Li Huaizhou, Wang Shuaijun, Bai Zhenpeng, Wang Hong, Li Sen, Wen Shupei
College of Building Environmental Engineering, Zhengzhou University of Light Industry, Zhengzhou 450001, China.
Sensors (Basel). 2023 Aug 24;23(17):7372. doi: 10.3390/s23177372.
Thermal infrared imaging is less affected by lighting conditions and smoke compared to visible light imaging. However, thermal infrared images often have lower resolution and lack rich texture details, making them unsuitable for stereo matching and 3D reconstruction. To enhance the quality of infrared stereo imaging, we propose an advanced stereo matching algorithm. Firstly, the images undergo preprocessing using a non-local mean noise reduction algorithm to remove thermal noise and achieve a smoother result. Subsequently, we perform camera calibration using a custom-made chessboard calibration board and Zhang's camera calibration method to obtain accurate camera parameters. Finally, the disparity map is generated using the SGBM (semi-global block matching) algorithm based on the weighted least squares method, enabling the 3D point cloud reconstruction of the object. The experimental results demonstrate that the proposed algorithm performs well in objects with sufficient thermal contrast and relatively simple scenes. The proposed algorithm reduces the average error value by 10.9 mm and the absolute value of the average error by 1.07% when compared with the traditional SGBM algorithm, resulting in improved stereo matching accuracy for thermal infrared imaging. While ensuring accuracy, our proposed algorithm achieves the stereo reconstruction of the object with a good visual effect, thereby holding high practical value.
与可见光成像相比,热红外成像受光照条件和烟雾的影响较小。然而,热红外图像的分辨率通常较低,且缺乏丰富的纹理细节,这使得它们不适用于立体匹配和三维重建。为了提高红外立体成像的质量,我们提出了一种先进的立体匹配算法。首先,使用非局部均值降噪算法对图像进行预处理,以去除热噪声并获得更平滑的结果。随后,我们使用定制的棋盘格校准板和张氏相机校准方法进行相机校准,以获得准确的相机参数值。最后,基于加权最小二乘法,使用SGBM(半全局块匹配)算法生成视差图,从而实现物体的三维点云重建。实验结果表明,该算法在具有足够热对比度和相对简单场景的物体上表现良好.与传统SGBM算法相比,该算法将平均误差值降低了10.9毫米,平均误差绝对值降低了1.07%,提高了热红外成像立体匹配精度。在保证精度前提下,该算法实现了物体的立体重建,视觉效果良好,具有较高的实用价值。