Modelling visual attention and motion effect for visual quality evaluation

The perceptual visual quality evaluation of human visual system (HVS) is very complex. It concerns almost all aspects of visual processing in the vision path, from low-level neuron activities to high-level visual perception. Existing perceptual visual quality metrics (VQMs) only considered several of the mechanisms of HVS, and many others are ignored. In this paper, two global modulatory factors, visual attention and motion suppression, are modelled and combined to form a mathematic expression - perceptual quality significant level (PQSL). To a certain extent, it is believed that PQSL values reflect the processing ability of the human brain on local visual content. To evaluate their effects on visual quality evaluation, two VQMs are proposed. One is a MSE-like VQM based in a PQSL-modulated JND profile, which was proposed in (Z. K. Lu et al, Proc. ICASSP´2004, v.3, p.705-708, 2004); the other VQM is based on Wang´s visual quality assessment (Sig. Proc.:Image Comm., v.19, n.2, p.121-132, 2004), PQSL values are used to adjust the weights of his structural similarity index. Experimental results show that introduction of the global modulatory factors can improve the performance of current visual quality metrics.