Perceptually Driven Nonuniform Asymmetric Coding of Stereoscopic 3D Video
Asymmetric stereoscopic video coding has already proven its effectiveness in reducing the bandwidth required for stereoscopic 3D delivery without degrading the visual quality. This approach, in which the left and right views are encoded with different levels of quality, relies on the perceptual theory of binocular suppression. However, to ensure comfortable 3D viewing, the just-noticeable level of asymmetry, i.e., the maximum quality gap between views, has to be carefully defined. Both subjectively and empirically fixed thresholds of asymmetry demonstrated either the maladjustment to content or dependency to the experimental design. This paper describes a new nonuniform asymmetric stereoscopic video coding method adaptively adjusting the level of asymmetry for each region of the image based on its perceptual significance. The proposed method uses a fully automated model that dynamically determines the best bounds of asymmetry for which the 3D viewing experience will not be altered. This is achieved by exploiting several human-visual-system-inspired models, namely, the binocular just-noticeable difference, and the visual saliency map and depth information. The simulation results show that the proposed method results in bit rate saving of up to 26% and provides better 3D visual quality compared with state-of-the-art asymmetric coding methods.