【作者】 王鹏；

【Author】 Wang Peng (College of Electronics and Information Engineering,Tongji University,Shanghai 201804 China)

【机构】 同济大学电子与信息工程学院；

【摘要】 自动调焦技术已经得到了广泛应用,但目前不少老式监控系统仍需要手动实现调焦,使用并不方便。以美国模拟器件公司的高性能定点 DSP 芯片 ADSP-BF533为处理核心,设计了一种可以为老式电视监控摄像机增加自动调焦功能的嵌入式装置。使用了两种步长和调焦评价函数进行粗精结合自动调焦,既加快了调焦速度,克服了图像噪声的影响,又能满足对调焦精度的要求。当被摄景物清晰度下降时,系统会自动开始新一轮调焦。更多还原

【Abstract】 Auto-focus techniques have been widely used.Whereas many old-fashioned TV monitoring systems still have to be focused manually,that’s not convenient.ADSP-BF533 is a high-level fixed-point DSP of Analog Devices Inc.Using it as processing core,an embedded system is designed,which can add auto-focus function for old-fashioned TV monitoring video camera.2 different steps and focus evaluation functions were used in this system. So that focus time is decreased greatly,image noise effect also is alleviated,and focus accuracy keeps excellent. When object’s sharpness decreases,new auto-focus routine is launched automatically.更多还原