Wavelet Based Extraction of Blood Vessels

An algorithm for the segmentation of blood vessels based on the correlation of different wavelet scales is presented. First the wavelet coefficients are computed for a defined number of scales and then the correlation between the corresponding coefficients of two consecutive scales is computed. The normalized product is used as a reference threshold for retaining original wavelet coefficients. If the normalized product is greater than the corresponding original wavelet coefficient, the original coefficient is retained for image reconstruction by inverse wavelet transform, otherwise the coefficient is changed with zero value. Low frequency wavelet coefficients matrix is not used in image reconstruction process as we want only the edge information. The proposed algorithm is quite general and can be used for the extraction of any type of blood vessels and provides very promising results.