Digitization method and device for rainfall record drawings

Abstract

The invention discloses a digitization method of rainfall recording paper. The method comprises a step of extracting a binary grid image and a rainfall line image from the digital images of the rainfall recording paper, a step of correcting the binary grid image and the rainfall line image, a step of using a method of row projection to determine the boundary of a grid area from the grid image which is subjected to tilt correction and setting the area outside the boundary in the grid image and the rainfall line image which are subjected to tilt correction as a binarization background, a step of allowing the rainfall line image to be corresponding to the grid image, calculating each peak point in a rainfall line and the maximum value point of a rightmost peak point right side extension line, and finally summing the rainfall values corresponding to the above points to obtain rainfall. The invention also discloses a digitization device of rainfall recording paper. The recorded rainfall data can be rapidly, accurately and automatically extracted from the rainfall recording paper images, and convenience is brought to subsequent data query analysis.

Description

technical field [0001] The invention relates to a method and a device for digitalizing rainfall record drawings, which use a computer to automatically identify rainfall data recorded in the rainfall record drawings, and belong to the intersecting technical fields of hydrometeorology, digital image processing, image recognition and databases. Background technique [0002] Before the popularity of computers, in the fields of water conservancy, meteorology, biomedicine, petroleum geology, etc., the effective data information observed was drawn on paper engineering drawings through specific instruments or manually. The data on these paper hydrological data are relatively precious historical data, recording flow, water level, precipitation, evaporation, etc. Many of the data will be often used for further analysis and processing, and the use and sharing of these effective information It will provide scientific theory and basis for the construction of water conservancy projects in...

AI Technical Summary

Problems solved by technology

For rainfall recording paper, there are the following characteristics: Since the 24-hour rainfall process needs to be recorded, the width of the recording paper is relatively large, and the image captured by the camera has many pixels, which is prone to uneven illumination, which is manifested in different parts of the same curve The colors are inconsistent; due to the complexity of the rainfall process, the peaks are relatively dense during continuous torrential rain, which is manifested in the steep drop and rise of the rainfall line; and because the rainfall information of multiple days is recorded on a piece of paper, the recording lines may be parallel to each other or May be interlaced, traditional image processing methods are not easy to track and analyze the process changes of each line

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