KR20200026012A - Method and device for making a topographic map - Google Patents

Abstract

As a preferred embodiment of the present invention, an apparatus for generating a topographic map receives an image of a specific topography, performs geometric correction by photogrammetry, and then generates a DEM image and an orthoimage. In addition, the apparatus for generating the topographic map identifies an object from the orthoimage to extract altitude information, and detects an amount of altitude change of each object in the n generated orthoimages to generate a topographic map.

Description

Method and device for making a topographic map}

The present invention relates to an apparatus and method for generating topographic maps.

The use of spatial information is a global industry of interest, and Internet-based map services and 3D geographic information services are already available from Google and Microsoft.

In addition, the 3D Geographical Information software industry market has been segmented and developed by function, and the diversity and expertise of the field of using geographic information is used to create an application field of Geographical Information System (GIS) based technology. Contributed.

 Analysis techniques using aerial photography are increasing to generate more realistic and accurate geospatial information using more accurate analysis tools such as aerial photography and aerial laser survey data.

In addition, aerial photographs provide rich texture information on the ground surface, but have disadvantages such as shadows and ups and downs, and aerial laser survey data provide highly accurate three-dimensional terrain coordinates in the form of points, but do not provide rich texture information. . In addition, it is inconvenient to manually generate a digital topographical map by manually taking survey data in the form of points.

In a preferred embodiment of the present invention, a topographic map is generated by acquiring image data in an area without building elevation information and a digital map. In particular, it is intended to generate topographic maps by automating survey data in the form of points.

Another preferred embodiment of the present invention is to provide a topographic map that provides only the objects necessary for the topographic map separately based on the object information obtained from the image taken N times the same area.

In another preferred embodiment of the present invention, deep learning-based machine learning to extract the characteristics of the object by using the change in the altitude information of the object over time in addition to the learning information for the object classified primarily, and the flow information of the river It is intended to provide a topographic map that provides such as.

In another preferred embodiment of the present invention, there is provided a topographic map in which an interface for correcting the shape of a boundary polygon and a DSM correction interface is provided.

As a preferred embodiment of the present invention, the topographic map growth unit receives an image photographed n times of a specific terrain, and performs an image correction method to perform geometric correction using an image processing unit to generate n ortho images and n DSM images; A feature classification and automatic classification unit for identifying an object in each of the n orthoimages and the n DSM images, and extracting altitude information of each of the identified objects from the n DSM images; Altitude change detection unit for detecting the altitude change based on the altitude information value of n or less of each object extracted from the terrain feature classification and the automatic classification unit; and the object identified based on the contour information and the n DSM images identified in the DEM image And a topographic map generator for generating a topographic map based on each of n or less altitude information values and an amount of change in each of the objects.

According to a preferred embodiment of the present invention, an image processor for generating n ortho images and n DSM images after performing geometric correction by photogrammetry by receiving an image photographed n times of a specific terrain; A feature classification and automatic classification unit for identifying an object in each of the n orthoimages and the n DSM images, and extracting altitude information of each of the identified objects from the n DSM images; An altitude change detection unit for detecting an altitude change amount based on n altitude information values of each object extracted from the terrain classification and automatic classification unit; And a topographic map generator configured to generate a topographic map based on the contour information determined from the DEM image, n or less altitude information values of each object determined based on the n DSM images, and an altitude change amount of each object. When there is a river in the river, the change amount of the flow amount of the river is calculated based on the change amount of altitude, and the change amount of the calculated flow amount is displayed on the topographic map.

In a preferred embodiment of the present invention, the generated topographic map further displays a boundary polygon indicating a terrain or a boundary of the detected object. In this case, a shape correction interface for receiving a correction input for correcting the boundary polygons is further provided.

In a preferred embodiment of the present invention, the topographic growth value further includes a dsm correction interface for receiving a correction input for correcting dsm data of the object identified in the corrected image.

In a preferred embodiment of the present invention, the topographic map generation unit stores and maps object identification information, coordinate information of the object, and altitude information of the object as attribute information for each of the detected objects. The coordinate information of the object is extracted from a boundary polygon indicating the boundary of the object. When the boundary polygon is corrected through the shape correction interface, the topographic map generator generates the coordinate information of the object or the altitude information of the object. The generated coordinate map is corrected by updating correction coordinate information extracted from the corrected boundary polygon.

