KR100609004B1 - Method for recovering topography using digital photogrammetry technique - Google Patents

Abstract

The present invention relates to a method for restoring terrain using digital photogrammetry, and more specifically, (a) (i) photographing aerial photographs of target sites before and after development, and then generating aerial photographs by scanning films. Doing; (Ii) extracting three-dimensional ground control points (GCPs) of the target site using a total station; (Iii) performing an aerial triangulation that connects the three-dimensional spatial coordinates (GCP) and the same point of the aerial image using a digital photogrammetry system, and then forms a three-dimensional digital image space; (b) generating digital terrain model (DTM) data before and after development in the three-dimensional digital image space using the digital photogrammetry system; (c) generating grid data before and after development including an orthoimage map and three-dimensional topographical information based on the generated digital terrain model data; And (d) extracting cut and fill area and volume required for the restoration of the terrain by numerically comparing the DTM data and the grid data before and after the development. It relates to a method of restoring the terrain.

The terrain restoration method using the digital photogrammetry according to the present invention uses the extracted terrain information to check the cut and fill volume compared with the past terrain, and quantitatively calculates the quantity for the restoration of the terrain, indiscriminately due to difficult development. It can restore the damaged natural environment and ecosystem, and it will be effectively used to improve the quality of the national environment because it has the effect of suppressing the undeveloped development in the future.

Aerial photograph, before / after comparison, cut, fill, terrain restoration

Description

Terrain Restoration Method Using Digital Photogrammetry Techniques {Method for Recovering Topography Using Digital Photogrammetry Technique}

1 illustrates a method of generating a three-dimensional image space by using aerial photographing and digital photogrammetry before and after development.

2 is a flowchart illustrating a terrain restoration technique using a digital photogrammetry technique.

3 is a flowchart illustrating a process of extracting cut and fill location, area, and volume data required for topographic restoration using 3D terrain data before and after development.

Field of invention

The present invention relates to a method for restoring terrain using digital photogrammetry, and more specifically, (a) (i) photographing aerial photographs of target sites before and after development, and then generating aerial photographs by scanning films. Doing; (Ii) extracting three-dimensional spatial coordinates (GCP) of the object using a total station; (Iii) performing an aerial triangulation that connects the three-dimensional spatial coordinates (GCP) and the same point of the aerial image using a digital photogrammetry system, and then forms a three-dimensional digital image space; (b) generating digital terrain model (DTM) data before and after development in the three-dimensional digital image space using the digital photogrammetry system; (c) generating grid data before and after development including an orthoimage map and three-dimensional topographical information based on the generated digital terrain model data; And (d) extracting cut and fill area and volume required for the restoration of the terrain by numerically comparing the DTM data and the grid data before and after the development. It relates to a method of restoring the terrain.

Background of the Invention

The present invention is a method for restoring the terrain damaged by difficult development, such as road construction and earth excavation, the conventional restoration method to obtain aerial photographs and topographic maps before development, to establish a plan or to view the damaged terrain on the site and properly connect them Method has been used, and there have been no examples of quantitative restoration of the terrain in the past. In order to solve this problem, the aerial photogrammetry under consideration in the present invention was developed by Laussedat in 1851 and developed for over 150 years. Photogrammetry is now in the phase of digital photogrammetry from flat photogrammetry to analog photogrammetry and analytical photogrammetry. In digital photogrammetry systems, computers have replaced optical-mechanical components. Historically, analytical aerial survey results were analogue topographic maps, but nowadays they are digital products such as digital elevation models (DEMs) or digital maps. Digital photogrammetry is photogrammetry applied to numerical images that are stored and processed on a computer. Digital images are either scanned from photographs or acquired directly by a digital camera. Many photogrammetric tasks are automated to a high level by digital photogrammetry, such as automatic digital elevation model (DEM) data extraction and digital orthodontic image generation. The most important advantage of photogrammetry is that it reproduces the situation at the time of shooting completely visually through the three-dimensional image space.

Accordingly, the present inventors have made diligent efforts to solve the shortcomings of the prior art. As a result, the cut and fill locations and areas can be restored to extract near three-dimensional terrain data by using photographed aerial photographs before and after development. By confirming that the quantitative information of the volume is provided, the present invention has been completed.

