Research On The Image Processing In Real-Time Measurement Technique

Image is the carrier of information in structured-light three-dimensional profile measuring system. According to the theory of optical triangulation, the image of object is studied by digital image technique, then the model of vision measurement is built, and the quantitative dimension and shape of practical objects can be achieved.In the purpose of achieving real-time three-dimensional measurement, the key technique of structured-light mearsurement techniques has been reseached at the base of the relation research effort. Mainly inclouding:(1) The base theory of numerical image and the key algorithms of image processing are introduced firstly. Such as image enhanced, image splited and image smoothing.(2) Research on the image processing algorithms of geometric paramenter in vision detection, such as circle and ellipse approaching, getting the center of circle, crossing auto-detected and line auto-detection, etc.(3) Combining with the characters of laser stripe, the thining method has been studied for extracting the light strip. According to the laser beam obeys Gauss distribution, the light stripe is parted using Minimum Enclosing Rectangle, the centric of light stripe is gotten by the method of Gaussian curve approximation in every rectangle region, the light stripe line is fit by least square method. The light strip center is located at sub-pixel and the precision of the measurement is increased.(4) The math model and the hardware structure of the Structrued light 3-D profile measurement system are introduced, and the methods and the steps of calibration for camera are domonstrated.(5) The development of image processing soft based on VC++6.0, building the open base standard function storeroom for vision measurement, The experiment results of criterion measuring shows the Structured-light three-dimensional profile measuring techniques put forwarded in this paper is practical and suitable for on-line detection.