提出了一种嵌入到常规几何标定过程中的非线性校正算法.该方法通过相位获取投影图案与拍摄图像对应点之间的亮度关系,进而确定系统的非线性亮度响应.该算法在几何标定进行的同时,无需调整系统设置或投影额外的结构光图案,直接导出用于非线性预补偿的灰度查找表.实验结果表明,校正后的相位误差比校正前减少了约95%.

In this paper,we present an algorithm,which is incorporated into geometrical calibration,to accurately and efficiently calibrate and correct the nonlinearity.The proposed method utilizes phase to obtain the intensity correspondences between projected patterns and recorded images.Based on the intensity correspondences,the nonlinear response of the system is further retrieved.Along with geometrical calibration,without adjusting setup or using any additional specially-designed structured light patterns,a look-up table for correcting the nonlinear response is directly and accurately derived,and is applied to the intensities of the patterns before projection.Experiments show that the root mean square of the phase error is significantly reduced by a factor of 21.8 times.