River water level visual measurement method without water gauge

Abstract

The invention discloses a river water level visual measurement method without a water gauge. The method comprises the following steps: shooting an image of a complete section of a river by using a camera with calibrated internal and external parameters, and performing nonlinear distortion correction; selecting a waterline area on the measurement section in the corrected image, wherein the size of the waterline area covers the amplitude of the water level; carrying out image segmentation on the selected waterline region by adopting a PSPnet network based on deep learning to obtain a binary image with a river bank as a foreground and a water surface as a background; carrying out horizontal projection on the binary image and searching a maximum gradient value to obtain an observation value of a longitudinal coordinate of a waterline image point; calculating a water line image point ordinate based on a variable-height water surface photogrammetry model iteration water level value, and taking the condition that the difference between the ordinate and the observation value is smaller than the measurement precision as an iteration stop condition to obtain a water level approximate value. Only the flow section terrain needs to be measured, a water gauge and a marker do not need to be installed, and the method has the advantages of being easy to arrange, high in damage resistance and visual in result.

Description

technical field [0001] The invention belongs to the technical field of water surface monitoring, and relates to an image-based water level monitoring technology, in particular to a water gauge-free visual measurement method for river water levels. Background technique [0002] Water level is not only an important parameter of the water body conditions of rivers, lakes and reservoirs, but also an important basis for water resource allocation and water conservancy project operation. In addition, water supply conditions, heavy rain conditions, flood disaster conditions, runoff information, sediment content, and nutrient transfer rates in cities and irrigation areas Such information usually needs to be calculated based on the measured water level. With the development of the smart water conservancy industry, more and more automatic water level detection equipment has appeared. Among them, the water level visual measurement technology has become an important part of the current wa...

AI Technical Summary

Problems solved by technology

[0008] In summary, the detection accuracy of the water edge during the measurement process is an important factor affecting the accuracy of the actual water level conversion. However, the existing water level visual measurement methods without water gauges have unique applicable conditions. Due to the limitations of their respective conditions, it is difficult to guarantee the measurement accuracy. Effect

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