Detection methods for blocking artefacts in transform coded images

In block discrete cosine transform-based image compression, the blocking artefacts are the main cause of degradation, especially at higher compression ratio. It is of interest to be able to numerically assess the degree of blocking artefacts as it plays an important role in the design, optimisation and assessment of image and video coding systems. In this work, comparison of novel algorithms based on different modelling functions for blocking artefact detection in compressed images is proposed. The authors´ experiment results show that for all types of images, the proposed methods detect blocking artefacts more accurately as compared with other post-processing methods/techniques and is very efficient and stable since the signal need not be compressed/decompressed.