456
Proceedings of the 27th Chinese Control Conference
July 16-18, 2008, Kunming,Yunnan, China
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潘大夫, 汪渤
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E-mail: pandaful@bit.edu.cn
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An Improved Canny Algorithm
Pan Dafu, Wang Bo
Department of Automatic Control, School of Information Science and Technology, Beijing Institute of Technology, Beijng
100081,P. R. China
E-mail: pandaful@bit.edu.cn
Abstract: Image is analysed under multi-scale filtering in Canny algorithm frame. Firstly, scale multiplication is defined by
filter responses multiplication of two different scales. Then the modulus and orientation is determined by the similarity of ad-
jacent scales. Thirdly, a threshold value is chosen to eliminate false edge. Finally, the edge is obtained after non-maximum
suppression. Experimental results show the superior performance of the proposed algorithm in noise restrain and edge local-
ization than the traditional Canny algorithm.
Key Words: edge detection, scale multiplication, Canny algorithm
1 ��(Introduction)
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>?@A(References)
[1] MARR D� HILDRETH E.Theory of Edge Detection[J].
Proceeding of Royal Soc. London, 1980, B(27): 187-217.
[2] CANNY J. A computational app roach to edge detection[J].
IEEE Trans. on Pattern Analysis and Machine Intelligence,
1986, 8(6): 679-698.
[3] DEMIGNY D. On Optimal Linear Filtering for Edge De-
tection[J]. IEEE Trans. on Image Processing, 2002, 11(7):
728-737.
[4] TAGARE H D, FIGUEIREDO R J P,etal.On the Localiza-
tion Performance Measure and Optimal Edge etection[J].
IEEE Trans. on Pattern Analysis and Machine Intelligence,
1990, 12(12): 1186-1190.
[5] KOPLOWITZ J, GRECO V. On the Edge Location Error for
Local Maximum and Zero-Crossing Edge Detectors[J].
IEEE Trans. on Pattern Analysis and Machine Intelligence,
1994, 16(12): 1207-1212.
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