A shallow stratum profile data three-dimensional image real-time display method

Abstract

The application discloses a shallow stratum profile data three-dimensional image real-time display method, which comprises the following steps: emitting an acoustic wave signal to a target to be measured, collecting an echo signal of the acoustic wave signal reflected by the target to be measured to obtain a single frame, performing signal processing on the echo signal to obtain shallow stratum profile data, performing beam mapping on the shallow stratum profile data, mapping the shallow stratum profile data into a three-dimensional coordinate system to obtain drawing data of a three-dimensional acquisition image, and then updating the three-dimensional acquisition image under a current frame in real time. The shallow stratum profile equipment based on the transmitting phased array principle can quickly collect the shallow stratum profile data of a region through continuous scanning at different angles, and can form a three-dimensional seabed image of a current measurement area in real time, so that a measurer can evaluate the current measurement area. The measurement efficiency of the application is higher than that of a conventional shallow stratum profile equipment, and the application can measure stratum data that cannot be measured by a multi-beam sounding equipment and a side scan equipment.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of underwater detection, and particularly relates to a shallow stratigraphic profile data three-dimensional image real-time display method. BACKGROUND

[0002] International deep-sea high-tech development is changing rapidly, and seafloor topography and bottom exploration is the basis for marine environmental investigation, marine engineering design and resource development.

[0003] In underwater acoustic measurement, multi-beam sounding sonar and side scan sonar equipment can only measure the seafloor topography, while shallow stratigraphic profile sonar can not only measure the seafloor, but also collect data within several meters to several hundred meters below the seafloor, which can be used for marine engineering survey, marine resource investigation, and detection of seafloor bottom and buried targets.

[0004] Multi-beam sounding system, side scan system and shallow stratigraphic profiler equipment are essential acoustic detection equipment in modern marine foundation survey, and their main functions are to detect seafloor topography and bottom stratification. However, multi-beam sounding equipment and side scan equipment can only obtain three-dimensional results of seafloor topography. Conventional shallow stratigraphic profile equipment can only form two-dimensional image results. If the measured data needs to be converted from two-dimensional data to three-dimensional data, the shallow stratigraphic profile equipment needs to be densely arranged in the area to collect a large amount of two-dimensional data, and the effective three-dimensional data results in the area can be formed by stacking these data. This three-dimensional image result needs the stacking of two-dimensional data, so the three-dimensional imaging work is usually completed in the office, and cannot be generated in real time. SUMMARY

[0005] The technical purpose of the present application is to provide a shallow stratigraphic profile data three-dimensional image real-time display method to solve the problems of limited collection and low collection efficiency.

[0006] To solve the above problems, the technical scheme of the present application is as follows:

[0007] A shallow stratigraphic profile data three-dimensional image real-time display method, comprising the following steps:

[0008] Emitting a sound wave signal to the target to be measured, and collecting the sound wave signal reflected by the target to be measured to obtain a single frame of echo signal;

[0009] Performing signal processing on the echo signal to obtain shallow stratigraphic profile data, and performing beam mapping on the shallow stratigraphic profile data to map it into a three-dimensional coordinate system to obtain drawing data of a three-dimensional collection image, and then updating the three-dimensional collection image in real time under the current frame;

[0010] The drawing data includes a coordinate array and a color array.

[0011] Further preferably, before emitting the sound wave signal to the target to be measured, the emitting direction is deflected according to the current attitude of the shallow ground profiler and the expected measuring angle, and then the sound wave signal is emitted to the target to be measured.

[0012] The echo signal is filtered and sampled.

[0013] Specifically, the three-dimensional coordinate system is XYZ, wherein the Y direction represents the depth direction, the X direction represents the north-south direction of the latitude and longitude coordinate projected into the XOZ plane rectangular coordinate system, and the Z direction represents the east-west direction of the latitude and longitude coordinate projected into the XOZ plane rectangular coordinate system.

[0014] Further preferably, before performing the beam mapping, the sound speed correction is performed to correct the measured depth in the Y direction.

[0015] The specific steps of performing the beam mapping are as follows:

[0016] The GPS coordinate mapping is performed to correspond the shallow ground profile data of each frame to the corresponding GPS coordinate information, project the GPS coordinate information into the XOZ plane rectangular coordinate system, and further obtain the X and Z coordinate information of the shallow ground profile data of each frame in the three-dimensional coordinate system.

[0017] The beam diffusion mapping is performed to expand the echo signal into a spatial beam shape according to the shallow ground profile data, and obtain the corresponding coordinate array in the three-dimensional coordinate system XYZ in combination with the GPS coordinate information.

[0018] Further preferably, the color mapping is further included, which is specifically converting the signal strength of the shallow ground profile data into values in the range of 0-255 by equal ratio conversion, and then converting the values of 0-255 in the data into corresponding colors in the color library to further obtain the color array.

