Patent ID: 6393157
Filing Date: 2002-05-21
Classification: G06T

Abstract:
A method for automatically detecting objects within an original image, said objects having a size which is smaller than a predefined maximum size comprising the steps of:acquiring a digital signal representation of said original image, applying said digital signal representation to a computer to subject it to a process which results in a new image which contains only reconstructions of said objects, said process comprising the steps of: (i) generating Fourier components of said original image by applying the Fourier transform; (ii) defining a critical Fourier wavelength equal to the maximum size; and (iii) applying one of the techniques of entropy maximisation and cross-entropy minimisation to said original image to create said new image wherein (a) the amplitudes and the phases of the Fourier components of said new image with wavelengths that are shorter than said critical Fourier wavelength are substantially the same as the amplitudes and the phases of the Fourier components of said original image, and wherein (b) for the amplitudes and the phases of Fourier components having wavelengths that are longer than said critical wavelength, new values are estimated so that either image cross-entropy is minimised or image entropy is maximised.