一种基于帧间和帧内宏块级的X264并行编码算法

摘要

结合H.264编码标准对X264编码器进行了分析与研究,目的在于提高编码速度,增强X264的实时性.在重点分析了宏块间数据依赖关系的情况下,针对帧间宏块级多线程并行编码的特点,本文提出了一种基于帧间和帧内宏块级的多线程并行编码算法.该算法在原有的帧间宏块级多线程并行编码的基础上,遵循宏块之间的空间相关性,为Ⅰ帧内每行宏块创建单独的线程,实现了帧间和帧内宏块级并行编码,达到了多粒度并行的效果.实验结果表明,该算法在视频序列能够有效地编码和保持峰值信噪比变化不大的情况下,提高了编码的加速比,从而加强了视频编码的实时性.%This paper studies the X264 encoder on the basis of a thorough knowledge about the H. 264 standard, aiming to accelerate the encoding speed and enhance the encoder's real-time ability. In the context of the data dependencies of the related macroblocks which are mainly analyzed, considering the characteristics of the parallel coding algorithm based on the macroblock-level of Inter-Frame, the paper proposes a new multi-thread parallel coding algorithm. On the basis of the original multi-thread parallel algorithm of the inter-frame macroblock-level and the following spatial correlation conditions,the algorithm which creates a thread for each row in the I frame,implements the parallel encoding of the inter-frame and intra-frame macroblock-level and achieves the effect of multi-granularity parallelism. The experimental results illustrate that the propsed algorithm improves the encoding speedup while the video sequences are effectively encoded and with the PSNR holds basically unchanged. ,and the real-time encoding is enhanced.