Jae-do KIM, Young-joon HAN, Hern-soo HAHN
Dept. of Electronic Engineering, Soongsil University, Seoul 156- 743, Korea
Abstract-This paper proposes the water level measuring method based on the image, while the ruler used to indicate water level is stained. The contamination of the ruler weakens or eliminates many features which are requir ed for the image processing. However, the feature of the color difference betwee n the ruler and the water surface are firmer on the environmental change compare to the other features. As the color differences are embossed, only the region o f the ruler is limited to eliminate the noise, and the average image is produced by using several continuous frames. A histogram is then produced based on the h eight axis of the produced intensity average image. Local peaks and local valley s are detected, and the section between the peak and valley which have the great est change is looked for. The valley point at this very moment is used to detect the water level. The detected water level is then converted to the actual water level by using the mapping table. The proposed method is compared to the ultras onic based method to evaluate its accuracy and efficiency on the various contami nated environments.
Key words-water level measurement； image processing； surveillance system； histogram analysis
Manuscript Number: 1674-8042(2010)01-0028-04
dio: 10.3969/j.issn.1674-8042.2010.01.05
References
[1]B. Y. Lee, B. Y. Park, 1999. Development of High Precision Undergrou nd Water Level Meter Using a Buoyant Rod Load Cell Technique. KSAFM, 1(1): 1-5 .
[2]J. H. Um, 2000. Inquiry of special quality of supersonic sensor for water level by non-contact. The Bulletin of Korea Environment Engine ers Association, 162: 30-36.
[3]S. Y. Hwang, 1999. The evaluation an uncertainly of measurement for underground water using an ultrasonic sensor. Process Control Instrume ntation Technology, (5): 102-107.
[4]Y. Takagi, A. Tsujikawa, M. Takato, T. Saito, M. Kaida, 1998. Develo pment of a non-contact liquid level measuring system using image processing. Water Science and Technology, 37(12): 381-387.
[5]Y. Takagi, T. Yoneoka, H. Mori, M. Yoda, A. Tsujikawa, T.Saito, 2001 . Development of a Water Level Measuring System Using Image Processing. The 1st IWA Conference on Instrumentation, Control and Automation, p. 309-316.
[6]N. Tsunashima, M. Shiohara, S. Sasaki, J. Tanahashi, 2000. Water lev el measurement using image processing. Information processing society of Japan. Research Report, Computer Vision and Image Media, 121(15): 11 1-117.
[7]M. Iwahashi, S. Udomsiri, 2007. Water Level Detection from Video wit h FIR Filtering. Proceeding of the 16th International Conference on Computer Com munication and Networks, p. 826-831.
[8]S. B. Park, Y. J. Han, H. S. Hahn, 2009. The water level detection a lgorithm using the accumulated histogram with band pass filter. World Academy of Science, Engineering and Technology, 56: 193-197.
[9]Roger. Y. Tsai, 1987. A versatile camera calibration technique for h igh-accuracy 3D machine vision metrology using off-the-shelf TV cameras and l enses. IEEE Journal of Robotics and Automation, 3(4): 323-34 4.
[10]Z. Zhang, 2000. A flexible new technique for camera calibration. IEEE Transaction on Pattern Analysis and Machine Intelligence, 22(11): 1330-1334.
[11]K. J. Kim, N. K. Lee, Y. J. Han, H. S. Hahn, 2007. Remote Detection and Monitoring of a Water Level Using Narrow Band Channel. The 6th WSEAS Intern ational Conference on Signal Processing, Robotics And Automation, p. 16-19.
[Full Text View]
