旋转参数化图分数阶傅里叶变换:定义、性质和最优滤波
Rotation-Parameterized Graph Fractional Fourier Transform: Definition, Properties, and Optimal Filtering
AI总结:
本文提出旋转参数化图分数阶傅里叶变换(RP-GFRFT),通过统一分数阶和旋转参数化的谱分析,解决现有方法在旋转基控制和零角度退化方面的不足,提升图信号处理的去噪、重建和特征保留性能。
摘要:
图谱表示在图信号处理中是基础,为分析图结构数据提供严谨的框架。图分数阶傅里叶变换(GFRFT)通过分数阶参数扩展图傅里叶变换(GFT),实现灵活的谱分析并保持数学一致性。角图傅里叶变换(AGFT)通过旋转GFT特征向量引入角度控制;然而现有构造可能无法在零角度时精确还原为GFT,削弱理论一致性和可解释性。为解决这些互补的局限性,即GFRFT缺乏基于旋转的基控制和AGFT的零角度退化问题,本文提出旋转参数化图分数阶傅里叶变换(RP-GFRFT),统一分数阶和旋转参数化的谱分析。构造了一个保持退化的旋转矩阵族以保证在零角度时精确还原为GFT。然后提出了两种RP-GFRFT变体,I-RP-GFRFT和II-RP-GFRFT,并通过理论分析确认其幺正性、可逆性、还原行为和光滑参数依赖性。将分数阶和旋转角度联合优化用于自适应图谱滤波。在真实世界信号、图像和点云上的实验表明,RP-GFRFT在去噪精度、重建质量和特征保留方面优于GFRFT、AGFT和代表性滤波基线。
英文摘要:
Graph spectral representations are fundamental in graph signal processing, providing a rigorous frameworkforanalyzing graph-structured data. The graph fractional Fourier transform (GFRFT) extends the graph Fourier transform (GFT) through a fractional-order parameter, enabling flexible spectral analysis with mathematical consistency. The angular graph Fourier transform (AGFT) further introduces angular control by rotating GFT eigenvectors; however, existing constructions may fail to reduce exactly to the GFT at zero angle, weakening theoretical consistency and interpretability. To address these complementary limitations, namely the lack of rotation-based basis control in GFRFT and the defective zero-angle degeneracy of AGFT, this paper proposes the rotation-parameterized graph fractional Fourier transform (RP-GFRFT), which unifies fractional order and rotation-parameterized spectral analysis. A degeneracy preserving rotation matrix family is constructed to guarantee exact GFT reduction at zero angle. TwoRP-GFRFTvariants,I-RP-GFRFTandII-RP-GFRFT,arethenformulated, with theoretical analyses confirming their unitarity, invertibility, reduction behavior, and smooth parameter dependence. The fractional order and rotation angle are jointly optimized for adaptive graph spectral filtering. Experiments on real-world signals, images, and point clouds demonstrate that RP-GFRFT improves denoising accuracy, reconstruction quality, and feature preservation over GFRFT, AGFT, and representative filtering baselines.
机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。