HANeRV: Hierarchically Adaptive Neural Representation for Video Compression

Recent advances in video compression introduce implicit neural representation (INR) based methods, which effectively capture global dependencies and characteristics of entire video sequences. Unlike traditional and deep learning based approaches, INR-based methods optimize network parameters from a global perspective, resulting in superior compression potential. However, most current INR methods utilize a fixed and uniform network architecture across all frames, limiting their adaptability to dynamic variations within and between video sequences. This often leads to suboptimal compression outcomes as these methods struggle to capture the distinct nuances and transitions in video content. To overcome these challenges, we propose Hierarchically Adaptive Neural Representation for Video Compression (HANeRV), an innovative INR-based video compression network that adaptively conducts structure optimisation based on the specific content of each video sequence. To better capture dynamic information across video sequences, we propose a dynamic architecture-level adjustment (DAA). Furthermore, to enhance the capture of dynamics between frames within a sequence, we implement a dynamic frame-level adjustment (DFA). Finally, to effectively capture spatial structural information within video frames, thereby enhancing the detail restoration capabilities of HANeRV, we devise a structure level hierarchical structural adaptation (HSA). Experimental results show that HANeRV achieves state-of-the-art performance among INR-based video compression methods and surpasses the H.266/VVC (x266, medium preset) anchor on diverse datasets.