Intelligent low rate compression of speckled SAR imagery

This paper describes a compression technique under development at Sandia National Laboratories for the compression of complex synthetic aperture radar (SAR) imagery at very low overall bit rates. The methods involved combine several elements of existing and new lossy and lossless compression schemes in order to achieve an overall compression ratio of large SAR scenes of at least 50:1, while maintaining reasonable image quality. It is assumed that the end user will be primarily interested in specific regions of interest within the image (called "chips"), but that the context in which these chips appear within the entire scene is also of importance to an image analyst. The term "intelligent" is used to signify an external cuer which locates the chips of interest.