在分析目前已有的一些影像数据更新方法的基础上,提出一种影像增量动态更新与融合的新方法,该方法首先利用图幅格网索引图和新影像数据定位更新变化图幅和范围,然后对不同时期的影像数据进行镶嵌式的增量更新。针对不同时相影像数据间的色彩差异进行色彩均衡处理,而对于不同时相影像数据镶嵌边缘存在像元突变效应进行了基于卷积和反距离加权的图像平滑融合处理。经试验论证,该方法在计算效率和镶嵌效果上具有优势,可用于局部地区的影像更新.
Based on the analysis of the existing methods of image update, a new method for image update and fusion in an incremental and dynamic way is proposed. The method firstly locates the changing map sheets and areas with grid index maps and incrementally updates the local parts of original data with images of different phrases through mosaic technique. Then it conducts color balance manipulation to reduce color variation of different images. The image smooth process based on convolution and distance-inverse weighted method is also applied to solve the pixel mutation effects existed in the transition zone. The method with a case study and corresponding analysis is illustrated. The result shows that the method has high computational efficiency and good mosaic effect. The method exhibits satisfied practicability in local scope incremental image updating and successfully solves the dynamic update problems.