Kinect传感器的彩色和深度相机标定

目的 针对现有的Kinect传感器中彩色相机和深度相机标定尤其是深度相机标定精度差、效率低的现状,本文在现有的基于彩色图像和视差图像标定算法的基础上,提出一种快速、精确的改进算法。方法 用张正友标定法标定彩色相机,用泰勒公式化简深度相机中用于修正视差值的空间偏移量以简化由视差与深度的几何关系构建的视差畸变模型,并以该模型完成Kinect传感器的标定。结果 通过拍摄固定于标定平板上的标定棋盘在不同姿态下的彩色图像和视差图像,完成Kinect传感器的标定,获得彩色相机和深度相机的畸变参数及两相机之间的旋转和平移矩阵,标定时间为116 s,得到彩色相机的重投影误差为0.33,深度相机的重投影误差为0.798。结论 实验结果表明,该改进方法在保证标定精度的前提下,优化了求解过程,有效提高了标定效率。

Calibration of Kinect sensor with depth and color camera

Objective Given the low efficiency and poor accuracy of the recent calibration method for the Kinect sensor with depth and color camera, we propose an improved algorithm that can quickly and accurately calibrate the color and depth camera of the Kinect sensor based on color and disparity images. Method The algorithm considers the features of color and depth simultaneously to improve the calibration of the Kinect sensor. The color camera was calibrated using Zhang's method, and the depth camera was calibrated using a Kinect disparity distortion correction model. This model represents the geometric relationship between disparity and depth and uses a spatially varying offset simplified by Taylor's formula that decays as Kinect disparity increases. Result The Kinect sensor was calibrated using multiple views of the calibration plane to obtain the color and disparity images that would be used to obtain the distortion parameters and the rotation and translation matrix between the two cameras. The spatial distortion parameter by Taylor's formula was streamlined to simplify the distortion correction model of the depth camera and to optimize the solution process. The reprojection error of the color camera was 0.33, whereas that of the depth camera was 0.798; the running tine of our calibration process was 116 s. Conclusion Experiments show that the proposed algorithm can ensure the accuracy and improve the efficiency of the calibration process.