Matching Facial Composite Sketches to Police Mug-Shot Images Based on Geometric Features

Abstract

Composite sketches are frequently used to help track down suspects in a crime in which there is no photographic evidence. Automatic retrieval of photos of suspects from police mug-shot databases can help police narrow down potential suspects quickly. This paper describes a novel approach for matching facial composite sketches to police mug-shot images. Proposed method is based on Geometric Features. To recognize a facial composite we focussed on face geometric features like eyes, eyebrows, nose, lips, and face cutting along with their length and width ratios. This system has five components 1) Extract components from a face image/composite sketch 2) Compute Ratios of Length, Width and Area 3) Represent each image component as a vector 4) Mean of the vectors are computed and subtracted from each component vector to get a set of vectors called zero-mean vectors 5) Searching for mug shot images in the database based on a query sketch drawn by an artist. It has useful applications for both law enforcement and digital entertainment. We assume that mug shot images to be studied are in frontal pose, under normal lighting with neutral expression, and have no occlusion. Extensive experiment has been conducted with 50 male and female face/sketch database from CUHK face database.