Fast macroblock mode selection based on motion content classification in H.264/AVC

In H.264/AVC, new coding techniques introduce many optional macroblock encoding modes. Exhaustive search over all possible modes can achieve optimal coding efficiency but is highly computationally expensive. In this paper, a fast macroblock mode selection (FMMS) algorithm based on the motion content classification is proposed. Each macroblock is categorized into complex motion or simple motion contents by a fuzzy classifier, then different mode search orders with distinct early termination schemes are employed according to the classification. The proposed method can be readily incorporated with fast motion estimation algorithms and simulation results show that it can further save 40%-70% of the block distortion calculations on the basis of conventional fast motion estimation algorithms, while maintaining similar rate distortion performance.