Objective Quality Comparison of 4K UHD and Up-Scaled 4K UHD Videos

In this paper, we perform objective quality comparison between 4K ultra-high definition (UHD) and up-scaled 4K UHD videos. We aim at investigating added values of 4K UHD over high definition (HD). We examine the quality of the two types of videos at the same bitrate conditions for two compression standards, AVC and HEVC. Using our own 4K UHD video data, we generate test sequences having various quality levels and bitrates using AVC and HEVC. Objective quality comparison is performed using multi-scale structural similarity (MS-SSIM), visual information fidelity (VIF), and visual signal-to-noise ratio (VSNR) metrics. The results show that superiority between the two UHD versions changes according to the bitrate, where content characteristics and the codec also have notable influences.