Hartley transform in compression of medical ultrasonic images

In this paper the Hartley transform has been used for both compression and filtering of medical ultrasonic images. The Hartley transform shares some features of the Fourier transform and, most importantly, there exists a computationally effective butterfly algorithm of the transform. Compression relies on filtering out higher harmonics of the forward Hartley transform and saving the result rather as the image than the coefficients of the transform. In this case the images´ size is reduced 16 times without significant loss of valuable medical information.