Knowledge-guided Complex Diffusion Model for PolSAR Image Classification in Contourlet Domain

TL;DR

This paper introduces a novel knowledge-guided complex diffusion model that leverages the Contourlet transform for improved PolSAR image classification, effectively capturing complex phase information and preserving structural details.

Contribution

It proposes a new diffusion model that integrates structural knowledge and multiscale features in the Contourlet domain for enhanced PolSAR classification.

Findings

Outperforms state-of-the-art methods on real-world datasets

Better preservation of edge details and region homogeneity

Effective modeling of complex-valued phase information

Abstract

Diffusion models have demonstrated exceptional performance across various domains due to their ability to model and generate complicated data distributions. However, when applied to PolSAR data, traditional real-valued diffusion models face challenges in capturing complex-valued phase information.Moreover, these models often struggle to preserve fine structural details. To address these limitations, we leverage the Contourlet transform, which provides rich multiscale and multidirectional representations well-suited for PolSAR imagery. We propose a structural knowledge-guided complex diffusion model for PolSAR image classification in the Contourlet domain. Specifically, the complex Contourlet transform is first applied to decompose the data into low- and high-frequency subbands, enabling the extraction of statistical and boundary features. A knowledge-guided complex diffusion network is then designed to model the statistical properties of the low-frequency components. During the process, structural information from high-frequency coefficients is utilized to guide the diffusion process, improving edge preservation. Furthermore, multiscale and multidirectional high-frequency features are jointly learned to further boost classification accuracy. Experimental results on three real-world PolSAR datasets demonstrate that our approach surpasses state-of-the-art methods, particularly in preserving edge details and maintaining region homogeneity in complex terrain.