🤖 AI Summary
To address low-fidelity reconstructions in compressive sensing (CS) for images—caused by measurement incoherence and the absence of explicit measurement representation during reconstruction—this paper proposes MEUNet, a physics-guided deep unfolding network. Methodologically: (i) we design an asymmetric Kronecker CS model to enhance measurement incoherence; (ii) we introduce a measurement-aware cross-attention mechanism within an explicit gradient-descent framework to learn robust implicit representations. By integrating Kronecker tensor products, deep unfolding architecture, and attention-based modeling, MEUNet achieves measurement-enhanced reconstruction. Extensive experiments on multiple benchmark datasets demonstrate that MEUNet achieves state-of-the-art reconstruction accuracy (PSNR/SSIM) with significantly fewer parameters and faster inference speed than leading CS methods.
📝 Abstract
Deep networks have achieved remarkable success in image compressed sensing (CS) task, namely reconstructing a high-fidelity image from its compressed measurement. However, existing works are deficient inincoherent compressed measurement at sensing phase and implicit measurement representations at reconstruction phase, limiting the overall performance. In this work, we answer two questions: 1) how to improve the measurement incoherence for decreasing the ill-posedness; 2) how to learn informative representations from measurements. To this end, we propose a novel asymmetric Kronecker CS (AKCS) model and theoretically present its better incoherence than previous Kronecker CS with minimal complexity increase. Moreover, we reveal that the unfolding networks' superiority over non-unfolding ones result from sufficient gradient descents, called explicit measurement representations. We propose a measurement-aware cross attention (MACA) mechanism to learn implicit measurement representations. We integrate AKCS and MACA into widely-used unfolding architecture to get a measurement-enhanced unfolding network (MEUNet). Extensive experiences demonstrate that our MEUNet achieves state-of-the-art performance in reconstruction accuracy and inference speed.