Fast and quality-efficient scheme for asymmetric multi-view video plus depth coding under the bitrate constraint

• Asymmetric multi-view video plus depth based 3D video coding framework.
• Our proposed coding scheme is specially designed for bitrate-constrained situations.
• Our proposed coding scheme can significantly reduce the encoding time.
• The quality of the reconstructed depth video and the virtual view can be improved.

Recently, multi-view video plus depth based 3D video (3D-MVD) coding has been studied extensively. This paper presents a fast and efficient asymmetric 3D-MVD coding scheme under specified bitrate constraints. To efficiently encode depth images, a texture image-assisted inter prediction strategy is proposed to determine whether to use a direct copy of the co-located block as the inter prediction so as to skip the normal encoding process. In addition, an adaptive weighted mode in-loop filter strategy is proposed to refine the reconstructed depth image quality. Both strategies help to significantly reduce the encoding time and improve the reconstructed depth image quality under the bitrate constraint. Experiment results showed that the proposed asymmetric 3D-MVD coding scheme does achieve better quality of the reconstructed depth videos and the rendered virtual views at a less encoding-time requirement when compared with the state-of-the-art scheme by Shao et al. and the traditional 5:1 bitrate allocation scheme.