An Edge Detection Algorithm for the Fast Decision of H.264 Intra Mode.

• Main Authors: Jia-Wei Leng, 冷家偉
• Other Authors: 高立人
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/4wx4n7

碩士 === 國立臺北科技大學 === 電腦與通訊研究所 === 100 === 　　H.264 is the newest video coding standard. In order to achieve much higher coding efficiency than that of previously published standards, such as MPEG-1/2/4, H.261 and H.263, H.264 codec applies more complicated approaches in the coding procedure, such as integer Discrete Cosine Transformation, intra prediction, quarter-sample-accurate motion estimation, multiple reference frame and variable block-size, in inter prediction mode. Whiling having a better performance, the H.264 comes with the cost of highly increased complexity. Among all the processes, the intra and inter mode decision are the most complex parts in H.264 due to large amount of rate distortion cost have to be calculated for different prediction modes. In H.264, the optimal intra mode is decided based on a highly complex rate-distortion optimization process. For a macroblock, usually a number of 592 or 736 rate-distortion costs have to be calculated before the best prediction mode can be decided. To reduce the complexity, we propose in this paper a simple yet effective edge detection method so that the most probable prediction mode can be found. Moreover, we propose an adaptive algorithm so that a suitable number of prediction modes can be decided for the calculation of rate-distortion optimization inside the macroblock. Experimental results show that a very good trade off between the PSNR, bit-rate and run time performance can be achieved in the proposed approach.