New Appraisal Method for Blocking Effects in Subimage Coding

Considering the human visual masking property, a modified relationship between the activity function and the visibility threshold is developed. This leads to a novel objective appraisal method for blocking effects in a lossy subimage coding by virtue of the human visual sensitivity. The appraisal criterion is examined using a series of reconstructed images that are DCT-coded at various bit rates. Experimental results show that the presented blocking effect measure well agrees with the subjective ranking.