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"RedLight is the fastest law enforcement pornography scanner available. RedLight detects pornography based on how law enforcement investigates a case - by finding likely pornography in images (and soon in video) very quickly, allowing visual confirmation by the investigator through a display of thumbnails, and then exporting selected videos, images, reports, and hash sets (suitable for importing into powerful analysis tools such as EnCase, FTK, and X-Ways). It uses sophisticated image analysis techniques to detect pornography through characteristics such as high concentrations of skin tone, and edges indicative of humans. RedLight achieves very good accuracy while being by far the fastest detection tool of its kind - finding images quickly and showing them in real-time as it finds them." dfcsc.uri.edu/research/redLight