摘要
针对无线网络中移动设备低码率、低分辨率的视频流要求,提出一种MPEG-2到H.264降空间分辨率转码的快速编码模式选择算法。在视频序列2∶1下采样后,利用MPEG-2解码端运动矢量的距离和方向信息决定是否将相邻8×8块合并成8×16、16×8、16×16块,若不能合并,则用解码端AC系数的组合判断是否将8×8块继续分割为8×4、4×8、4×4块,既考虑到H.264编码中的所有块大小,又避免了传统率失真选择算法的庞大计算量。实验结果显示,该方法在保证相当的视频质量情况下,平均节约87.02%的编码模式选择时间。
Aimed at the low rate and low resolution video streaming demands of mobile devices in wireless network, this paper presented a fast coding mode decision algorithm from MPEG-2 to H.264 downscaling transcoding. After video 2∶1 downsca-ling, applied the distance and direction of motion vector in MPEG-2 to decide whether the neighboring 8×8 blocks to be combined into blocks with larger sizes, such as 8×16, 16×8 or 16×16, if not, then splited the 8×8 block into 8×4, 4×8 or 4×4 block according to the combination of AC coefficient in MPEG-2. Considered all of the block sizes in H.264 and avoided the high complexity of the traditional RDO algorithm in the process of transcoding. Experimental results demonstrate that it can save 87.02% of average coding mode decision time with negligible degradation in video quality.
出处
《计算机应用研究》
CSCD
北大核心
2010年第5期1991-1993,共3页
Application Research of Computers
基金
广西科学研究与技术开发计划资助项目(05112001-7A2)
