MNR: a novel approach for temporal filtering of MPEG distortions

As TV screens get ever larger, viewer tolerance to noise and artefacts has steadily declined. For next generation TVs such as flat TV, LCoS (liquid crystal on silicon), etc, being excellent in picture quality becomes a distinguishing feature. Although the quality of most digital signals has significantly been improved, distortion and noise still creep in and are an important source of picture degradations. Post-processing is a sensible solution that achieves a visual enhancement of the reconstructed images. Some of the artefacts, such as blocking and ringing, have already been widely considered. Therefore, this paper concentrates on a novel post-processing technique, that reduces another kind of distortion known as "mosquito noise". This temporal "busyness" is discarded by applying an adaptive temporal filter that preserves sharpness and naturalness of the reconstructed video signal in the frequency domain. The proposed algorithm is effective and straightforward to implement: experimental results show that the presented temporal post-filtering process significantly improves the visual quality of video. Moreover, the architectural options allow flexibility and cost trade-off.