一种新的指纹图像分割方法

在研究和分析方差法和方向法的基础上，提出了一种指纹图像分割的新方法。对每个指纹图像块，先分别沿平行于块方向和垂直于块方向求取灰度变化，然后针对整幅图像进行归一化处理，以这两个方向上的灰度变化作为判断依据，确定该块是属于前景区域还是背景区域。本算法充分利用了指纹图像特有的方向性和灰度特性，能准确地将背景区域从指纹图像中分离出来，从而取得了良好的分割效果。

New Method for Segmenting Fingerprint Image

The two common means for segmenting the fingerprint image are variance method and direction method, which utilize its gray characteristic and direction information, respectively. After investigating and analyzing the two methods, this paper presents a new approach to segmenting the fingerprint image. For each block of the image, two kinds of gray variations are calculated, one is horizontal to the orientation field and the other is vertical to that. Then these two kinds of gray variations aiming on the whole image are normalized. To segment the image, determine whether each block is a foreground area or a background area. This method fully utilizes the gray and direction characteristics of the fingerprint image, thus it can precisely separate the background area from the fingerprint image and the segmentation results are good.