By implementing a mosaic multispectral technology, Safran designed a compact and lightweight camera able to create a snapshot multispectral image of eight spectral bands and a panchromatic one. The camera is a silicon sensor sensitive both on the Visible and on the Near-Infrared wavebands, on which a spectral filters matrix is placed. The spectral bands where carefully chosen based on a large database of hyperspectral images of camouflage targets in realistic backgrounds. The multispectral images acquired with this camera are numerically treated and projected in an adapted space to maximize the visual contrast between each point and its surrounding. Then, a metric determines if the pointed area corresponds to a spectral anomaly, and potentially a camouflaged target. Using this snapshot ability; Safran designed a real-time camouflage detection device integrated in an armored vehicle sight system with the aim of demonstrating the benefit of a multispectral sensor on conventional imagers, such as daylight or thermal cameras. With this device, we conducted several test campaigns. During these campaigns, several types of relevant targets were evaluated, such as armored personnel carriers with or without camouflage nets, infantrymen and soldiers in camouflage Ghillie suits. For each multispectral acquisition, we also acquired images with conventional cameras to be clearly able to appreciate the gain provided by the multispectral channel and evaluate the operational interest of this technology.
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