M.: Estimation of subjective quality for mixed-resolution stereoscopic video

ABSTRACT In mixed-resolution (MR) stereoscopic video, one view is presented with a lower resolution compared with the other one; therefore, a lower bitrate, a reduced computational complexity, and a decrease in memory access bandwidth can be expected in coding. The human visual system is known to fuse left and right views in such a way that the perceptual visual quality is closer to that of the higher-resolution view. In this paper, a subjective assessment of mixed resolution (MR) stereoscopic videos is presented and the results are analyzed and compared with previous subjective tests presented in the literature. Three downsampling ratios 1/2, 3/8, and 1/4 were used to create lower-resolution views. Hence, the lowerresolution view had different spatial resolutions in terms of pixels per degree (PPD) for each downsampling ratio. It was discovered that the subjective viewing experience tended to follow a logarithmic function of the spatial resolution of the lowerresolution view measured in PPD. A similar behavior was also found from the results of an earlier experiment. Thus, the results suggest that the presented logarithmic function characterizes the expected viewing experience of MR stereoscopic video