| 摘要 |
<p>An enhancement method of a fingerprint image is disclosed, which comprises the following steps: analyzing from the perspective of a frequency domain and removing the high-frequency component of an original fingerprint image by the fuzzy processing of the image; then, subtracting the fuzzed fingerprint image by utilizing the original image to remove the low-frequency component of the image so as to obtain relatively pure image high-frequency information with the low-frequency information of the image being already removed substantially; and afterwards, superposing the high-frequency information image with the original image to obtain the image, the high-frequency part thereof is enhanced, i.e. the sharpened image. Further, the influence of the nonuniformity of an illumination field is eliminated by utilizing the difference of the sharpened image and the sharpened image processed by fuzzification. Thus, the obtained enhanced fingerprint image is relatively ideal and it is convenient to select a threshold value in a subsequent image processing process when binarization processing is carried out on the fingerprint image, thereby lowering the probability of the erroneous extraction of the characteristic of a fingerprint and improving the accuracy of fingerprint identification.</p> |
