1. A method for selecting a subset of hyperspectral imaging wavebands to detect a target in a scene, the method comprising: in a filtering engine provided with a plurality of spectra of a target and a covariance matrix of a scene, for each spectrum in the plurality of spectra of the target: computing a signal-to-clutter ratio of a full set of wavebands representing the probability of detecting the target viewed in the scene; selecting a subset of wavebands from the full set of wavebands; computing a signal-to-clutter ratio of the selected subset of wavebands representing the probability of detecting the target viewed in the scene using the selected subset of wavebands; comparing the signal-to-clutter ratio of the subset of wavebands to the signal-to-clutter ratio of the full set of wavebands; determining whether the subset of wavebands is a good enough set of wavebands based on the comparison; and providing the good enough set of wavebands to detect the target in the scene.