This Article 
 Bibliographic References 
 Add to: 
Direct Gray-Scale Extraction of Features for Character Recognition
October 1993 (vol. 15 no. 10)
pp. 1053-1067

A method for feature extraction directly from gray-scale images of scanned documents without the usual step of binarization is presented. This approach eliminates binarization by extracting features directly from gray-scale images. In this method, a digitized gray-scale image is treated as a noisy sampling of the underlying continuous surface and desired features are obtained by extracting and assembling topographic characteristics of this surface. The advantages and effectiveness of the approach are both shown theoretically and demonstrated through preliminary experiments of the proposed method.

[1] C. Y. Suen, A. M. Berthold, and A. S. Mori, "Automatic recognition of handprinted characters--The state of the art,"Proc. IEEE, vol. 68, pp. 469-187, Apr. 1980.
[2] S. Kahan, T. Pavlidis, and H. S. Baird, "On the recognition of printed characters of any font and size,"IEEE Trans. Patt. Anal. Machine Intell., vol. PAMI-9, pp. 274-288, 1987.
[3] O. A. Zuniga and R. M. Haralick, "Corner detection using the Facet model," inProc. IEEE Comput. Vision Patt. Recogn. Conf.(Washington, DC), June 1983.
[4] R. M. Haralick, L. T. Watson, and T. J. Laffey, "The topographic primal sketch,"Int. J. Robotics Res., vol. 2, pp. 50-72, 1983.
[5] K. Rangarajan, M. Shah, and D. Van Brackle, "Optimal corner detector," inProc. Second Int. Conf. Computer vision, Tampa, FL, Dec. 5-8, 1988, pp. 90-94.
[6] M. H. Chen, D. Lee, and T. Pavlidis, "Residual analysis for feature detection,"IEEE Trans. Patt. Anal. Machine Intell., vol. 13, pp. 30-40, 1991.
[7] T. Pavlidis and G. Wolberg, "An algorithm for the segmentation of bilevel images, inProc. IEEE Comput. Vision Patt. Recogn. Conf.(Miami Beach), June 22-26, 1986, pp. 570-575.
[8] H. Murakami and B. V. K. Vijaya Kumar, "Efficient calculation of primary images from a set of images,"IEEE Trans. Patt. Anal. Machine Intell., vol. PAMI-4, pp. 511-515, 1982.
[9] C. M. Leung, "A practical basis set for Chinese character recognition, inProc. IEEE Computer Vision Patt. Recogn. Conf.(San Francisco), June 19-23, 1985, pp. 532-537.
[10] T. K. Peuker and D. H. Douglas, "Detection of surface-specific points by local parallel processing of discrete terrain elevation data,"J. Comput. Graphics Image Processing, vol. 4, no. 4, pp. 375-387, 1975.
[11] L. R. Nackman, "Two-dimensional critical point configuration graphs,"IEEE Trans. Patt. Anal. Machine Intell., vol. PAMI-6, pp. 442-450, 1984.
[12] A. V. Pogorelov,Differential Geometry. Groningen, the Netherlands: P. Noordhoff, (translated by L. F. Boron).
[13] A. Snyder and J. D. Love,Optical Waveguide Theory. Chapman and Hall, 1983.
[14] L. T. Watson, T. J. Laffey, and R. M. Haralick, "Topographic classification of digital image intensity surfaces using generalized splines and the discrete cosine transformation,"Comput. Vision Graphics Image Processing, vol. 29, pp. 143-167, Jan. 1985.
[15] R. M. Haralick, "Digital step edges from zero crossing of second directional derivatives,"IEEE Trans. Pattern Anal. Mach. Intell., vol. PAMI-6, pp. 58-68, 1984.
[16] P. Meer and I. Weiss, "Smoothed differentiation filters for images," Cent. Automat. Res., Univ. of Maryland, 1989.
[17] L. Wang and T. Pavlidis, "Direct gray scale extraction of features for character recognition," Tech. Rep., TR.92.06.01, Dept. of Comput. Sci., SUNY at Stony Brook, June 1992.
[18] J. Rocha and T. Pavlidis, "Shape analysis model with applications to a character recognition system," inProc. IEEE Workshop Application Comput. Vision(Palm Springs), Nov. 30-Dec. 2, 1992.
[19] W. J. Sakoda, J. Rocha, and T. Pavlidis, "Advanced research in machineprinted character recognition," Report to the U.S. Postal Service on Phase I Testing, Feb. 1992.
[20] D. Lee, T. Pavlidis, G. W. Wasilkowski, "A note on the tradeoff between sampling and quantization in signal processing,"J. Complexity, vol. 3, pp. 359-371, 1987.
[21] E. Joseph and T. Pavlidis, "Peak classifier for bar code waveforms," inProc. ICPR-11, vol. 2, Aug. 1992, pp. 238-241.

Index Terms:
direct feature extraction; characteristic assembly; gray-scale extraction; character recognition; continuous surface; topographic characteristics; feature extraction; optical character recognition
L. Wang, T. Pavlidis, "Direct Gray-Scale Extraction of Features for Character Recognition," IEEE Transactions on Pattern Analysis and Machine Intelligence, vol. 15, no. 10, pp. 1053-1067, Oct. 1993, doi:10.1109/34.254062
Usage of this product signifies your acceptance of the Terms of Use.