A Flexible Algorithm Design of Spatial Scalability for Real-time Surveillance Applications

The Surveillance Video and Audio Coding )SVAC( working group is currently developing the third-generation video compression standard, SVAC 3.0. To extend this standard, this paper proposes a spatial scalable coding Scalable Surveillance Video Coding )SSVC( framework, so that the SVAC3.0 video stream can gracefully adapt to different transmission bandwidth limitations and the requirements of decoding hardware, while keep the quality of the reconstructed image without degradation. In order to achieve the scalability of hardware implementation, SSVC designs a flexible reference frame marking and usage scheme, so that the enhanced layer coding does not directly depend on the basic layer, and effectively reduces the coding coupling between layers. SSVC improves the motion vector prediction method, effectively utilizes the encoding information of the base layer, and is mainly compatible with SVAC3.0 syntax structures. In addition, SSVC provides several different operational modes to adapt to various application scenarios and achieve an optimal trade-off between coding efficiency and complexity. The performance comparisons among simulcast stream and SSVC, single-layer stream and SSVC enhancement layer, as well as experimental data for different operational modes are provided. The coding efficiency and computational complexity are also analyzed.