Deep Video Coding With Bit-Depth Scalability

Deep video coding techniques have achieved significant advancements, leading to enhanced compression performance. However, existing approaches are primarily optimized for 8-bit content, thereby limiting their effectiveness in scenarios with different bit-depths. In this paper, we propose a deep bit-depth scalable video codec (DB-SVC) that supports two-layer scalability for different bit-depths. First, we design a base layer (BL) for low bit-depth (LBD) videos, incorporating a dual-stage multi-scale feature extraction module (DFEM) to enhance compression efficiency while providing reference features for subsequent coding. Second, we introduce an inter-layer bit-depth enhancement module (IBEM) that refines the bit-depth of BL reconstructed frames by leveraging interlayer information, thus enhancing the reference quality without increasing coding overhead. Third, we design an enhancement layer (EL) tailored for high bit-depth (HBD) videos, employing a bit-depth residual compression (BRC) method to achieve a more accurate reconstruction of HBD videos. DB-SVC supports progressive decoding of LBD and HBD videos, accommodating diverse display requirements. Experimental results demonstrate that DB-SVC outperforms state-of-the-art codecs in LBD and HBD scenarios. At the same PSNR/MS-SSIM levels, DB-SVC achieves average bit-rate savings of 11.94%/53.35% for 8-bit videos and 55.98%/73.16% for 10-bit videos while comparing with VTM13.2, showcasing its superior compression performance.