| With the rapid development of remote sensing technology,it has become more and more time saving and labor saving to carry out the work of forest resources survey and environmental change detection.However,due to the large area of remote sensing image acquisition time,weather conditions are very different,the remote sensing image mosaic brings great difficulties.At present,there is still no good method for accurate mosaic of remote sensing images with large background differences,most of the methods still depend on the brightness of the image,so there is a great deal of instability.On the other hand,the scale of data to process is more and more huge,so the efficiency is of great importance.Therefore,it is an urgent problem that how to accurately and efficiently integrate the remote sensing images with background differenceRemote sensing image mosaic refers to the method to mosaic the remote sensing images having overlapped area.Firstly,choosing a certain number of feature points in overlapped area,and matching them by feature matching algorithm;thus,we will get some matching points.Then,the transformation parameters composed of transformation matrix are calculated by the point transformation algorithm.Finally,the two images are mosaicked into a large imageImage registration and coordinate transformation are two important processes of remote sensing image mosaic in different backgrounds,which are studied respectively in this paper.In order to solve the problem of low matching accuracy and slow computation speed during the two processes,two new methods are proposed:a)Focused on the image registration,a method based on hierarchical convolutional features is proposed.This method adaptively obtains image features from CNN(Convolutional Neural Networks)and then sends the features derived from different images in different depth to CF(Correlation Filter)to compute the similarity between them.Therefore the locations of the feature points are computed with considering the different depth hierarchical convolutional features.b)In order to simplify the coordinate transform method,the cross points method is proposed.In this method,the feature of the remote sensing image is relatively stable,and the point transformation method can be simplified.According to the feature points location from the image registration,the transform parameters can be computed.Then the remote sensing images can be mosaicked by converting all pixels from one image to another.In this paper,we compare the remote sensing images under different weather and time conditions,and compare it with the traditional SIFT(Scale Invariant Feature Transform)remote sensing image mosaic method.The experiment results show the effectiveness and robustness of the proposed method by comparing to traditional mosaic method based on SIFT. |
