| 摘要 |
A method and apparatus for locating the centers of crosshair register marks and using the mark center locations to register the color film separations or other objects which bear the register marks. A digital picture is taken of each mark, and the picture image is transformed into a picture in which the pixels range between 0 and 1. Weighting windows are constructed and scanned over the pictures along the x and y axes to record the intensity level at each pixel location. Weighted summation calculations are then made to determine the intensity centroid location in x and y. A special screening technique is used to reject contributions of dirt, dust and other noise to enhance the accuracy.
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