The main object of the present invention is to provide a method for restoring a terrain using digital photogrammetry to restore near-circular shape using three-dimensional terrain data before and after development.

In order to achieve the above object, the present invention comprises the steps of (a) (a) photographing the aerial photograph of the subject before and after development, and then generating an aerial photograph by scanning the film; (Ii) extracting three-dimensional spatial coordinates (GCP) of the object using a total station; (Iii) performing an aerial triangulation that connects the three-dimensional spatial coordinates (GCP) and the same point of the aerial image using a digital photogrammetry system, and then forms a three-dimensional digital image space; (b) generating digital terrain model (DTM) data before and after development in the three-dimensional digital image space using the digital photogrammetry system; (c) generating grid data before and after development including an orthoimage map and three-dimensional topographical information based on the generated digital terrain model data; And (d) extracting cut and fill area and volume required for the restoration of the terrain by numerically comparing the DTM data and the grid data before and after the development. Provides a method of restoring the terrain.

In the present invention, the step (a) may be characterized in that at the time of aerial photography, by taking 60% or more overlapping photographs of adjacent photographs to have a common space of 60% or more in two adjacent photographs.

In the present invention, the step (d) converts the digital topography model (DTM) data before and after the development into a lattice shape, and performs a subtraction operation to contain cut amount (-) and fill amount (+) information. Create a grid-like data, (ii) multiply the number of (-) and (+) grids by the area occupied by one grid in real space, and obtain the cut (-) and fill (+) areas, and (-) And multiplying the number of (+) gratings by the area that one grating will occupy in real space, and then multiplying the values of the gratings representing cut and fill depths to obtain the volume to be cut (-) and the volume to be filled (+). can do.

Hereinafter, with reference to the accompanying drawings will be described in detail the present invention.

Terrain restoration method using digital photogrammetry according to the present invention is to obtain the aerial photo after the development through aerial photography to extract the three-dimensional terrain information, to obtain the aerial photo before development to extract the three-dimensional terrain information Comparing the three-dimensional topographical information before and after the development and development, it is composed of the steps of extracting the area and volume of cut and fill areas necessary for restoration.

1 illustrates a method of generating a three-dimensional image space by using aerial photographing and digital photogrammetry before and after development. The aerial photograph of the current region is used to construct a three-dimensional image space environment. In step S101, aerial images are taken of the same area in the past to construct a three-dimensional image space (S102). When explaining how to construct a three-dimensional image space, when the plane is taken while giving 60% or more redundancy to adjacent photographs, the two photos have more than 60% common space, which is called a model. (S103). Using the digital photogrammetry system, the three-dimensional image reflects the real world through the absolute stage of acquiring three-dimensional spatial coordinates using total stations and combining them with the image coordinates. A digital image space is formed (S104). Three-dimensional image space is realized through the process of combining the three-dimensional spatial coordinate surveying and image coordinate using the total station using the function of recognizing the space by the difference of the image shown in the left eye and right eye of the human do.

When photographing aerial photographs, most of the country's hard-to-development lands cannot acquire spatial information for restoration at all, so if you use aerial photographs constructed from aerial photography and DB since the late 1960s, national territory development will be carried out in earnest. It is possible to reproduce the homeland environment before it became a prototype.

2 is a flowchart illustrating a terrain restoration technique using a digital photogrammetry technique. After aerial photographing of a target area to be restored after development (S201), an aerial photograph image is generated by scanning a film (S202). During the field survey, a total station survey was performed to extract three-dimensional spatial coordinates (GCP) from the target site (S203), and three-dimensional spatial coordinates (GCP) and photographed aerial image using a digital photogrammetry system. When performing an aerial triangulation step connecting the same point in the photographic image (S204), a three-dimensional digital image space is formed in the numerical photogrammetry system, and the figure showing the current state after development in this space. Generate a Terrain Model (DTM) data (S205).

The extraction of the digital terrain model (DTM) data has an automatic extraction method and a manual extraction method. The automatic extraction method has the advantage of completing the work in a short time, and the manual extraction method increases the accuracy. There are advantages to this, but do not mix them.

