Visual measurement and three-dimensional reconstruction method of model terrain in muddy water

Abstract

The invention provides a visual measurement and three-dimensional reconstruction method of a model terrain in muddy water. According to the method, firstly, a video image file of the underwater model terrain is directly obtained by using a B-ultrasound instrument, and a single frame of B-ultrasound image is analyzed; then, according to the gray level and gradient features (a breakdown process exists) of terrain bright bands in the B-ultrasound image and the continuity of the model terrain in the horizontal direction, single-pixel extraction of a terrain boundary line in the single frame of the image is achieved at a time; according to the similarity of terrain lines in multiple frames of continuous images, cubic spline function interpolation is conducted, and underwater three-dimensional terrain is reconstructed. The visual measurement and three-dimensional reconstruction method is good in penetrability, high in adaptivity, suitable for underwater model terrain such as plastic sand, natural sand, pulverized coal ash and bakelite powder, high in operation speed, high in measurement accuracy, visual, efficient, rapid and capable of effectively eliminating imaging disturbance of unrelated moving suspended particles in water and reappearing underwater original terrain appearance; the single operation time is shorter than 0.1 second, and underwater terrain errors are all less than 1 millimeter after single measurement and reconstruction.

Description

technical field [0001] The patent of the invention belongs to the technical field of hydraulic model topography measurement, and in particular relates to a visual measurement and three-dimensional reconstruction method of model topography in muddy water. Background technique [0002] The river engineering model experiment is an important means for people to understand and study the river water and sediment movement, evolution and flood evolution law. In model tests, the real-time observation and analysis of underwater topography is of great significance to the study of river siltation and water erosion. In order to accurately obtain information such as underwater topography and its erosion and deposition changes in model tests, it is necessary to find a device for real-time dynamic observation and analysis of underwater topography information. In recent years, a variety of measuring instruments have been developed at home and abroad to measure the terrain of river engineeri...

AI Technical Summary

Problems solved by technology

In recent years, a variety of measuring instruments have been developed at home and abroad to measure the terrain of river engineering models, such as photoelectric reflection topographs, resistive topographs, tracking topographs, ultrasonic topographs, laser scanners and other instruments. At present, these terrain Most of the instruments are point-based measurements, which cannot realize non-contact multi-point online real-time image measurement and 3D reconstruction analysis of underwater model terrain, especially for underwater model terrain in the case of turbid water flow in moving bed model tests

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