Verification testing of HEVC compression performance for UHD video

This paper presents results and analysis of a compression performance test carried out within standardization activities for the HEVC standard (ITU-T H.265 and ISO/IEC 23008-2) with the focus on UHD video content. The analysis is based on subjective tests, and the performance of the new standard is compared with its predecessor AVC (ITU-T H.264 and ISO/IEC 14496-2). The Degradation Category Rating test methodology was used in a controlled laboratory environment. The test showed that a bit rate savings of more than 50 % can be achieved by HEVC for the same perceived video quality (with the tested encoding algorithms). In the high-quality coding range, an average measured bit rate savings of 60 % is reported. These results are higher than the bit rate savings measured using the PSNR objective quality metric. However, it has been shown that the bit rates required to achieve good quality of compressed content, as well as the bit rate savings relative to AVC, are highly dependent on the characteristics of the underlying UHD content. Additional analysis is presented to explain the measured results and show their dependency on the measurement metric, viewing distance, and the range of considered bit rates.