Abstract
This paper describes a new approach for a contour-tracing algorithm targeting a low-power smart camera for industrial inspection. This embedded system consists of the three major components: CMOS sensor, FPGA and microprocessor. By analysing a linear-time algorithm used for simultaneously labelling connected components and their contours, two independent tasks could be identified. By efficiently assigning these two parts to the FPGA and the microprocessor achieving high-speed real-time operation is possible. The novelty of the proposed method is the development of a sequential co-processing algorithm for the FPGA. A Contour-Neighbourhood 3 × 3 filter kernel for converting the grey-level data to an intermediate representation containing directional information was added into an FPGA image-processing design. This pre-processed data is then provided to a software component which is executed on a microprocessor. The final result of this analysis is a sorted list of contour points for each object in the image. Further increases of the data throughput and the workload of the hardware resources are achievable by pipelining the subtasks of consecutive images. The runtime behaviour of this parallel operation is sufficient for meeting the real-time requirements of an industrial 2D measurement system.
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References
Chang, F., Chen, C.J.: A component-labeling algorithm using contour tracing technique. In: Proceedings of the seventh international conference on document analysis and recognition, pp. 741–745 (2003)
Chang, F., Chen, C.J., Lu, C.J.: A linear-time component-labeling algorithm using contour tracing technique. Comput. Vis. Image Underst. 93(2), 206–220 (2004). doi:10.1016/j.cviu.2003.09.002
Haig, T.D., Attikiouzel, Y.: An improved algorithm for border following of binary images. In: Proceedings of the 1989 European conference on circuit theory and design, pp. 118–122 (1989)
Hedberg, H.: Image processing architectures for binary morphology and labeling. PhD thesis, The Department of Electrical and Information Technology, Lund University (2008)
Hedberg, H., Kristensen, F., Owall, V.: Implementation of a labeling algorithm based on contour tracing with feature extraction. In: Proceedings of the 2007 IEEE international symposium on circuits and systems (ISCAS), pp. 1101–1104 (2007)
Ma, N., Bailey, D., Johnston, C.: Optimised single pass connected components analysis. In: Proceedings of the 2008 international conference on ICECE technology, pp. 185–192 (2008). doi:10.1109/FPT.2008.4762382
Marvell Technology Group Ltd. http://www.marvell.com (2009)
Pavlidis, T.: Algorithms for graphics and image processing. Computer Science Press (1982)
Ratnayake, K., Amer, A.: A real-time implementation of chaotic contour tracing and filling of video objects on reconfigurable hardware. In: Proceedings of the 2007 IEEE international conference on systems, man and cybernetics ISIC., pp. 1089–1094 (2007). doi:10.1109/ICSMC.2007.4414062
Ratnayake, K., Amer, A.: Sequential, irregular and complex object contour tracing on fpga. In: Proceedings of the 2007 IEEE international conference on image processing ICIP, pp. 165–168 (2007). doi:10.1109/ICIP.2007.4379791
Rosenfeld, A.., Kak, A.C.: Digital picture processing. Academic Press Inc., Orlando, FL, USA (1982)
Suzuki, S., Be, K.: Topological structural analysis of digitized binary images by border following. Comput. Vis. Graph. Image Process. 30(1), 32–46 (1985). doi:10.1016/0734-189X(85)90016-7
Trein, J., Schwarzbacher, A.T., Hoppe, B., Noffz, K.H., Trenschel, T.: Development of a FPGA based real-time blob analysis circuit. In: Proceedings of the 2007 international conference on system and safety (2007)
van Dyck, W., Smodič, R., Hufnagl, H., Berndorfer, T.: High-speed jpeg coder implementation for a smart camera. J. Real-Time Image Process. 1(1), 63–68 (2006). doi:10.1007/s11554-006-0012-y
XILINX Inc. http://www.xilinx.com (2009)
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Jordan, H., van Dyck, W. & Smodič, R. A co-processed contour tracing algorithm for a smart camera. J Real-Time Image Proc 6, 23–31 (2011). https://doi.org/10.1007/s11554-010-0182-5
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DOI: https://doi.org/10.1007/s11554-010-0182-5