Patent Document ID: 8571325
Application ID: 13077042
Patent Status: 1

Claim One:
1. A method of determining the presence of a target substance, the method comprising: receiving a hyperspectral image comprising spectra of a plurality of scene pixels indicative of light and other radiation absorbed by, or emitted from, a target substance; determining, for each scene pixel, a measure of spectral match between a respective spectrum of the scene pixel and a reference spectrum of the target substance; determining, for each scene pixel, a measure of spectral mismatch between a respective spectrum of the scene pixel and the reference spectrum of the target substance; and detecting a presence of the target substance within the hyperspectral image in response to the determined measures of spectral match and spectral mismatch, wherein determining the measure of spectral match comprises applying a matched filter to the spectrum of the scene pixel or a filter adapted to measure angular deviation between the spectrum of the scene pixel and the reference spectrum of the target substance.