Fast intra mode decision algorithm using sub-sampled pixels

Intra prediction is a significant technique in H.264/AVC reference software. However, it has heavy computational complexity. In order to solve this problem, many fast algorithms have been proposed. In this paper, we propose a fast intra mode decision algorithm which predicts the edge direction of the current block using sub-sampled pixels to reduce high computational complexity of the H.264/AVC encoder. The proposed algorithm shows that it not only improves the coding performance but also reduces the computational complexity of the H.264/AVC encoder. The experimental results show that the proposed algorithm achieves the encoding time reduction of 75.74% on an average with slight peak signal-to-noise ratio (PSNR) drop and bit-rate increment.