基于傅里叶变换的干涉条纹对比度增强算法

A contrast enhancement algorithm of interference fringes based on 2-D DFT

论述了一种干涉条纹对比度增强的算法。将二维离散傅里叶变换后得到的干涉条纹图像频谱分布,应用带通滤波器滤波。滤波过程中,在保持通带内相位谱不变的条件下,增大了通带内幅频谱的值。然后对滤波后的频谱分布进行逆二维离散傅里叶变换,可得到对比度增强后的干涉条纹图像。实验表明,该方法在保持干涉条纹中心线空间位置不变的情况下,可以有效地增强干涉条纹的对比度。

The paper discusses on a contrast enhancement algorithm of interference fringe pattern, which includes following three steps：spectrum of interference fringe pattern is obtained by two-Dimensional Discrete Fourier Transform（DFT）, then filters with bandpass filter; during filtering, the phases spectrum in the bandpass remains no change,the values of amphtude spectrum are amplified; the spectrum after filtering is transformed by 2-D reverse DFT to obtain the interference fringe pattern, whose contrast has been enchanced. The results show that the algorithm can efficiently enhance the contrast of fringes without changing the space position centers of interference fringes.