Asymmetric coding of stereoscopic 3D based on perceptual significance
Résumé
Asymmetric stereoscopic coding is a very promising technique to decrease the bandwidth required for stereoscopic 3D delivery. However, one large obstacle is linked to the limit of asymmetric coding or the just noticeable threshold of asymmetry, so that 3D viewing experience is not altered. By way of subjective experiments, recent works have attempted to identify this asymmetry threshold. However, fixed threshold, highly dependent on the experiment design, do not allow to adapt to quality and content variation of the image. In this paper, we propose a new non-uniform asymmetric stereoscopic coding adjusting in a dynamic manner the level of asymmetry for each image region to ensure unaltered binocular perception. This is achieved by exploiting several HVS-inspired models; specifically we used the Binocular Just Noticeable Difference (BJND) combined with visual saliency map and depth information to quantify precisely the asymmetry threshold. Simulation results show that the proposed method results in up to 44% of bitrate saving and provides better 3D visual quality compared to state-of-the-art asymmetric coding methods.