Image-based motion measurement: new technology, new applications

High-speed photography has been used to make kinematic measurements for more than 120 years, but only in the last twenty-five years have significant advances been made in data capture techniques. In the 1970's, generalized photogrammetric methods for reconstructing two- and three-dimensional trajectories were devised, but in practice, few investigators could find the time to manually extract coordinate data from hundreds, if not thousands, of images. The 1980's saw the introduction of consumer vide and desktop computing, and the shift to electronic imaging began. New hardware, and more sophisticated software, made it possible to exploit the potential of an old technology. By the mid 1980's, investigators could extract coordinate data from a video signal, store the data in a workstation, and reconstruct 3D trajectories soon after a test has been conducted. 4D VIDEO was formed in October 1988. We have found that there is depth and breadth to the potential users of image-based motion measurement. However, few end-users are interested in the procedures required to capture and manipulate the coordinate data. Further, we have found that the sophisticated procedures required to extract kinematic data from images have become a burden in their own right. Techniques are required that minimize the effort of the end-user and provide results quickly and efficiently.