The advent of compression standards

such as JPEG and MPEG

has led to the popularity of the compressed form of image data

and that has brought on the proliferation of image retrieval techniques in the compressed domain. In this paper

we make a comprehensive review and discussions on the compressed domain retrieval techniques proposed in the literature

including the lastest achievements in this field. First

we give the general concepts of the image retrieval technology. Secondly

we analyze different retrieval techniques

including transform domain techniques using Fourier transform

discrete cosine transform

subbands and wavelets

and spatial domain techniques using vector quantization and fractals. Thirdly

we discuss and compare these image retrieval techniques and draw some useful conclusions. In addition

an example application of image retrieval in the compressed domain is presented. Finally

we make a discussion on some open problems and point out possible directions for further research.