**2.2 Classification**

Efficient texture representation is important for content based retrieval of image data(Lopez &Cumplido 2004). The idea is to compute a small set of texture-describing features for each image in a database in order to allow a search of the database for images containing a certain texture. The DT-CWT has been found to be useful for classification by number of authors.Each uses the DT-CWT in different ways to compute texture features for an entire image:

