Abstract: The positions of SIFT points and scale value were composed to a vector, which was used to the dataset of cluttering algorithm. The parameters of global affine transformation were got by the clustering algorithm, which was used to filter the matched point. For the image mosaic problems of the existing algorithms, a grid-selection mosaic algorithm was proposed. The visual skeleton and the image mosaic offset were put forward to measure the stability of the filtering and the performance of mosaic algorithm. Experimental results indicate that the methods proposed can overcome the problems of traditional algorithms and have better stability and accuracy.