Weighted-to-Spherically-Uniform Quality Evaluation for Omnidirectional Video
Weighted-to-Spherically-Uniform Quality Evaluation for Omnidirectional Video
复制标题
全向视频的加权球面均匀质量评估
DOI：
10.1109/lsp.2017.2720693
复制
发表时间：
2017-09-01
影响因子：
3.9
通讯作者：
Yu, Lu
中科院分区：
文献类型：
--
作者：
Sun, Yule;Lu, Ang;Yu, Lu
全方位视频记录围绕一个中心位置的所有方向的场景。它允许用户在所有方向上自由选择观看内容。假设观察方向均匀分布，各向同性的观察空间可以被视为一个球体。全向视频通常由具有一个或多个平面的不同投影格式表示。为了更准确地测量全方位视频在观测空间的客观质量，本文提出了一种加权球均匀质量评价方法。该算法将投影平面上每个像素点的误差乘以一个权值，以保证观测空间中的等效球面面积，使得映射球面面积相等的像素点对畸变测量的影响相同。该方法避免了由恢复表示空间向观测空间转换所引起的误差传播，使得质量评价结果更加准确可靠。作为这种质量评价方法的一个例子，加权球形均匀峰值信噪比的描述和它的性能进行了实验分析。
Omnidirectional video records a scene in all directions around one central position. It allows users to select viewing content freely in all directions. Assuming that viewing directions are uniformly distributed, the isotropic observation space can be regarded as a sphere. Omnidirectional video is commonly represented by different projection formats with one or multiple planes. To measure objective quality of omnidirectional video in observation space more accurately, a weighted-to-spherically-uniform quality evaluation method is proposed in this letter. The error of each pixel on projection planes is multiplied by a weight to ensure the equivalent spherical area in observation space, in which pixels with equal mapped spherical area have the same influence on distortion measurement. Our method makes the quality evaluation results more accurate and reliable since it avoids error propagation caused by the conversion from resampling representation space to observation space. As an example of such quality evaluation method, weighted-to-spherically-uniform peak signal-to-noise ratio is described and its performance is experimentally analyzed.