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Ch45-I044963.fm  Page 222  Tuesday, August 1, 2006  3:55 PM
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               performed  because the number of edge pixels was reduced.





                                       (a)     (b)      (c)     (d)
                             Figure 5: Generated template images with selected edge pixels







                               (a)          (b)           (c)          (d)
                                                                       (d)
                               (a)
                                            (b)
                                                          (c)
                                 Figure 6: Matching results by the proposed method
                                                TABLE 2
                                   RECOGNITION RATE BY THE PROPOSED METHOD
                                Template      (a)   (b)   (c)   (A)    Ave.
                              Proposed method  100%  96%  90%   100%   96.5%
               The proposed  matching  method  was executed by using the generated  template  images  with  selected
               edge  pixels.  Fig. 6  shows  examples  of  matching  results  by the  proposed  method.  It  is  found  the
               inclined  target  image  areas  were  sought  successfully.  Over  90% recognition  rates  were  recorded  as
               shown  in  Table  2. The proposed  method  reduced  the large  number  of edge  pixels  for matching by
               using the selected  template table  and the method  recorded  the equal or higher  recognition  rates than
               using the template image with all edge pixels.

                                                TABLE 3
                                            MATCHING TIME [ms]

                                              (a)   (b)   (c)   (d)    Ave.
                                 Method 1     75    115   296    98    146.0
                                 Method2      71    121   223    99    128.5
                              Proposed method  67   110   142    89    102.0
               Table 3 shows the processing time to search for the target image area. The averaged processing time of
               the  proposed  method was  102ms. The proposed  method  that was used a template  image with  selected
               edge  pixels  was recorded  the  equal  or  faster  processing  time  than  the method 1 and method2. The
               proposed  method  can search  a target  component  even  if the  component  has a  free  location  and an
               inclination and the method is supposed to be realized the high-speed matching for industrial use.


               REFERENCES

                 Hollond J.H. (1975). Adaptation  in Natural  and Artificial  Systems, The Univ. Michigan Press
                 Saitoh  F.  (2003).  Rotation  Invariant  Image  Matching  Based  on  Correlation  of  Curvature
                 Distribution. Electrical Engineering  in Japan  145:4, 975-981.
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