Institute of Biomedical Instrument, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China.
Med Eng Phys. 2009 Nov;31(9):1173-81. doi: 10.1016/j.medengphy.2009.07.016. Epub 2009 Sep 25.
As the needs for various kinds of body surface information are wide-ranging, we developed an imaging-sensor integrated system that can synchronously acquire high-resolution three-dimensional (3D) far-infrared (FIR) thermal and true-color images of the body surface. The proposed system integrates one FIR camera and one color camera with a 3D structured light binocular profilometer. To eliminate the emotion disturbance of the inspector caused by the intensive light projection directly into the eye from the LCD projector, we have developed a gray encoding strategy based on the optimum fringe projection layout. A self-heated checkerboard has been employed to perform the calibration of different types of cameras. Then, we have calibrated the structured light emitted by the LCD projector, which is based on the stereo-vision idea and the least-squares quadric surface-fitting algorithm. Afterwards, the precise 3D surface can fuse with undistorted thermal and color images. To enhance medical applications, the region-of-interest (ROI) in the temperature or color image representing the surface area of clinical interest can be located in the corresponding position in the other images through coordinate system transformation. System evaluation demonstrated a mapping error between FIR and visual images of three pixels or less. Experiments show that this work is significantly useful in certain disease diagnoses.
由于对各种体表信息的需求广泛，我们开发了一种成像传感器集成系统，该系统可以同步获取高分辨率三维（3D）远红外（FIR）热像和真实彩色体表图像。所提出的系统将一个 FIR 相机和一个彩色相机与 3D 结构光双目轮廓仪集成在一起。为了消除来自 LCD 投影仪的强光直接照射眼睛对检查者造成的情绪干扰，我们开发了一种基于最佳条纹投影布局的灰度编码策略。采用自加热棋盘格对不同类型的相机进行标定。然后，我们根据立体视觉思想和最小二乘二次曲面拟合算法对 LCD 投影仪发出的结构光进行了标定。之后，精确的 3D 表面可以与未失真的热像和彩色图像融合。为了增强医学应用，通过坐标系变换，可以将温度或彩色图像中代表临床感兴趣区域（ROI）的区域定位到其他图像中的相应位置。系统评估表明 FIR 与视觉图像之间的映射误差在三个像素或以下。实验表明，这项工作在某些疾病诊断中具有重要意义。
