IMAGE DISTORTION CORRECTION METHOD, AND THREE-DIMENSIONAL SHAPE MEASURING INSTRUMENT

摘要

PROBLEM TO BE SOLVED: To correct a distortion of an image even when generation factors of the distortion are combined multiply, and to determine a correction amount by simple work. SOLUTION: A standard pattern plate expressed with a checkered pattern is imaged by a TV camera (S1). Four or more of reference points corresponding to a basic pattern are detected from a distortion detecting image obtained by the TV camera (S4). An ideal reference point predicted based on a standard pattern is set while correlated with the each reference point as a position of the reference point when the distortion is not generated (S8), and a displacement from the each reference point to the ideal reference point correlated with the reference point is found as a correction vector (S9, S10). A correction vector of the each pixel is found by carrying out interpolation using the correction vectors of the four reference points positioned in the periphery, as to all the pixels in the distortion detecting image (S12-S15). The correction vectors are applied to the image picked up by the TV camera to correct the distortion of the image. COPYRIGHT: (C)2008,JPO&INPIT