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Analysis of H.265/HEVC, H.264 and VP9 coding efficiency based on video content complexity

The main goal of this paper is to find the relationship between video content complexity and the objective quality, further to compare H.265/HEVC, H.264/AVC, and VP9 encoders in three modes based on complexity of the video content. There are three evaluation metrics: Peak Signal to Noise Ratio (PSNR), structural similarity (SSIM), and encoding time, which were introduced to compare the three video encoders comprehensively. Each video sequence has 250 frames, and their resolution is 1920×1080, differing in spatial and temporal complexity. An extensive range of video content complexity were selected in the video sequences. Objective quality evaluation based on the calculation of spatio-temporal activities is tested to validate its suitability as video content complexity indicator in quality assessment. According to the analysis of experiment results, all the encoded modes present an obvious same trend. On a fixed video resolution and bit rate, with the video complexity increasing, the objective quality is decreasing and the encoding times is increasing. It was also concluded that the objective quality of X265-slow is far better than other encoder modes of X264 and VP9. In terms of encoding time, the encoding time of H264 was shown to be less than both HEVC and VP9.