摘要
提出一种自动对焦技术,其调焦评价函数棗图像的平面微分平方和能够反映图像高频分量的能量。用计算平面微分平方和的方法在空间域上计算相邻像素亮度差值的平方和,对应于在频率域上计算图像高频分量的能量和,此值越大,图像对焦越准确。用平面微分平方和计算一行图像(N个像素)的调焦评价函数时,计算时间仅为2 (N -1)个时钟周期。
An automatic focusing technique is proposed. Its focusing evaluation function - square plane sum modulus difference (SPSMD) of image can reflect the energy of image high-frequency component. Calculating quadratic sum of adjacent pixel brightness difference in spatial domain with calculation of SPSMD method corresponds to calculating energy sum of image high-frequency component in frequency domain. The larger this value is, the more accurate the image focusing will be. When focusing evaluation functions for N pixels in a line are calculated with SPSMD, its calculation time is only 2(N-1) clock cycles.
出处
《光电工程》
EI
CAS
CSCD
北大核心
2004年第4期64-66,共3页
Opto-Electronic Engineering
