任意帧结构MPEG-2到MPEG-4 FGS视频流转换编码算法

A Transcoding Algorithm for MPEG-2 to MPEG-4 FGS with Arbitrary Frame Structures

在从MPEG-2视频流到MPEG-4 FGS视频流的转换编码中,需要考虑多种帧结构类型。本文就三种帧结构:全I帧,IPPP,IBBP进行了分析,并选出对应的转换编码结构。其中兼顾了效率和输出质量。在IPPP帧结构中,转换编码结构需要对显著的色差漂移误差进行校正。对于IBBP帧结构,因色差漂移误差不明显,故选择较简单的编码端闭环结构转换编码器。

For transcoding from MPEG-2 stream to MPEG-4 FGS streams, some kinds of frame structures must be taken into account. In this paper, three frame structures such as all-Ⅰ, IPPP and IBBP are considered in choosing proper transcoding architectures for them. In the case of IPPP frame structure, the obvious chroma drift errors had been corrected in our transcoding architecture. For IBBP case, the encoding closed loop transcoder is suggested.