Accurate Feature Extraction and Control Point Correction for Camera Calibration with a Mono-Plane Target

The paper addresses two problems related to 3D camera calibration using a single mono-plane calibration target with circular control marks. The first problem is how to compute accurately the locations of the features (ellipses) in images of the target. Since the structure of the control marks is known beforehand, we propose to use a shape-specific searching technique to find the optimal locations of the features. Our experiments have shown this technique generates more accurate feature locations than the state-of-the-art ellipse extraction methods. The second problem is how to refine the control mark locations with unknown manufacturing errors. We demonstrate in a case study, where the control marks are laser printed on a A4 paper, that the manufacturing errors of the control marks can be compensated to a good extent so that the remaining calibration errors are reduced significantly. 1

The Healthy Farms, Food and Communities Act: Policy Initiatives for the 2002 Farm Bill And the First Decade of the 21st Century

This policy document includes a legislative initiative to be incorporated into the 2002 Farm Bill, and a broader set of policy principles and legislation endorsed by CFSC. Both policy platforms create the basis for furthering the goals of healthy farms, healthy food, and, ultimately, healthy communities