Fast mode decision for h.264 intra prediction with prediction samples easy to generate

This paper presents a fast mode decision algorithm and its hardware structure for H.264/AVC intra prediction. For 4×4 luma blocks, the algorithm uses only 8 prediction samples to reduce the number of possible prediction modes from 9 to 4. The 8 prediction samples are easier to generate than original prediction samples used in the H.264/AVC intra prediction. Values of the 8 prediction samples are close to the values of the original prediction samples. For 16×16 luma and chroma blocks, the algorithm uses directions of each mode and it reduces the number of possible prediction modes from 4 to 2. Overall, the algorithm reduces the number of possible prediction modes from 17 to 8. Experimental results show that the algorithm has less degradation of peak signal-to-noise ratio than those of existing algorithms. The hardware structure for the algorithm reduces the computation time by performing the intra prediction for 4×4 luma blocks and the intra prediction for 16×16 luma blocks and chroma blocks in parallel.