基于多通道滤波技术的散斑条纹图正则化方法

A New Method for Speckle Fringe Pattern Normalization Based on Multichannel Filtering

在光测力学中,条纹图正则化是进一步提取条纹位相信息的重要基础。对于散斑条纹图来说,正则化的过程还需能够有效地抑制散斑噪声。本文提出一种基于多通道滤波技术的散斑条纹图正则化方法。通过使用多个Gabor滤波通道对散斑条纹图进行滤波,并且引入与条纹对比度有关的权重因子把各个滤波通道的滤波结果叠加起来,最终得到滤除了散斑噪声的正则化条纹图。数值模拟和实验结果表明,该方法在将散斑条纹图正则化的同时能够有效地滤除条纹图中的散斑噪声,为进一步提取条纹位相奠定了良好的基础。

Normalization is an important basis for phase extraction from fringe patterns in photomechanics. For a speckle fringe pattern,this task is difficult since fringe pattern is strongly spoiled by speckle noise. In this paper,an algorithm for speckle fringe pattern normalization is presented based on multichannel filtering. Speckle fringe pattern was first filtered by multichannel Gabor filters,then,the filtering results were weighted added up,which is depended on the fringe modulation. Finally,a normalized fringe pattern was obtained. Simulation and experimental results show that the speckle fringe pattern is well normalized as well as the speckle noise in the fringe pattern is removed efficiently. This method provides a good basis for further extracting phase from a fringe pattern.