Stereoscopic image coding: Effect of disparate image-quality in left- and right-eye views

摘要

The present research assessed the subjective image-quality of stereo sequences where the left- and right-eye views differed in severity of compression. Viewers watched image sequences where the left-eye view was displayed at a higher quality than the right-eye view, and rated the combined overall subjective image-quality of the sequence. Three stereo image sequences were used for assessment. Each sequence, in the ITU-R 601 format, was 10 s in duration and the images for the left-eye view were coded independently of the right-eye view, at bit-rates of 6, 3, 2 and 1 Mbits/s, using MPEG-2, Main Profile/Main Level syntax. These were combined to generate stereo sequences where the bit-rates were (left : right) 6 : 6, 6 : 3, 6 : 2, 6 : 1, 3 : 3, 3 : 2 and 3 : 1. The resulting stereo sequences were viewed by 26 subjects, and rated in terms of subjective image-quality. The rating methodology was based on the double-stimulus continuous-quality scale method described in ITU-R Recommendation 500. The results showed that the subjective quality of a stereo image sequence fell approximately midway between the quality of the left- and right-eye views. The results are consistent with known properties of binocular vision, in particular with the averaging of brightness and contrast of stimuli presented to the two eyes.