Application of Deformable Grid in Image Recognition
Yan Ji-kun①; Zhang Zhen②; Zheng Hui①
①LISP The South-west Inst. of Electron. & Telecom. Tech., Chengdu 610041 China;②The Information Engineering University of Zhengzhou Zhengzhou 450002 China
Abstract:Grid feature is a popular feature extraction scheme in image recognition, and usually higher performance could be obtained with the help of deformable template, espe-cially in such difficult image recognition tasks as character recognition, digit recognition, logo recognition etc. The critical shortcoming of deformable template is time-consuming. In this paper the method of deformable grid is proposed to compensate for the shortcoming of deformable template. Firstly certain grid must be superimposed on image, then unlike de-formable template where deformation is applied to image, various deformations are applied to grid. Because the number of grid is much less than that of pixels in image, the method is much more timesaving comparing to deformable template. The approximate equality of deformable template and deformable gird is also analyzed. The method is evaluated by two image recognition experiments, namely, logo recognition and off-line Chinese character recognition. The improvements in recognition rate by 7.3% in first experiment, and 5.8% in second one are obtained by the use of deformable grid.