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Evaluation of Differential Methods for Image Velocity Measurement

For eight point-based differential methods of image velocity measurement, including two new methods, quantitative evaluations are reported based on synthetic images, and qualitative evaluations based on real images.  A new method  (cluster method) is characterized by the determination of the nearest point to all constraint lines, and the other (VF expansion method) by local approximation of the motion vector field. For six methods, solutions for algorithmic use are compiled, e.g. also iterative solutions for the Schunck and the Nagel constraint. The given quantitative evaluations may be used for characterizing situations where methods may be applied, and where not, and what parameters may be suggested.