Research On Movement Recognition And Tracking Of Sediment Particles Based On Digital Image Processing Technology

The law of bed movement is one of the core issues in river dynamics research,and it is also the key to solving the practical problems of many water conservancy projects.In recent years,with the continuous advancement of computer technology and the rapid development of digital image processing technology,digital image technology has been widely used in various fields.Digital image processing technology has gradually become an important technical means in the experimental study based on the mass transfer model to deeply analyze the movement law of the bed sediment.In the process of the tank test,the movement trajectory of the absorbing sediment particles was obtained by a high-speed camera,and the basic motion parameters of the sediment particles were obtained by digital image processing technology and the characteristics of the movement characteristics of the granules were further analyzed.The research is located in the experimental hall of the sedimentation station of the sedimentation site of the Daxing Experimental Base of the ChinaInstitute of Water Resources and Hydropower Research.The sediment transport experiment of the sediment is carried out in a straight glass water tank.Aiming at the existing experimental conditions,a method for identifying and tracking the sediment particles in the complex background is proposed.Firstly,the high-speed camera is used to collect the moving image of the absorbing sediment particles at high spatial and temporal resolution,and then through the image processing and statistical analysis,the basic motion parameters such as the trajectory of the sediment particles,the number of moving particles,the movement time and the moving distance are extracted.In-depth study of the characteristics of the mass movement at the particle scale.The main results achieved in this paper:(1)According to the water tank test of moving sediment particles from the top,this paper adopts an image acquisition system adapted to the test conditions,including: IDT high-speed camera,related software computer terminal,LED illumination system,vertical to the bed surface.A height-adjustable high-transmission glass pressure wave plate and other components.The test results show that the test device can effectively avoid the problem of unable to clearly capture the moving sediment particles due to the fluctuation of the water surface in the water tank,and improve the illumination conditions of the high-speed camera,which provides a very clear movement for the sediment particles.Great help.(2)In the experimental study of the movement of sedimentary sedimentparticles,the traditional particle identification and tracking method has a relatively large error under complex background conditions.In this paper,digital image processing technology is used to complete the image pre-processing of the original image,and then the image subtraction method is used to subtract the image to obtain the gray-scale difference image,and then the image is converted into binary image.Furthermore,the morphological algorithm(corrosion,expansion)in matlab software is used to obtain the position of the particle motion by binary image processing,and the centroid position of the moving particle is determined.The particle motion trajectory is obtained by calculating the gray correlation coefficient of the two frames.(3)Using the IDT high-speed camera to shoot the movement of sediment particles,select 8s of the video data and convert it into 200 frames.The moving sediment particles were identified and tracked,and the moving particles were obtained for identification.63 positional coordinates of nearly 5,000 sediment particles were obtained.The movement characteristics of the bedload sediment particles were analyzed by using the obtained basic motion parameter data.(4)There is obvious intermittentity in the movement of sediment particles in the process of water flow.During the movement process,the sediment particles often have cyclical motion states such as motion-stationary-re-motion,and accurately obtain the movement distance and motion of the particles.Time and speed of motion,etc.,and then analyze the law of particle motion.