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http://dx.doi.org/10.15701/kcgs.2018.24.3.43

Shadow Removal from Scanned Documents taken by Mobile Phones based on Image Local Statistics  

Na, Yeji (Department of Software, Sejong University)
Park, Sang Il (Department of Software, Sejong University)
Publication Information
Journal of the Korea Computer Graphics Society / v.24, no.3, 2018 , pp. 43-48 More about this Journal
Abstract
In this paper, we present a method for removing shadows from scanned documents. Compared to the existing methods such as one based on image pyramid representation or adaptive thresholding, our method produces more robust and higher quality results. The basic idea of the approach is to use the local image statistics and to separate interesting regions from the image such as the regions around letters and figures. For the separated regions, we adaptively adjust the local brightness and contrast, and apply the sigmoid function to the intensity values as well to enhance the clarity of the image. For separated the other empty regions, we apply the gradient-base image hole filling method to fill the region with smooth color change.
Keywords
Image Processing; Shadow Removal; Image Enhancement; Image Restoration;
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1 Nemonic, http://mangoslab.com, Mangoslab Co. Ltd
2 G. Finlayson, M. Drew, and C. Liu, "Intrinsic images by entropy minimization," In Proc. ECCV, vol. III, pp. 582-595, 2004
3 G. Finlayson, S. Hordley, and M. Drew, "Removing shadows from images," In Proc. ECCV, vol. IV, pp. 823-836, 2002
4 C. Fredembach and G. Finlayson, "Hamilonian path based shadow removal," In Proc. BMVC05, 2005
5 C. Fredembach and G. Finlayson, "Simple shadow removal," In Proc. ICPR, vol. I, pp. 832-835, 2006
6 A. Mohan, J. Tumblin, and P. Choudhury, "Editing soft shadows in a digital photograph," IEEE Computer Graphics Applications, vol. 27, no. 2, pp 22-31, 2007   DOI
7 B. Oh, M. Chen, J. Dorsey, and F. Durand, "Image-based modeling and photo editing," In Proc. SIGGRAPH 2001, pp. 433-442, 2001
8 T. Wu, C. Tang, M. Brown and H. Shum, "Natural shadow matting," ACM Transactions on Graphics, vol 26, no. 2, article no 8, 2007
9 Y. Shor and D. Lischinski, "The shadow meets the mask: Pyramid-based shadow removal," Computer Graphics Forum, vol. 27, no. 2, pp. 577-786, 2008   DOI
10 P. Perez, M. Gangnet and A. Blake, "Poisson image editing," In Proc SIGGRAPH 2003, pp. 313-318, 2003