【摘要】 分析了梯度函数、频谱函数和熵函数在自动对焦技术中的作用 ,并研究了评价函数的性能 .实验表明 ,梯度函数具有运算速度快的优点 ,适用于需要实时成象的场合 ;而频谱函数具有灵敏度高、曲线尖锐的特点 ,能够满足高精度的要求更多还原

【Abstract】 Gradient function,frequency spectrum function and entropy function are main tools for evaluating digital image sharpness.This paper discussed their application in autofocus technology and studied feature of evaluation functions.Experimental results show that gradient function′s advantage is rapid speed and it can be used in real time process,and frequency spectrum function has good sensibility and is qualified for higher accuracy.更多还原