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arXiv · 2403.18535

Theoretical Bound-Guided Hierarchical VAE for Neural Image Codecs

Yichi Zhang·Zhihao Duan·Yuning Huang·Fengqing Zhu
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Abstract

Recent studies reveal a significant theoretical link between variational autoencoders (VAEs) and rate-distortion theory, notably in utilizing VAEs to estimate the theoretical upper bound of the information rate-distortion function of images. Such estimated theoretical bounds substantially exceed the performance of existing neural image codecs (NICs). To narrow this gap, we propose a theoretical bound-guided hierarchical VAE (BG-VAE) for NIC. The proposed BG-VAE leverages the theoretical bound to guide the NIC model towards enhanced performance. We implement the BG-VAE using Hierarchical VAEs and demonstrate its effectiveness through extensive experiments. Along with advanced neural network blocks, we provide a versatile, variable-rate NIC that outperforms existing methods when considering both rate-distortion performance and computational complexity. The code is available at BG-VAE.

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Yichi Zhang, Zhihao Duan, Yuning Huang, Fengqing Zhu. 2024-03-27. Theoretical Bound-Guided Hierarchical VAE for Neural Image Codecs. https://arxiv.org/abs/2403.18535

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