The first method adopts dynamic threshold to detect the threads of finger-print, and gives the bilevelimage directly.
第一种方法采用动态门限检测指纹的隆线，直接给出二值化象图。
2
In order to deblur the image, deconvolution and waveform recovery are necessary. Deconvolution is an ill-posed problem. Bar code is a kind of bilevel waveform.