基于动态因子自适应搜索算法的自动调焦研究

Auto Focusing Research Based on Dynamic Factor Adaptive Search Algorithm

为提高自动调焦的性能,采取动态因子自适应搜索算法。首先,建立分辨率逐步递减的调焦窗口,以减少非聚焦区域对调焦评价函数计算的影响;其次,通过动态调焦因子方法修正目标变化对清晰度评价函数的影响;最后,通过适应变步长爬山算法结合清晰度评价函数搜索聚焦点,提高搜索速度和调焦精度。试验仿真显示,本文提出的算法获得的图像清晰,其性能受噪声影响小,可满足自动调焦中对稳定性、实时性和清晰度的要求。

In order to improve the performance of auto focusing algorithm, dynamic factor adaptive search algorithm is proposed. Firstly, the focus window was established with the gradual decrease of resolution, and non focusing region effect of evaluation function was reduced. Secondly, dynamic focusing factor method was corrected the target changed region, which influenced evaluation function. Finally, adaptive variable step size hill-climbing algorithm combined with the clarity evalua- tion function were searched focus ,which improved the searching speed and the accuracy of focusing. Experiment simulation shows that focused image is clear, noise is less than other algorithms, so that it can satisfy the requirement of stability, real- time and definition in auto focusing.