Abstract: Systems and methods to detect a scratch are provided. The method includes identifying, via an OPTICS technique, a cluster of points on an image. The method also includes utilizing a principal curves technique to identify a curve that approximates one or more points of the cluster of points as a smooth curve. The method further includes determining one or more characteristics of the curve. The method further includes determining one or more characteristics of the cluster. The method further includes identifying a scratch based on at least one of the one or more characteristics of the curve and the one or more characteristics of the cluster.