The Improvement On The Particle Size Measurement System Based On Digital Image Process

There is exigent demand that machining of grains is asked not to stop while those grains being measured and that control should be feed back the machining equipment in real time in some enterprises. This thesis emphasizes only on resolving application development of measurement system on line to machining of industrial grains. The thesis brings forward using computer image measurement technology to acquire and process and analyse image of industrial grains in real time. Traditional handcrafted manner will be replaced by this system. The system will make operator's working intensity descend and enhance efficiency of measurement and analysis, moreover, output corresponding analysis data and curves and images and diagram according to user's need.This thesis is an improvement on the former measurement system. The basis of image recognition is grey image originally. Namely, 24 bits natural color image coming from image acquisition is transformed into 256-color bit map, then grey image. By filtering, sharpening, grayness revision and threshold, the objects can be segmented out of the background at last. In this thesis, in view of the special condition of measuring coal powder particle, the realization of image recognition is not on the basis of gray image, but under the mode of RGB, deriving from the change of the quantity of one's own RGB of each point. In the development of the software system, Microsoft Visual C++ 7.1 has become the first-selected compiler in our project for its high compatibility with the standard C/C++99. Through the measurement system based on the principles of image measurement, which includes image acquisition card based on PCI bus, CCD pickup camera, computer, etc, the realization of image acquisition and image display is achieved. This thesis adopted single scanning algorithm which is of constant. Because the measurement time is transient, this kind of method is very suitable for high speed measurement on line. At last, we bring this measurement system into the whole control system. From the view of distributed control and predictive control, we have a further discussion about this project, and open up a wider field for the research in the future.