MPEG-4到AVS转码的关键技术研究

摘要

Transcoding techniques were used to achieve the smooth transition from the audio video coding standard MPEG-4 to the standard AVS to create the requirements for AVS equipments's access to the existing video resources. The fast cascaded pixel-domain transeoder (FCPDT) and its several transcoding strategies were proposed to effectively improve the operation efficiency during the transition process from MPEG-4 to AVS while ensuring a desired parameter conversion accuracy, and to sueceed in solving the difficult problem that a multifunctional and high-quality AVS transcoder should instantaneously operate. The experimental results indicate that the executing time of the proposed FCPDT is less than 10％of that of the cascaded transcoder based on RM5.2c, with the objective image-quality difference of about 0.5 - 1.5dB.The proposed method also has the referential value for other transcodings between the standards of the same kind.%采用转码技术实现了视频编码标准MPEG-4到AVS的平滑过渡,为AVS设备访问现有视频资源创造了条件.提出了快速级联型像素域转码器(FCPDT)结构及多项转码策略,在保证参数转换精度的前提下,有效提高了MPEG-4到AVS转码过程的运算效率,成功解决了多功能高质量AVS转码器实时实现的难题.实验结果表明,FCPDT的转码时间,不到基于RM5.2c的级联型转码器的10%,客观图像质量相差0.5～1.5dB.该方法对同类型其它标准间的转码亦有借鉴价值.