Ringing artefact reduction using adaptive averaging filtering

Abstract

The ringing arteJuct e.rist.7 not only in the encoded images by JPEG and JPEG 2000. hut aka in the encoded video .sequences by MPEG-I MPEG-2, and MPEG4. Based on the unalyis ofthe profile of tlte encoded image, an adaptive averaging,filtering techniqlie is proposed in this paper. An edge detrction operator is wed in extracting the edges in an image. BV nsing the edge infortnation. an averaging filrr i.7 applied to onlv the pi.rels near edges bnt not on the edges. Experimental resiilts show that the ringing arteJact can be reduced greatlv and overall image qitalih i s improved in terms of siibjective and objective criteria. The proposed filtering merhod is simple hiit effective. I t can be nsed together with DCT-bused or wavelet-based image or 'video compression system to improve the quality of decoded images. Index Terms Coding artefact reduction, image filtering, image processing, ringing artefact reduction.