本文提出了一种基于脊向指纹滤波预处理方法。
In the paper, a new algorithm of fingerprint images based on the filtering of the ridge direction is introduced.
它包括二维匹配滤波预处理以增强血管的灰度，以及用灰度-梯度共生矩阵的最大熵阈值化方法。
Entropy thresholding method is an automatic technique for thresholding of digital images based on gray level-gradient co-occurrence matrix and the maximum entropy principle.
通过线特征滤波预处理和投影变换检测机场跑道线，进一步用模板匹配识别跑道端点以进行定位。
Through the linear feature enhancement and Randon transform to locate the runway line, then using model matching to find the exactly position of the runway end for registration of the airfield.
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