Measurement Of Rainfall Intensity Based On Raindrop Spectrum

Precipitation is an important object to study the global hydrothermal circulation and climate change. The traditional raindrop spectrum data mainly rely on artificial analysis, this processing process is cumbersome, and vulnerable to the influence of environmental and human factors, resulting in can not accurately detect the rainfall data.In this paper, the problem of precipitation is measured by image acquisition method is studied. It is proposed to measure the rainfall intensity by combining the camera to collect the raindrop spectrum image and the digital image processing technology. Study on raindrop particle segmentation algorithm in the case of adhesion. A method based on convex hull for detecting the concave point of adhesion raindrop particles is proposed. According to the shape model of raindrop particles in different diameters. The measurement of rainfall intensity based on different raindrops is presented. The observed raindrops were analyzed by the method of sorting and averaging based on two parameters (the Method of Sorting and Averaging based on Two Parameters, abbreviated SATP method), and the rainfall intensity was calculated from the parameters in the SATP method. Specific research is as follows:The image preprocessing technique is analyzed. The method of bilateral filtering is used to denoise the image of the raindrop spectrum and improve the sharpness of the image. For the shooting image background background uneven phenomenon, the top hat transform technique is used to enhance the image contrast.Segmentation of raindrops is achieved by using Otsu(OSTU) threshold segmentation algorithm.According to the variation characteristics of the angle of the pits in the overlap.An algorithm based on convex hull for the detection of the concave point of adhesion raindrop particles is proposed. The concave points of the search particles are transformed into the convex points of the concave area by extracting the depressed regions of the adhered particles. Using the local variation characteristics of the angle of the depression area. Determine the bumps in the raindrops to achieve the sticky raindrops, and improve the accuracy of rainfall intensity measurement.According to the rain of particles with different diameters in the shape differences. The measurement of rainfall intensity based on different raindrops shapes is proposed. Using the relationship between the collected image and the actual object size. The actual raindrop particle diameter value is obtained. To achieve the size of the rain diameter conversion. The observed raindrops were analyzed by the method of Sorting and Averaging based on Two Parameters,so as to determine the rainfall intensity value.Experiments show that the method of measuring the rainfall intensity value by the combination of camera acquisition and image processing is effective in the rain environment. The values are compared with the measured values of the rain gauge,and the data are basically the same.