Based on the digital terrain model (DTM) data, an orthoimage map showing a post-development image and a grid-shaped data including three-dimensional terrain information are generated (S206). Using the same method, three-dimensional digital image space of the target site must be implemented before development, which scans the aerial photographs before development and the target three-dimensional spatial coordinates (GCP) acquired by the total station. The three-dimensional digital image space at the time when the image of the past was taken through an aerial triangulation process is implemented (S207). In the implemented three-dimensional digital image space, the past three-dimensional terrain before the development is generated using digital extraction model (DTM) data and grid data format using automatic extraction and manual extraction (S208). Numerical 3D topographical information before and after development was numerically compared (D209) and cut and fill locations and areas (S210), cut and The volume of each fill location is obtained (S211), and finally, before and after development, the terrain is generated to be viewed by external workers using 3D fly simulation (S212).

3 is a flowchart illustrating a process of extracting cut and fill location, area, and volume data required for topographic restoration using 3D topographical data before and after development, and grids 3D topographical data before development. Grid (Cut and Fill Raster Data) that contains cut and fill volume information by converting to a form (S301) and converting the three-dimensional terrain after development into a lattice (S302), and then performing a subtraction (-) operation (S303). To generate (S304). Among the grid data, the grid containing the negative value is a space (S305) that requires cutting, and the grid containing the positive value is a space (S306) that requires a fill. To find the area and volume of cut space, multiply the number of (-) grids by the area occupied by one grid in real space (S307) to obtain the cut area, and the number of (-) grids by one grid in real space After multiplying the area by multiplying the value of the lattice representing the depth to be cut (S308) to obtain a volume to cut. In the same way, to find the area and volume of fill space, the number of (+) grids is multiplied by the area occupied by one grid in real space (S309) to obtain the fill area, and the number of (+) grids is one grid. After multiplying the area occupied by the real space and multiplying the value of the grid representing the depth to be filled (S310) to extract the volume to be filled, the extracted fill and cut area and volume is reflected in the terrain restoration.

Having described the specific parts of the present invention in detail, it will be apparent to those skilled in the art that such specific descriptions are merely preferred embodiments, and thus the scope of the present invention is not limited thereto. will be. Thus, the substantial scope of the present invention will be defined by the appended claims and their equivalents.

As described in detail above, the present invention is to restore the modified terrain and natural environment due to indiscriminate development, by extracting the three-dimensional terrain and environment using the photographed aerial photo before and after development, close to the original It is effective to provide topographical restoration method using digital photogrammetry that provides quantitative information of cut, fill location, area and volume for restoration. Terrain restoration method using digital photogrammetry according to the present invention, if there is no aerial photo model with overlapping space, it is possible to obtain perfect restoration model and design for restoration plan construction and construction even if there is no basic data for restoration. Rather, it uses the extracted topographic information to check the cut and fill volume compared to the previous topography, and quantitatively calculates the quantity for the restoration of the topography, thereby restoring the natural environment and ecosystem damaged indiscriminately due to the poor development. In the future, it will be effectively used to improve the quality of the land environment because it has the effect of suppressing difficult development in the land development.

Claims (3)

Terrain restoration methods using digital photogrammetry techniques that include the following steps: (a) (iii) generating an aerial photograph by scanning a film of the aerial photograph photographed before and after the development; (Ii) extracting three-dimensional spatial control points (GCPs) of the target site using a total station; (Iii) performing an aerial triangulation that connects the three-dimensional spatial coordinates (GCP) and the same point of the aerial image using a digital photogrammetry system, and forms a three-dimensional digital image space; (b) generating digital terrain model (DTM) data before and after development in the 3D digital image space using the digital photogrammetry system; (c) generating grid data including an orthoimage map and three-dimensional topographical information based on the generated digital terrain model data; And (d) Using the DTM data and the grid data before and after development, multiply the number of (-) and (+) grids by the area occupied by the actual grid in real space, ) And fill (+) areas are extracted, and the number of (-) and (+) gratings is multiplied by the area that one grating will occupy in real space, and multiplied by the value of the grating that represents the depth to cut and fill (-). ) Volume and the volume to be filled (+) to be extracted. The digital photograph of claim 1, wherein the step (a) is performed by giving 60% or more redundancy to adjacent photographs when taking aerial photographs so that at least 60% of common spaces exist in two adjacent photographs. Terrain restoration method using surveying techniques. delete

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