<title>New measuring concepts using integrated online analysis of color and monochrome digital high-speed camera sequences</title>

Abstract

High speed sequences allow a subjective assessment of very fast processes and serve as an important basis for the quantitative analysis of movements. Computer systems help to acquire, handle, display and store digital image sequences as well as to perform measurement tasks automatically. High speed cameras have been used since several years for safety tests, material testing or production optimization. To get the very high speed of 1000 or more images per second, three have been used mainly 16 mm film cameras, which could provide an excellent image resolution and the required time resolution. But up to now, most results have been only judged by viewing. For some special applications like safety tests using crash or high-g sled tests in the automobile industry there have been used image analyzing techniques to measure also the characteristic of moving objects inside images. High speed films, shot during the short impact, allow judgement of the dynamic scene. Additionally they serve as an important basis for the quantitative analysis of the very fast movements. Thus exact values of the velocity and acceleration, the dummies or vehicles are exposed to, can be derived. For analysis of the sequences the positions of signalized points--mostly markers, which are fixed by the test engineers before a test--have to be measured frame by frame. The trajectories show the temporal sequence of the test objects and are the base for calibrated diagrams of distance, velocity and acceleration. Today there are replaced more and more 16 mm film cameras by electronic high speed cameras. The development of high-speed recording systems is very far advanced and the prices of these systems are more and more comparable to those of traditional film cameras. Also the resolution has been increased very greatly. The new cameras are `crashproof' and can be used for similar tasks as the 16 mm film cameras at similar sizes. High speed video cameras now offer an easy setup and direct access to digital image data. An integrated software solution (MOTION HRC ImageServer) for interfacing the camera will be presented: it controls the recording and the transfer of the images to a PC and contains tools for sequence processing, display, storage and database handling. A corresponding viewing software enables a comfortable visualization of film sequences from standard desktop pc's, replacing the presentation of 16 mm films or video tapes. The new analysis software MOTION LC was designed in cooperation with the automotive industry specially for the use with high speed video cameras. It automizes all necessary steps to measure the positions of signalled points within an image sequence and to derive calibrated trajectories. These tools now allow new integrated analyzing concept, with a very fast processing time starting with the test up to the print out of result diagrams. The system supports a lot of image sources and shows an open interface for data in- and output.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.