In the pretreatment , we mend image by gray - level and direction - raph filtering . the program we proposed , without binarization and thinning , has high rapidity and saves a lot of calculation time 预处理时,先对采集的指纹进行灰度滤波,然后再通过计算块方向图对指纹进行方向图滤波,从而实现灰度修补。
This paper completely pay respect to the two characters in the ridge ' s binarization step . and in this paper , we using the information of the pixel ' s grads which in the fingerprint ' s digital image and propose an approach that we can confirm the block ' s orientation 本文在脊线二值化过程中充分考虑了这两个特性,并且利用指纹图像中点梯度的方向信息,提出了用相位编组法确定块方向,然后基于块方向进行方向滤波,收到了较好的效果。
A new full fingerprint preprocessing algorithm , which improves traditional fingerprint images segment algorithm by using residual block disposal and smoothing , was introduced , and an orientation - match method that filters orientation field to enhance image . . 介绍并实现了一套完整的指纹图像预处理方法,通过剩余块处理和平滑方法改进了传统的指纹图像分割算法使用方向匹配的方法对指纹图像方向块进行方向滤波完成图像增强并除去细化后存在的短线和毛刺。
Then the gray image is transformed into a binary image through a one - by - one - point section - threshold binary algorithm . after that , a postprocessing is implemented on the given binary image . in the part of thinning algorithm , an improved thinning algorithm derived from the opta is introduced in , for the purpose of producing high quality skeleton of fingerprints , on which the more accurate fingerprint feature location and type are based 采用离散方向法来求取指纹的点方向图,进而用直方图法结合动态分块得到指纹的块方向图;再对指纹图像进行方向法滤波;然后使用逐点局部阈值法,对指纹图像进行二值化处理;二值化后对二值图进行后处理;细化算法采用基于opta的改进细化算法,可以获得高质量的指纹骨架。
进行: be in progress; be underway; ...方向: direction; orientation船航行方向: tack飞行方向: direction of flight; flight direction滑行方向: line of travel; taxi direction可行方向: feasible direction平行方向法: parallel method orientation上行方向: udirection下行方向: down direction运行方向标: traffic direction sign字符行方向: line writing direction走行方向: direction of travel遵行方向: this way船舶航行方向: direction of ship travel磁带运行方向: tape running direction道路通行方向: driving on the left or right; traffic directionality改变运行方向: traffic reversal禁行方向标志: do not enter sign列车运行方向: current of traffic实际飞行方向: actual flight direction使用平行方向: use parallel direction瞬时飞行方向: instantaneous flight direction一致可行方向: uniformly feasible direction运行方向电路: traffic direction circuit反平行方向样模: antiparallel copying