基于动态范围调整的指纹图像增强方法

采用基于动态范围调整的方法，并适当地把图像最亮和最暗附近很少量灰度级像素点滤除，对图像灰度进行线性展宽，实现图像灰度动态范围的自动调整，提高图像的对比度。实验结果表明，该方法可有效地滤除在灰度边界值附近的灰度干扰，图像的质量和对比度明显提高，图像的亮区和暗区的细节都有明显增强，而且处理速度快，鲁棒性好。

Fingerprint image enhancement method based on dynamic range adjustment

Based on the dynamic range adjustment method, a small amount of grayscale pixels on the image near the brightest and darkest areas are filtered, and the image grayscale range is linear broadened so as to realize automatic adjustment of image gray dynamic range, and improve the image contrast. The experimental results show that this method can effectively filter gray interference near gray boundary value, the quality and contrast of the images is obviously improved, and details of the image of the light area and the dark area have enhanced obviously, with high processing speed and good robustness.