Dual-View Hyperspectral Anomaly Detection via Spatial Consistency and Spectral Unmixing

Abstract

Anomaly detection is a crucial task for hyperspectral image processing. Most popular methods detect anomalies at the pixel level, while a few algorithms for anomaly detection only utilize subpixel level unmixing technology to extract features without fundamentally analyzing the anomalies. To better detect and separate the anomalies from the background, this paper proposes a dual-view hyperspectral anomaly detection method by taking account of the anomaly analysis at both levels mentioned. At the pixel level, the spectral angular distance is adopted to calculate the similarities between the central pixel and its neighbors in order to further mine the spatial consistency for anomaly detection. On the other hand, from the aspect of the subpixel level analysis, it is considered that the difference between the anomaly and the background usually arises from dissimilar endmembers, where the unmixing will be fully implemented. Finally, the detection results of both views are fused to obtain the anomalies. Overall, the proposed algorithm not only interprets and analyzes the anomalies from dual levels, but also fully employs the unmixing for anomaly detection. Additionally, the performance of multiple data sets also confirmed the effectiveness of the proposed algorithm.

Mapping NYF pegmatite outcrops through high-resolution Worldview-3 imagery

“…In a subpixel occurrence situation, the pixel is much bigger than the target we want to identify. Consequently, the spectrum from that pixels will be mixed, containing information from all the elements present in the pixel [2][3][4] . In summary, mixed spectra can make the target classification difficult.…”