Neural Image Compression Using Masked Sparse Visual Representation
Wei Jiang, Wei Wang, Yue Chen
TL;DR
This paper tackles neural image compression via Sparse Visual Representation (SVR) by enabling robust, cross-platform transmission of integer codeword indices and addressing the rate–distortion tradeoff. It introduces Masked Adaptive Codebook learning (M-AdaCode), which masks latent-space weights to reduce transmitted data while a decoder-weight refiller reconstructs a rich latent feature using adaptive, semantic-class-dependent codebooks. The method achieves better rate–distortion tradeoffs across a wide range of bitrates on the JPEG-AI dataset, with notable improvements in SSIM and perceptual quality (LPIPS), while controlling bitrate through the masking rate defined by the number of kept codebooks per super-pixel. This work advances practical SVR-based neural image compression by balancing reconstruction fidelity and transmission costs, offering robust performance across heterogeneous hardware platforms and content types.
Abstract
We study neural image compression based on the Sparse Visual Representation (SVR), where images are embedded into a discrete latent space spanned by learned visual codebooks. By sharing codebooks with the decoder, the encoder transfers integer codeword indices that are efficient and cross-platform robust, and the decoder retrieves the embedded latent feature using the indices for reconstruction. Previous SVR-based compression lacks effective mechanism for rate-distortion tradeoffs, where one can only pursue either high reconstruction quality or low transmission bitrate. We propose a Masked Adaptive Codebook learning (M-AdaCode) method that applies masks to the latent feature subspace to balance bitrate and reconstruction quality. A set of semantic-class-dependent basis codebooks are learned, which are weighted combined to generate a rich latent feature for high-quality reconstruction. The combining weights are adaptively derived from each input image, providing fidelity information with additional transmission costs. By masking out unimportant weights in the encoder and recovering them in the decoder, we can trade off reconstruction quality for transmission bits, and the masking rate controls the balance between bitrate and distortion. Experiments over the standard JPEG-AI dataset demonstrate the effectiveness of our M-AdaCode approach.
