Label Restoration Using Biquadratic Transformation

다국어 초록 (Multilingual Abstract)

Recently, there has been research to use portable digital camera to recognize objects in natural scene images, including labels or marks on a cylindrical surface. In many cases, text or logo in a label can be distorted by a structural movement of the object on which the label resides. Since the distortion in the label can degrade the performance of object recognition, the label should be rectified or restored from deformations. In this paper, a new method for label detection and restoration in digital images is presented. In the detection phase, the Hough transform is employed to detect two vertical boundaries of the label, and a horizontal edge profile is analyzed to detect upper-side and lower-side boundaries of the label. Then, the biquadratic transformation is used to restore the rectangular shape of the label. The proposed algorithm performs restoration of 3D objects in a 2D space, and it requires neither an auxiliary hardware such as 3D camera to construct 3D models nor a multi-camera to capture objects in different views. Experimental results demonstrate the effectiveness of the proposed method.

참고문헌 (Reference)

1 R. Duda, "Use of the Hough transform to detect lines and curves in pictures" 11-15, 1972

2 Qixiang Ye, "Text detection and restoration in natural scene images" 18 (18): 504-513, 2007

3 Z. C. Li, "Splitting-integrating method for normalizing images by inverse transformations" 16 (16): 678-686, 1992

4 Wu Guo-Ping, "Slant correction of Vehicle License Plate Image" 919-922, 2005

5 Y. Y. Tang, "Nonlinear shape restoration by transformation models" 14-19, 1990

6 Q. L Gu, "Mathematical methods for font generation and shape design of characters" 1-14, 1991

7 Y.Y. Tang, "Image transformation approach to nonlinear shape restoration" 23 (23): 155-172, 1993

8 Rafael C. Gonzalez, "Digital Image Processing" Pearson 2010

9 Y.Y. Tang, "Conversion of Chinese characters by transformation models" 293-297, 1988

10 James D. Foley, "Computer Graphics Principles and Practices in C, 2nd Edition" Addison Wesley 1997

11 Z.C. Li, "A comparative study of nonlinear shape models for digital processing and pattern recognition" 20 (20): 858-871, 1990