关键词: 配准, 互功率谱, 互信息, 傅里叶频谱

Abstract: Image registration is the key step of image analysis with images from multiple resources.It is also the foundation of image application.The advantages of frequency approaches to registration are rapidness and high precision.The frequency approach proposed by P.Vandewalle outperforms previous frequency methods and some special domain methods.In this paper，it is improved to be faster and get higher precision.Finally，a frequency domain approach based on mutual information to image registration is presented by using half the amplitude of the Fourier transform and mutual information theory.

Key words: registration, cross-power spectrum, mutual information, amplitude of the Fourier transform