According to the characteristics of the image mosaic of the large-scale workpiece measurement system,an improved fast mosaic algorithm with high accuracy is proposed by combining the feature extraction with the template matching. In this algorithm,first,the feature points of two adjacent images are extracted by using the multiscale Harris operator. Then,in the first image,the templates are identified according to the distribution of the feature
points; and in the second image,the matching blocks are chosen by means of the template matching. Finally,the matching feature points in the matching blocks are detected by the feature matching,and the mosaic is thus completed. Experimental results show that the proposed algorithm greatly reduces the computation amount of the mosaic,effectively avoids the false matching which is easy to occur due to scarce features and large-scale similar areas of the workpiece,thus meeting the requirements of the measurement system.