摘要
帧内预测模式选择是影响H.264编码速率的重要问题之一。H.264/AVC是从多个方向进行多种模式的帧内预测,使用率失真优化算法选择最佳模式,造成算法复杂度很高。在分析帧内预测模式快速算法研究现状的基础上,提出了一种新改进的算法;利用描述图像灰度分布信息的直方图作为判断图像平坦程度的依据,进而提出双阈值和邻近模式法;为了减少RD_Cost的计算量,再次提出双阈值,用来判定当前宏块的最有可能模式的有效性。经过大量的实验证明:该算法可以在基本保持图像质量和编码性能的情况下,使得帧内编码效率得到提高。
Mode selection of Intra-prediction is one of the important issues influencing H.264 coding rate.H.264/AVC is a variety of models from multiple directions of intra-prediction,the utilization rate distortion optimization algorithm,which selects the best mode,results in a high degree of algorithmic complexity.This paper analyzes intra-prediction mode of fast algorithms based on the current situation,proposes a new improved algorithm;by using the histogram which describes the distribution information of image gray as the foundation to judge the flat degree of images,puts forward the dual-threshold and the adjacent mode method;and in order to reduce the calculated quantities of RD_Cost,proposes double threshold again to determine the effectiveness of the most possible mode of current macro block.A number of experiments prove that the algorithm can improve the intra-coding efficiency under the situation of maintaining the image quality and encoding performance.
出处
《科技情报开发与经济》
2010年第13期104-107,共4页
Sci-Tech Information Development & Economy
关键词
帧内预测
快速算法
双阈值法
intra-prediction
fast algorithm
double-threshold method
