A Flexible Reference Picture Selection Method for Spatial DIRECT Mode in Multiview Video Coding

The motion information of the macroblock signaled as the spatial DIRECT mode can be derived from the neighboring blocks. The closest reference picture in the reference picture list used by the neighboring blocks is selected as the reference picture of the macroblock. Both temporal and interview reference pictures are put into the reference picture list in order to improve the coding efficiency in MVC. A flexible reference picture selection method taking the diversity of reference picture list into account is proposed in this paper. The experimental results show that the proposed method can improve coding efficiency especially when the interview reference pictures are put ahead of the temporal reference pictures.

1. Introduction

3D video has gained increasing research interests due to its wide variety of applications, including free-viewpoint television, 3D television and surveillance [1]. For a 3D system, multiple cameras are usually used to capture the same scene and the video data captured by each one of cameras is called a view. Since multiview video leads to an enormous amount of data, a crucial issue for its wide application is how to encode all views efficiently. Multiview Video Coding (MVC) is then put forward with a focus on improving the coding efficiency with regard to all views. A new standard for MVC is under development by the Joint Video Team (JNT) of ISO/IEC-MPEG and ITU-TVCEG [2], which will be an extension of H.264/AVC.