As a preferred embodiment of the present invention, only the object whose change amount of the altitude information is equal to or less than a predetermined value is displayed on the topographic map.

In one preferred embodiment of the present invention, the change amount of the flow amount of the river is calculated based on the change amount of the altitude information, and is displayed on the topographical map.

In a preferred embodiment of the present invention, the topographic map growth value is divided into the specific terrain, and a plurality of drones simultaneously photograph each of the divided regions, and in this case, the number of the plurality of drones in the photographing area of the specific terrain, The amount, the resolution to photograph the divided region, and the flight time of each drone is determined in consideration of.

As a preferred embodiment of the present invention, the topographic map growth value is characterized in that the web server provides a topographic map generated by the topographic map generator.

According to another preferred embodiment of the present invention, a method for generating a topographic map includes receiving an image photographing a specific terrain from an image processor, performing geometric correction by photogrammetry, and then generating an orthoimage and a DSM image; Identifying an object based on the orthoimage and the DSM image by the feature classification and automatic classification unit, and extracting altitude information of each identified object from the DSM image; Photographing the specific terrain n times and detecting an altitude change amount in an altitude change detection unit based on altitude information of each of n or less objects extracted from the feature classification and automatic classification unit; And generating a topographic map in the topographic map generator based on the elevation information of the object identified from the DEM image, the altitude information of each of the objects determined based on the DSM image, and the amount of change in the altitude of each object.

According to another preferred embodiment of the present invention, a method for generating a topographic map includes receiving an image photographing a specific terrain from an image processor, performing geometric correction by photogrammetry, and then generating an orthoimage and a DSM image; Identifying an object based on the orthoimage and the DSM image by the feature classification and automatic classification unit, and extracting altitude information of each identified object from the DSM image; Photographing the specific terrain n times and detecting an altitude change amount in an altitude change detection unit based on altitude information of each of n or less objects extracted from the feature classification and automatic classification unit; Generating a topographic map in a topographic map unit based on the elevation information of each object identified based on the DEM image, the altitude information of each of the objects determined based on the DSM image, and an altitude change amount of each of the objects; The change amount of the flow amount of the river is calculated based on the altitude change amount, and the change amount of the calculated flow amount is displayed on the topographical map.

According to the present invention, there is an advantage in that it is possible to generate a topographic map by acquiring image data through an unmanned image photographing device in an area without building elevation information and a digital map.

In a preferred embodiment of the present invention, the topographic map growth value has an effect of providing a topographic map which minimizes errors due to moving objects and minimizes errors such as shadows, ups and downs, and the like through n shots.

In a preferred embodiment of the present invention, the topographical growth value has the effect of enabling fast data collection compared to the same time by simultaneously flying a plurality of drones in parallel under the most similar natural environmental conditions.

1 is a view illustrating an internal configuration of a topographical map generating apparatus as a preferred embodiment of the present invention.
FIG. 2 is a diagram for one example of controlling to photograph each divided area after dividing a specific terrain into k pieces by a flight control unit according to an exemplary embodiment of the present invention.
3 illustrates a topographic map generated by the topographic map generator as an exemplary embodiment of the present invention, and illustrates an example of correcting a boundary polygon indicating a boundary of a terrain or a detected object in the generated topographic map.
4 is a flow chart for generating a topographic map in a topographic map generating apparatus according to a preferred embodiment of the present invention.

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

1 is a view illustrating an internal configuration of a topographic map generating device according to a preferred embodiment of the present invention.

The topographic map generating apparatus 100 includes a terminal, a device, and a server capable of receiving an image through wired / wireless communication, detecting an object in the image through image processing, and calculating and processing an altitude change amount of the detected object. .

Examples of the topographic map generating device 100 include a web server, a web application, an application, a terminal, a handheld device, a wearable device, a robot, a mobile phone, a smart phone, a smart watch, a smart TV, a tablet, a notebook, a PC, a kiosk, and the like. Include.

As a preferred embodiment of the present invention, the topographic map generation method provided by the topographic map generation device 100 can be implemented in the form of an application, it can be implemented to enable the topographic map generation, correction in the terminal to install the application.

