A combination of two sets of ideas, i.e., high-precision measurement for small parts and making the whole from pieces, is valid approach for large size parts vision measurement. Image mosaic is one of essential technologies. In order to choose a suitable algorithm, the existing image mosaic algorithms were summarized and classified. The flows of the new algorithms were analyzed. It is reported that image mosaic algorithms can be classified into two main groups, and can be further sub classified. These new algorithms also belong to the two main groups.