基于平台参数的航空光学图像镶嵌算法研究

Algorithm of aerial optical image mosaicing based on platform parameters

航空图像的镶嵌在图像情报分析中有着重要的军事意义,通过分析机载航空光学成像的特点及平台参数,结合光学成像的透视投影模型,推导出倾斜投影下从像素坐标到世界坐标的统一坐标变换关系,并在世界坐标下计算图像的大致镶嵌区域,实现图像粗镶嵌;再提取粗镶嵌区域中的SIFT特征,计算镶嵌图像之间的变换模型参数,实现图像精确镶嵌。实验结果表明,算法在运算速度和镶嵌精度上取得了较好的效果。

Mosaicing of aerial images is important to image intelligence analysis in military. In this paper , characteristic of aerial optical imaging and parameters of aerial platform are analyzed. Based on the principle of perspective projection model, the coordinate transform relationship between pixel coordinate and world coordinate is mainly deduced under oblique projection, and rough mosaicing regions of the two images are calculated under world coordinate, in this step, not much attention is paid to the accuracy. Then, SIFT algorithm is employed to extract invariable feature from the rough mosaicing regions, and calculate the transform model parameters of the two images accurately, in order to realize mosaicing refinedly. Experiments results of field images show that the algorithm is time efficient and fine-results in mosaicing.