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.