Image Feature Extraction Techniques and Their Applications for CBIR and Biometrics Systems

In CBIR (Content-Based Image Retrieval), visual features such as shape, color and texture are extracted to characterize images. Each of the features is represented using one or more feature descriptors. During the retrieval, features and descriptors of the query are compared to those of the images in the database in order to rank each indexed image according to its distance to the query. In biometrics systems images used as patterns (e.g. fingerprint, iris, hand etc.) are also represented by feature vectors. The candidates patterns are then retrieved from database by comparing the distance of their feature vectors. The feature extraction methods for this applications are discussed. Keywords—CBIR, Biometrics, Feature extraction