A Secondary Positioning Algorithm of the Shoe Print

It proposed a positioning algorithm, which is based on secondary positioning of the shoe print image. After the pre-process was imposed on the image, the image is rotated by the algorithm of the vertex angle deflection according to the image feature. Then, the algorithm of equidistant vertical line as the second position is imposed on the image. Finally, the shoe image is in a perpendicular position. The experiment shows that, under various kinds of inclined angles, the algorithm proposed in this paper is effective. It lays a good foundation for the shoe print recognition in the criminal investigation.