基于小波变换和形态学操作的指纹图像编码研究

Fingerprint Image Coding Based on Wavelet Transform and Morphological Dilation

在深入研究EZW和MRWD方法基础上,提出了一种结合指纹方向图的指纹压缩算法。首先将指纹图像按纹理信息进行分块,然后对指纹图像中不同的方向图块采用不同的结构元素来实现各子带重要系数的膨胀操作以对其进行检测、提取和编码。该方法除了具有EZW的优点外,还有效地提高了MRWD方法在处理指纹图像时的性能。实验结果证实了该方法的高效性。

We propose a fingerprint coding algorithm based on directional image, EZW and MRWD algorithm. We first divide a fingerprint image into several blocks according to its directions, and then use different structural elements for morphological dilation according to different directional blocks to extract the clustered significant coefficient in different sub-bands from low fre quency to high frequency. The proposed algorithm not only has all the merits of EZW, but also rids some deficiencies in MRWD algorithm. Experiment has proved the validity of the algorithm.