A temporal just-noticeble distortion profile for video in DCT domain
Just-noticeable distortion (JND) profile is an efficient model to represent the perceptual redundancies. Human eyes usually are not sensitive to the distortion below the JND threshold. In order to extend the spatial JND profile to video images by considering the temporal effects, a temporal JND modulation factor is introduced in this paper, which not only incorporates the temporal contrast sensitivity function (CSF) and the smooth pursuit eye movement (SPEM), but also considers the directionality of the motion in video sequences. This factor can be easily combined with other existing subband spatial JND models to achieve a complete spatio-temporal JND profile. Experimental results show that the proposed model is consistent with the human visual system (HVS). Compared with the other JND profiles, the proposed model can tolerate more distortion and has much better perceptual quality at the same time. Since the proposed JND model is DCT based, it can be easily applied in many related areas, such as compression, watermarking, error protection, perceptual distortion metric, and so on.