Research On Vein Image Acquisition Based On SOPC

With the rapid development of information technology, information security has been widely concerned by the whole society, especially more requests have been put forward on the subject of protecting personal information. When the traditional methods of individual identification expose their defects gradually, biometrics identification technologies have become quite popular due to its advantage of high accuracy, high security and convenience on operation, and vein identification is one of biometrics identification technologies.This thesis takes the hand vein image as background, and aims to realize the vein image capturing system. A research on the hardware system construction of capturing device, image quality assessment methods and near-infrared light source intensity controlling is addressed in this thesis. And based on the conditions mentioned above, image quality assessment result is used to control the light intensity, therefore, the capturing device can get vein image of high quality.In this article, System on Chip (SOC) technology and System on a Programmable Chip (SOPC) technology have been introduced respectively. By comparing the different ways of implementation, the SOPC technology has been described. Then, technology and development environment, also flow of soft-core SOPC based on Nios Ⅱ have been set forth in detail.On the aspect of system construction, it is developed based on SOPC. According to the characteristics of vein images capturing system, other peripheral equipments, image sensor MT9V032and near-infrared light through filter, have been selected and analyzed, also, LED light source array and driving circuit has been designed. Meanwhile, the core module and transmission module have been designed according to the request of system.The last part of this paper is applied to realize the functions of the achieved system structure. IP cores for different module of system have been designed respectively, and the custom hardware system was generated in the SOPC Builder. Then it comes to the comments of image quality, a large number of summary and analysis have been done, and for NIR image, a new method of image quality assessment has been proposed, which is based on no reference objective mode. Finally, this method is taken to be the standard for realizing the self-optimizing control of NIR LED arrays’luminous intensity.