条纹图像瞬时频率的估计及其在相位展开中的应用

相位法是采用正弦投影光和移相技术的一种非接触测量方法。其中的关键总是是从主值相位恢复绝对相位，即相位展开问题。这是一个不适定问题。国内外的研究者进行了大量的研究工作，至今尚无满意的一般解决方法。本文利用相位法条纹图像的纹理特性，利用多频道Ｇａｂｏｒ小波滤波估计条纹图像的瞬时频率。通过检测瞬时频率幅值和方向的不连续来定位条纹纹理的边界，从而把相位场分割为一致的一区域。

Measuring Instantaneous Frequencies of Fringe Image and Its Application in Phase Unwrapping

Unwrapping a 2 D inconsistent principal value phase field of PMP(Phase Measuring Profilometry),that may contain regions of discontinuous phase,is an ill posed problem.Based on the globally nonstationary and locally coherent property of the fringe image texture,this paper measures the instantaneous frequencies by multiple channel wavelet like Gabor filters.By comparing the channel amplitude and phase responses,boundaries and discontinuities in texture can be detected,thus the phase field of PMP is segmented to consistent regions.The technique is demonstrated by application to synthetic and real PMP image of body models.