Patent ID: 6741739
Filing Date: 2004-05-25
Classification: G06T

Abstract:
An imaging apparatus, comprising,means for sampling image information to provide an image signal, means for computing a wavelet transform of the image signal up to a predetermined level such that the transform is comprised primarily of high frequency components which are attributable to noise, wherein each wavelet transform includes a wavelet scaling matrix and a wavelet coefficient matrix, means for constructing altered wavelet coefficient matrices for each level up to the predetermined level, means for deriving a frequency thresholded signal by computing an inverse wavelet transform for each level below the predetermined level, down to the level below the first level, while using for the computation for each level the wavelet scaling matrix and the altered wavelet coefficient matrix corresponding to the level above, and means for subtracting the frequency thresholded signal from the image signal to provide an image signal having an improved signal to noise ration.