[0019] Supposing that the maximum value of the shallow ground profile data converted by equal ratio conversion is and the minimum value is the conversion formula for converting into the corresponding colors in the color library is:

[0020]

[0021] wherein, is the color step in the color library, and is the value to be currently calculated.

[0022] The present application has the following advantages and positive effects compared with the prior art due to the above technical solutions:

[0023] This invention relates to a shallow seismic profiling device based on the principle of phased array transmission. Through continuous scanning of the seabed at different angles, it rapidly acquires shallow seismic profile data of a region and generates a three-dimensional seabed image of the current measurement area in real time. This provides detailed and effective data results for marine engineering exploration and marine resource surveys in a real-time and efficient manner, facilitating surveyors' assessment of the current measurement area and providing a basis for subsequent measurement work and related engineering projects.

[0024] This invention relates to a shallow seismic profiling device based on the principle of phased array scanning. A single flight can obtain stratigraphic structure results within a region through scanning measurements, while simultaneously generating 3D images in real time, ultimately creating a 3D image display of the area. Its measurement efficiency is higher than conventional shallow seismic profiling devices, and it can measure stratigraphic data that multibeam echo sounders and side-scan devices cannot obtain. Attached Figure Description

[0025] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention.

[0026] Figure 1 This is a flowchart of a method for real-time display of three-dimensional images of shallow seismic profile data according to the present invention;

[0027] Figure 2 This is a schematic diagram of a two-dimensional waterfall after mapping the shallow seismic profile data of the present invention. Detailed Implementation

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings and other implementation methods can be obtained based on these drawings without any creative effort.

[0029] To keep the drawings concise, only the parts relevant to the invention are shown schematically in each figure, and they do not represent the actual structure of the product. Furthermore, for ease of understanding, in some figures, only one of components with the same structure or function is shown schematically, or only one is labeled. In this document, "one" can mean not only "only one" but also "more than one".

[0030] The following detailed description, in conjunction with the accompanying drawings and specific embodiments, provides a method for real-time display of three-dimensional images of shallow seismic profile data according to the present invention. The advantages and features of the present invention will become clearer from the following description and claims.

[0031] Example

[0032] See Figure 1 This embodiment provides a method for real-time display of three-dimensional images of shallow seismic profile data. Firstly, the first step in implementing this embodiment is to determine the current attitude of the shallow seismic profiler and the desired measurement...

[0033] Angle measurement is used to deflect the emission direction. This ensures accurate detection of the target at the desired location, which can be a buried object, pipeline, or substrate. A sound wave signal is then emitted towards the target, and the echo signal reflected from the target is collected to obtain each single frame.

[0034] Then, signal processing is performed on the echo signal to obtain shallow seismic profile data. To ensure signal quality and image display efficiency, the echo signal needs to be filtered and sampled.

[0035] Next, beam mapping is performed on the shallow seismic profile data to map it into a three-dimensional coordinate system. This system consists of X, Y, and Z coordinates, where the Y direction represents the depth, the X direction represents the north-south direction projected onto the XOZ plane rectangular coordinate system, and the Z direction represents the east-west direction projected onto the XOZ plane rectangular coordinate system. This yields the plotting data for the three-dimensional acquired image, which includes coordinate and color arrays, and is used to update the three-dimensional acquired image in real time for the current frame.

[0036] Preferably, sound velocity correction is required before beam mapping to correct the measurement depth in the Y direction. This can be done using the surface sound velocity or sound velocity profile measured by the onboard sound velocity meter. Due to the influence of temperature, salinity, and pressure, the speed of sound propagation varies at different depths in the ocean. According to the principle of acoustic ranging, different sound velocities will lead to different ranging results. Therefore, to obtain more accurate measurement results, sound velocity correction is needed, which is essentially a depth correction of the measurement results, i.e., the measurement depth in the Y direction.

[0037] Then, the specific steps for performing beam mapping are as follows:

[0038] GPS coordinate mapping is performed to correlate each frame of shallow seismic profile data with its corresponding GPS coordinate information. Since the shallow seismic profiler is a device mounted on a survey vessel for on-the-go surveying—that is, measuring shallow seismic profile data while the vessel is in motion—when creating the 3D map, we need to obtain the corresponding GPS coordinate position via the GPS measuring instrument each time an echo signal is received. Only by combining the GPS coordinate information with the shallow seismic profile data can we obtain complete and accurate measurement results. After obtaining the GPS coordinate information, it is projected onto the XOZ plane rectangular coordinate system, thus obtaining the X and Z coordinate information of each frame of shallow seismic profile data in the 3D coordinate system.

