The Research Of Embedded Whole Hand Shaped Features Collector

With the development of society, more and more emphasis has been paid on personal identity authentication in criminal investigation, immigration control, bank etc. The Personal Identity Authentication System (PIAS) has converted from single pattern to multi-pattern, and the identification authentication equipment has leaned from large-scale to small-scale, portable and low-cost, all these changes are mostly due to the progress of the Embedded Micro Processor Unit (EMPU) in resent years.In this paper, an whole hand shape feature abstraction method is proposed and an abstraction devise is designed, which is the precondition of the implementation of the Hand Shape Feature Recognition-a new multi-mode biological recognition technology, which merges together the basic feature of fingerprint, palm print and hand shape.This device's scheme is determined as a design frame of CCD camera+A/D converter chip+ARM chip by comparing a large number of the image collection scheme. The system consists of four components:an Image collection Module for A/D conversion of the image signals, a processor module for temporary and pre-processing the digital image signals, an Ethernet transmission module for transmission of digital image signals, and a keyboard display module for selection of information and display of pictures.This device combine with the popular embedded Linux system to implement the simplicity and integration of the circuit, to improve the flexibility of the system greatly, and to make the system a better real-time and portability at the same time.Under the frame, this system use ARM9 processor chip S3C2440A produced by Samsung, which could realize the input of digital image signals and the synchronization signals, and the video decoding chip configuration conveniently by connecting the camera interface(CAMFI) to SAA7113H which is video decoder chip, and image data is transmitted to server by Ethernet after simple image processing. In the software design, according to the characteristics of the embedded Linux system and the image collection system, the system is determined as based on Linux-2.6.29 kernel, use V4L2 as model to write the drive of SAA7113H and the application programs and use stream socket to write the transmit code. Based on the technical line in above, the design of hardware system is completed, the PCB board of video decoding module is drawn, development environment is established and part of the collection programs and the code of Ethernet transmission program are written, which would have high reference value for follow-up researches.