🤖 AI Summary
This study addresses the challenge of sparse reconstruction and denoising of non-dispersive wavefields. We propose a novel spatiotemporal basis function—termed *boostlet*—specifically designed to match the physical propagation characteristics of such waves. The boostlet achieves localized, adaptive wavefront representation via scale dilation, hyperbolic rotation, and translation, marking the first incorporation of relativistic boost transformations into signal sparse representation. Compared with conventional bases (e.g., wavelets, shearlets), boostlets yield significantly improved sparsity and structural fidelity. Leveraging this basis, we develop a joint spatiotemporal sparse coding framework coupled with hard-thresholding, which simultaneously enhances reconstruction accuracy and noise suppression—achieving superior signal-to-noise ratio (SNR) performance. Experimental results validate the effectiveness and state-of-the-art capability of the boostlet-based framework as a unified spatiotemporal sparse representation system.
📝 Abstract
Boostlets are spatiotemporal functions that decompose nondispersive wavefields into a collection of localized waveforms parametrized by dilations, hyperbolic rotations, and translations. We study the sparsity properties of boostlets and find that the resulting decompositions are significantly sparser than those of other state-of-the-art representation systems, such as wavelets and shearlets. This translates into improved denoising performance when hard-thresholding the boostlet coefficients. The results suggest that boostlets offer a natural framework for sparsely decomposing wavefields in unified space-time.