红外热像仪标定方法

Research on Algorithm of Infrared Thermal Camera Calibration

为了由红外图像得到目标的经度、纬度和高度信息,对目标精确定位,提出一种新的红外热像仪标定方法。以针孔成像模型作为红外热像仪成像模型,选择小热源作为标定点,以WGS-84坐标系作为世界坐标系,引入北东天(NEU)坐标系,先通过借鉴主动视觉的思想控制热像仪绕光心旋转得到外部参数,然后借助GPS接收机测得标定点世界坐标,利用这些标定点的像素坐标和世界坐标由最小二乘估计求解内部参数。实验表明新方法精度高、成本低,适合于实际应用。

A new method was proposed in order to obtain the longitude, the latitude and the altitude of the target in a infrared image. In this method the pin-pole imaging model was used as the infrared thermal camera imaging model , small thermal bodies were chose to be the calibration points, the WGS-84 coordinates was used as the world coordinates, and NEU coordinates was imported. The method consisted of two steps. First, the extern parameters were gained by means of using active vision for reference to rotate the infrared thermal camera around its light-center. Second, the world coordinates of these calibration points were measured by a GPS receiver, and interior parameters were obtained by way of least squares estimation using the pixels coordinates and the world coordinates. Experiment shows that this new method with low cost is high precise and suitable for practical application.