| 摘要 |
FIELD: physics; image processing. ^ SUBSTANCE: invention relates to processing images of papillary lines and can be used in law-enforcement bodies and systems for limiting access with personal identification. The method involves standardisation of the beginning of an image, calculation of brightness gradients, determination of directions of papillary lines from the brightness gradients, breaking up the image into units, calculation of the fast Fourier transform for each unit, determination of periods of papillary lines for each unit, application of Gabor filters with parametres determined from the calculated periods and directions. The technical outcome is achieved due to that, to determined periods of papillary lines of a unit, a set of brightness lines of defined length is formed, with the centre in the middle of the unit in at least four directions. For the selected directions, coefficients of a one-dimensional fast Fourier transform are calculated, as well as the period of lines corresponding to the maximum of the spectral density. The least of the calculated periods is taken as the period of the unit. ^ EFFECT: increased reliability of determining periods of image units, from which Gabor filter parametres are determined, and cutting on image processing time. ^ 2 cl, 2 dwg |
