Pistol image retrieval by shape representation

Databases have been used to record data in forensic science, such as fingerprints, shoeprints, and photos. In traditional databases, we use text as the keyword for retrieving data (text-keyword retrieval); however, in some applications, text is not proper to describe the searching target, and in this case, image plays an important role. In this paper, we use image features as the keywords, and show its potential for building up a prototype of pistol image databases. In current firearm databases of forensic science, the retrieval method is still by text-keyword retrieval. For experienced forensic examiners, this kind of databases may satisfy their requirement. However, for people who have little gun knowledge, how can they find the possible gun candidates or similar guns in the databases, if there are not any available words or marks on the gun? In this paper, we try to retrieve similar pistol images by the pistol shape instead of text-keyword. This method can narrow down the searching range while identifying pistols by firearm databases. There are more than 300 pistol images in our pistol image database. From the experimental results, we can retrieve the similar pistol images in top five candidates for each pistol image. (c) 2004 Elsevier Ireland Ltd. All rights reserved.