中文摘要：

H．264／AVC视频编码在空域上从多个方向进行多种模式的帧内预测，并使用率失真优化（RDO）算法选择最佳模式，使其算法复杂度很高，无法满足实时视频的需求。为此，提出一种快速预测算法，利用宏块在一定方向上的像素差分和对宏块是否有明显纹理及纹理方向进行有效预判，并根据预判结果对块类型和预测模式进行选择，避免对各块进行所有模式的计算，从而有效地降低了复杂度。实验结果表明本算法在峰值信噪比（PSNR）和码率变化极小的情况下，编码速度有显著提高。

英文摘要：

H.264/AVC provides several predicting modes and directions for intra prediction in the spatial region, and the optimal mode is selected by Rate Distortion Optimization（RDO） with high coding complexity. In order to solve this problem, a fast selective algorithm of intra prediction is proposed. The sum of the pixel difference in some direction is utilized to estimate the flatness and texture direction of a block. Then, with the results of this prediction, the block type and prediction mode are selected, in order to effectively reduce the computational complexity. Experimental results show that the proposed fast algorithm can achieve remarkable computation reduction while maintaining similar PSNR and bit rate performance.