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Speckle correction in ultrasound b-mode images: a zeros-based approach

The specific problem of compensating for the presence of speckle in ultrasound B-mode imaging systems is addressed. The basic principles underlying current approaches to speckle reduction are first briefly reviewed. For real-time imaging systems, speckle reduction techniques which operate in the context of a single image (or `look') of the object are of more practical importance. A large number of such techniques have been developed which are based on some form of noise model of speckle, and are hence statistical in nature. All such approaches reduce the presence of speckle at the cost of some other factor of image quality, usually resolution. This paper examines an alternative approach to the single image problem, based on an alternative speckle definition, which does not suffer the usual resolution trade-off. The basis of the approach is to reformulate the single image problem in terms of a structure uniqueness problem which underpins a speckle model based on zeros of the analytic continuation of the rf A-line signal into the complex time and frequency planes.