多光谱掌脉和掌纹离焦图像融合方法

非接触条件下单模态手部图像纹理信息有限,不利于识别。本文提出利用同一装置在多光谱下分时快速获取掌纹和掌脉图像。通过掌纹图像在静脉图像中进行掌纹主线增强处理,达到增加纹理信息、改善识别效果的目的。控制掌纹、掌脉两幅图像获取间隔小于0.1s,忽略手掌细微空间移位,对获取的掌纹图像进行感兴趣区域(Region of interest,ROI)提取,并利用掌纹ROI坐标参数进行静脉图像的ROI提取。然后对两个ROI区域进行预处理,通过多层小波分解得到的掌纹高频信息快速定位掌纹主线。最后根据掌纹主线归一化后的高频分量,进行掌纹和掌脉小波系数的融合,最终得到在静脉纹理图像中增强掌纹主线纹理的融合图像。实验结果表明,融合后的图像中在保持静脉纹理信息原有状态下,掌纹主线纹理信息明显增加,识别效果得到改善。

Multispectral Palm-Vein and Palmprint Defocused Image Fusion Method

Texture information of the single mode hands image is not sufficient for recognition in non-contact condition. A single device under the multi-spectrum is put forward to rapidly capture the images of palm print and palm vein. The texture information is enhanced and the recognition performance is improved through enhancing the palm print mainlines of the vein image. Firstly, the interval of acquiring the palm print and palm vein images are limited to less than 0.1 s, and the tiny displacement of palm is ignored. And the ROI of the palm print image is determined, whose coordinates are used to determine the ROI of palm vein image. Then, the preprocessing of the two ROI regions are performed, and the palm print mainlines are rapidly determined via the palm print high-frequence information from multi-layer wavelet decomposition. Finally, wavelet coefficients of palm print and palm vein are fused according to the high frequency component of palm print mainline normalized, and the blended texture image with the enhanced palm print mainline in the vein texture image is acquired. The experiment results show that the information of palm print mainline texture is significantly enhanced in the fusion images in the condition of keeping the original state of the vein texture, and the recognition performance is improved.