The main aim of this paper is to describe a method for locating a subimage of a stored image that approximately matches a given query image. This matching can support naive users in accessing an image database according to image contents rather symbolic attributes. The query image can be either composed using painting tools or cuts out of an actual scanned image. Our method is based on the extraction of features from the query image and from the stored images. The following three steps are involved: (1) an ISODATA algorithm is applied to segment (into region) both the query image and the stored images; (2) the normalized moment and geometrical features are computed from the segmented regions, and (3) a matching process is run on the resulting features to find those stored images which should be retrieved. The result is an ordered list of stored images or subimages from the database.
"Shape analysis for image retrieval", Proc. SPIE 2185, Storage and Retrieval for Image and Video Databases II, (1 April 1994); doi: 10.1117/12.171781; https://doi.org/10.1117/12.171781