NIOSⅡ自动对焦实现研究

Implementation of Auto-Focusing Based on NIOSⅡ

为了在嵌入式视觉系统中获得清晰图像,文中设计了一个基于现场可编程门阵列的自动对焦硬件系统,在现场可编程门阵列上采用可编程片上系统技术设计了以嵌入式软核处理器NIOSⅡ为核心的自动对焦片上系统,研究了图像数据访问算法和自动对焦评价函数算法,设计了自动对焦系统软件.实验结果表明:基于NIOSⅡ的自动对焦方法可行;对焦精度和对焦速度受到对焦区域大小的影响.基于NIOSⅡ的自动对焦可作为嵌入式视觉系统中自动对焦的一种实现方法.

In order to get a sharp image in the embedded vision system,an Auto-focusing hardware system based on FPGA was devised.In the FPGA,SOPC technology was used to design an Autofocusing SOC with NIOS II embedded processor as the core.The image data access algorithm and the auto-focus evaluation function algorithm were studied.Finally the Auto-focusing system software was designed.Experimental results show that the Auto-focusing based on NIOS II is feasible,and that the focusing accuracy and focusing speed are affected by the size of focusing area.Therefore,the Autofocusing based on NIOS II can be used as a method for Auto-focusing in the embedded vision system.