Qualitative DC Mode Conditions for Fast Intra Prediction Mode Decision in H.264/AVC

In this paper, we present a simple but efficient algorithm for intra prediction mode decision in H.264/AVC. Based on our investigation, the DC mode appears to be the superior prediction mode among various candidates. We propose an intra-mode decision algorithm where the DC mode is chosen as a candidate for the best prediction mode. Our experimental results show that the proposed algorithm saves 80.82% of the encoding time, compared to the H.264 reference software on average, while reducing the negligible peak signal-to-noise ratio (PSNR) values and slightly increasing the bitrate. In order to reduce the bitrate increment of the above-mentioned algorithm and refine our DC mode condition, we propose another fast intra prediction mode decision algorithm where we use a condition of block boundary to select the DC mode. Our experimental results show that this proposed algorithm not only increases PSNR values and decreases bitrates, but also saves the encoding time.