| 摘要 |
PROBLEM TO BE SOLVED: To accurately recognize a irradiation field by recognizing a region surrounded by an irradiation field contour candidate line except an irradiation field contour candidate line judged to be an error by an irradiation field contour candidate line correct/ error decision means performing a correct/error judgment as an irradiation field. SOLUTION: Whether any of irradiation field contour candidate lines stored in an irradiation field contour candidate storage means is an error or not is discriminated. The irradiation field contour candidate line which is not discriminated as an error is discriminated as a right one and is determined for an irradiation field contour line. Further, the irradiation field contour lines are determined in the same way also for other groups and regions surrounded by the determined irradiation field contour lines are discriminated as areas within irradiation field. When an irradiation field contour candidate line is erroneously detected as shown in a figure, for instance, and two of the erroneously detected irradiation field contour candidate line and a rightly detected irradiation field contour candidate line are read, the erroneously detected irradiation field contour candidate line which is short in distance is discriminated to be an error because degrees of parallelization are equal but distances from an image center are different, and a right irradiation field recognition can be performed. |
