Research On The Software And Processing Method Of Underwater Cold Spring Acoustic Image System

Since that natural gas hydrate can be obtained from seabed cold seep,its exploration is of great importance for alleviating energy crisis and environment deterioration.Specifically,seabed cold seep acoustic image systems is used to enhance the display performance of the acoustic image of the cold seep,and hence is helpful to the exploration of the cold seep.This thesis focus on the design for the detection system software based on LabVIEW,methods of acoustic image processing and cold seep 3D reconsturction.The main work includes:(1)Based on Lab VIEW,a real-time display module for seafloor depth,a real-time display module for measuring speed and altitude as well as a real-time display module for posture of measuring ship are designed and implemented.The tests using the playback function and the sea trial data show that the real-time display module of the seabed is working normally.The debugging of the virtual serial port,the serial port debugging software and the communication protocol between GPS,the posture sensor and the detection system shows that other modules are also working normally.(2)To deal with the blur problem of seabed cold seep acoustic image due to the noise of marine environment and the body noise of measuring ship,a new method of acoustic image combination denoising is proposed based on the traditional airspace wiener filter and median filter method,and is applied to the detection system software based on Lab VIEW.The test results show that the denoising performance of the new method is improved compared with the traditional method.(3)To deal with the low contrast of the cold seep target in the acoustic image of the seabed cold seep due to acoustic "soft interface" of cold seep bubble,a new acoustic image combination enhancement method is proposed based on the traditional histogram equalization and discrete space difference method,and is applied to the LabVIEW-based detection system software.The test results show that the enhancement performance of the new method is improved compared with the traditional method.(4)To deal with the problem of the cold seep 3D model reconstruction,the sample space of acoustic image data is interpolated to obtain the grid data by multiple interpolation methods,then using Marching Cubes algorithm to reconstruct the cold seep 3D model.The simulation results show that the nearest neighbor interpolation method has the better interpolation effect.