Modified curvelet transform with vocabulary tree for content based image retrieval

This work represents a modified curvelet transform (MCT) and its combination with vocabulary tree (VT) for feature collection and retrieval of the images from database. MCT has been implemented using the Gabor wavelet sub-bands. The proposed algorithm captures edge information in an image more accurately than Gabor transform (GT) and curvelet transform which uses à trous wavelet transform (ACT) for decomposition of an image. The MCT uses the ridgelet transform as a component step and implements curvelet sub-bands using a filter bank of Gabor wavelet filters. Descriptor vectors (energy histogram vectors) of each image are indexed using vocabulary tree. The proposed method is tested on Corel image database and the retrieval results demonstrate significant improvement in weighted average precision, average precision, average retrieval rate, and average rank compared to the ACT and GT.