reveal the effectiveness of this method in reducing the blocking effect associated with the standard DCT. The zigzag line method produces very good subjective as well as PSNR results.