  As the immersive multimedia techniques like Free-viewpoint TV (FTV) develop
at an astonishing rate, user's demand for high-quality immersive contents
increases dramatically. Unlike traditional uniform artifacts, the distortions
within immersive contents could be non-uniform structure-related and thus are
challenging for commonly used quality metrics. Recent studies have demonstrated
that the representation of visual features can be extracted from multiple
levels of the hierarchy. Inspired by the hierarchical representation mechanism
in the human visual system (HVS), in this paper, we explore to adopt structural
representations to quantitatively measure the impact of such structure-related
distortion on perceived quality in FTV scenario. More specifically, a
bio-inspired full reference image quality metric is proposed based on 1)
low-level contour descriptor; 2) mid-level contour category descriptor; and 3)
task-oriented non-natural structure descriptor. The experimental results show
that the proposed model outperforms significantly the state-of-the-art metrics.