[0039] Then, the beam spread mapping is performed. Since the shallow stratum profile data is commonly mapped in the way of two-dimensional waterfall chart, as shown in Figure 2 , and the acoustic wave signal is emitted from the acoustic sensor, the beam opening angle becomes larger and larger with the increase of the walking path. Therefore, the echo signal is spread into the spatial beam shape according to the shallow stratum profile data, and the beam solid shape of each received signal can be calculated according to the acoustic correlation theory. After the calculation, the coordinate array of the shallow stratum profile data in three directions of the three-dimensional coordinate system XYZ is obtained in combination with the GPS coordinate information.

[0040] Preferably, referring to Figure 1 and Figure 2 , the color mapping is also included in the present embodiment to realize the visualization of different colors of the obtained three-dimensional model. As shown in Figure 2 , the horizontal axis in Figure 2 is the beam count, the vertical axis is the depth, and the intensity of the echo signal is mapped by the color. That is, the rightmost side is the depth scale, the left color gradient vertical bar is the color map (colormap), and the middle is the two-dimensional waterfall chart display. The white at the top of the colormap corresponds to the minimum echo energy, the red at the bottom of the colormap corresponds to the maximum echo energy, the color gradient has 0~255 levels, and each color corresponds to an energy level. We convert the signal intensity of the shallow stratum profile data into a value in the range of 0~255 in proportion, that is, 256 energy levels, and then convert the value of 0~255 in the data into the corresponding color in the color map, thereby obtaining the color array, that is, the color corresponding to each point of the three-dimensional model. In order to ensure the image display effect, any color map in the color map library can be selected for mapping, or a desired color map can be defined according to the existing color map. Selecting a suitable colormap can help the image to achieve better color mapping effect, such as clearer stratum and more clear target.

[0041] wherein, assuming that the maximum value of the shallow stratum profile data converted in proportion is , and the minimum value is , the conversion formula for converting into the corresponding color in the color map is:

[0042]

[0043] wherein, is the color level in the color map, is the value currently to be calculated.

[0044] Finally, the drawing data in the video card memory is updated, and the image display is refreshed to display the three-dimensional model.

[0045] The image display is refreshed. Updating the drawing data in the video card memory can refresh the image display

[0046] The embodiments of the present application are explained in detail above with reference to the drawings, but the present application is not limited to the above-described embodiments. Even if various changes are made to the present application, if the changes fall within the scope of the claims of the present application and equivalents thereof, they are still within the protective scope of the present application.

Claims

1. A method of real-time display of a three-dimensional image of shallow subsurface profile data, characterized by, The method comprises the following steps: emitting an acoustic wave signal to a target to be measured, and collecting an echo signal reflected by the target to be measured to obtain a single frame of the echo signal; processing the echo signal to obtain shallow stratum profile data, performing beam mapping on the shallow stratum profile data, mapping the data into a three-dimensional coordinate system, obtaining drawing data of a three-dimensional acquisition image, and updating the three-dimensional acquisition image in real time under the current frame; wherein the drawing data comprises a coordinate array and a color array; wherein the three-dimensional coordinate system is XYZ, wherein Y represents the depth direction, X represents the north-south direction in the XOZ plane rectangular coordinate system, and Z represents the east-west direction in the XOZ plane rectangular coordinate system; wherein the specific steps of performing beam mapping are: performing GPS coordinate mapping, corresponding the shallow stratum profile data of each frame to the corresponding GPS coordinate information, projecting the GPS coordinate information into the XOZ plane rectangular coordinate system, and obtaining the X and Z coordinate information of the shallow stratum profile data of each frame in the three-dimensional coordinate system; performing beam diffusion mapping, extending the echo signal into a spatial beam shape according to the shallow stratum profile data, and combining the GPS coordinate information to obtain the coordinate array corresponding to the three directions XYZ of the three-dimensional coordinate system.

2. The real-time display method of the three-dimensional image of the shallow stratum profile data according to claim 1, characterized by, Before emitting the acoustic wave signal to the target to be measured, the emission direction needs to be deflected according to the current shallow stratum profiler attitude and the expected measurement angle.

3. The real-time display method of the three-dimensional image of the shallow stratum profile data according to claim 1, characterized by, The collected echo signal needs to be filtered and sampled.

4. The real-time display method of the three-dimensional image of the shallow stratum profile data according to claim 1, characterized by, Before performing beam mapping, the sound velocity needs to be corrected to correct the measurement depth in the Y direction.

5. The real-time display method of the three-dimensional image of the shallow stratum profile data according to claim 1, characterized by, Before performing beam mapping, color mapping is also included, which is specifically converting the signal intensity of the shallow stratum profile data into a value in the range of 0-255 by equal ratio conversion, and then converting the value of 0-255 in the data into the corresponding color in the color chart library to obtain the color array.

6. The real-time display method of the three-dimensional image of the shallow stratum profile data according to claim 5, characterized by, Assuming the maximum value of the converted shallow stratigraphic profile data is and the minimum value is The conversion formula for converting into the corresponding color in the color chart library is: wherein is the color step in the color gallery, is the value currently to be calculated.

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