24. A system for content based image retrieval, the system including: a signature processor of at least one processing device adapted to generate a signature based at least in part on a curvelet transform, the signature including a portion of a plurality of curvelet coefficients of the curvelet transform that is significant, wherein the signature is a vector of real numbers with a length less than a number of corresponding image pixels; a database including a plurality of database images, wherein each database image is associated with a database image signature generated by the signature processor; and a matching processor of the at least one processing device adapted to determine a query signature for a query image using the signature processor, and wherein the matching processor is adapted to determine at least one matching image from the plurality of database images based at least in part on the query signature and the associated database image signatures.
24. A system for content based image retrieval, the system including: a signature processor of at least one processing device adapted to generate a signature based at least in part on a curvelet transform, the signature including a portion of a plurality of curvelet coefficients of the curvelet transform that is significant, wherein the signature is a vector of real numbers with a length less than a number of corresponding image pixels; a database including a plurality of database images, wherein each database image is associated with a database image signature generated by the signature processor; and a matching processor of the at least one processing device adapted to determine a query signature for a query image using the signature processor, and wherein the matching processor is adapted to determine at least one matching image from the plurality of database images based at least in part on the query signature and the associated database image signatures. 29. The system of claim 24 , wherein the curvelet transform is: { I ⁡ ( x 1 , x 2 ) } ⁢ ⇒ FDCT ⁢ I low + { c j , l , k = 〈 I , φ j , l , k 〉 } j ≥ 1 where FDCT is a Fast Discrete Curvelet Transform (FDCT), I represents an input digital image, I low represents a low resolution image, c represents a curvelet coefficient, φ represents a curvelet function, j represents a scale, l represents an orientation, and k represents a location.