Subjective-Driven Complexity Control Approach for HEVC

The latest High Efficiency Video Coding (HEVC) standard significantly increases the encoding complexity for improving its coding efficiency, compared with the preceding H.264/Advanced Video Coding (AVC) standard. In this paper, we present a novel subjective-driven complexity control (SCC) approach to reduce and control the encoding complexity of HEVC. Through reasonably adjusting the maximum depth of each largest coding unit (LCU), the encoding complexity can be reduced to a target level with minimal visual distortion. Specifically, the maximum depths of different LCUs can be varied through solving the proposed optimization formulation of complexity control, based on two explored relationships: 1) the relationship between the maximum depth and encoding complexity and 2) the relationship between the maximum depth and visual distortion. Besides, the subjective visual quality is favored with a novel subjective-driven constraint imposed in the formulation, on the basis of a visual attention model. Finally, the experimental results show that our approach can achieve a wide range of encoding complexity control (as low as 20%) for HEVC, with the smallest complexity bias being 0.2%. Meanwhile, our SCC approach outperforms other two state-of-the-art complexity control approaches, in terms of both control accuracy and visual quality.