Referring to FIG. 1, the topographic map generating apparatus 100 includes an image processor 110, a feature classification and automatic classification unit 120, an altitude change detector 122, a boundary polygon extractor 130, and a DEM generator 132. ) And the topographic map generator 140. Also may further include a flight control unit (not shown).

The image processing unit 110 receives an image photographing a specific terrain, performs geometric correction by photogrammetry in the photogrammetry correction unit 114, and then generates an orthoimage produced by the orthographic projection method through the orthoimage generating unit 115. A digital surface model (hereinafter referred to as DSM image or digital surface model) is generated through the DSM generator 116 or n DSM generators 118. DSM image refers to a model that represents all the information of the real world, that is, terrain, trees, buildings, and artificial structures.

As an exemplary embodiment of the present invention, the image processing unit 110 may receive a captured image of n times photographing a specific terrain with a time difference. The image processor 110 may photograph the same specific terrain n times and distinguish between objects that are continuously detected from the n ortho images generated and objects that are not continuously detected. The image processor 110 may extract the correct shape of the object by analyzing pixel data of each object detected from the image corrected by the photogrammetry correction unit 114.

The feature classification and automatic classification unit 120 classifies a feature or feature in an image based on n DSM images or n ortho images generated based on n photographed images taken n times on a specific terrain, and performs machine learning. Automatically classify classified terrain or features.

The altitude change detection unit 122 calculates an altitude change amount of a terrain or feature based on at least one DSM image or at least one orthogonal image of n DSM images or n ortho images obtained from n-shot images taken n times of specific terrain. Can be detected.

As another preferred embodiment of the present invention, the topographic map generating apparatus 100 may further include a flight control unit (not shown) for dividing the specific terrain into k pieces and controlling each of the divided regions to simultaneously photograph the plurality of drones in parallel. Can be.

The boundary polygon extracting unit 130 determines the boundary polygon by referring to the terrain and features and the elevation change data of the terrain and the features identified through the automatic classification unit 120 and the terrain and the feature of the elevation change detection unit 122. Can be extracted.

When the boundary polygons are extracted, the DEM generator 132 generates a digital elevation model (DEM image). The DEM image represents the elevation of the terrain only, which does not include vegetation and artifacts, and the DEM height of the river or lake represents the water surface.

The topographic map generator 140 may generate a topographic map by referring to the DEM image generated by the DEM generator 132 and display the generated topographic map on a display. In this case, the boundary polygon extraction unit 130 displays the boundary polygons extracted by the boundary polygon extraction unit 130 on the topographic map, and provides the shape correction interface 144 or the DSM correction interface 146 to the user to extract the boundary polygons. Wrong parts and DSM can make corrections manually.

Referring to FIG. 2, the flight control unit divides a specific terrain into seven and shows an embodiment in which seven drones simultaneously take parallel photographs along respective flight paths S201 to S207.

The flight controller can set the number of drones that have taken a particular terrain in consideration of the shooting area of the specific terrain, the amount of light, the resolution of shooting the divided area, and the flight time of each drone. Areas, flight paths for each drone, etc. can be set. The flight controller may photograph the specific terrain divided into k times and then provide the captured image to the image processor 110.

The flight controller may divide the specific terrain into a plurality of divided regions based on the characteristics of the terrain determined based on the captured image photographed schematically about the specific terrain. In one embodiment, when there is a river in a particular terrain, the flight path may be set so that the river area is divided into divided areas and one drone photographs only the river area along the path of the river.

In an exemplary embodiment of the present invention, the image processing unit 110 receives k images from each of the k regions at a first time, and receives k images received through the photogrammetry correction unit 114 using a photogrammetry technique. After the correction, the first orthogonal image corresponding to the first shooting time is generated, the second orthogonal image corresponding to the second shooting time is generated in the same manner, and the nth orthogonal image is generated at the nth shooting time. Can be. In this case, the image processor 110 may generate one DSM image based on at least one image of n photographed images or n ortho images for the DSM image of the specific terrain.

For example, referring to FIG. 2, seven images are received in each of the seven areas S201 to S207 at t1 time to generate a first orthogonal image, and a second orthogonal image is generated at t2 time in the same manner. An nth orthoimage may be generated at a time tn.

In one preferred embodiment of the present invention, the image processing unit 110 generates n orthoimages or n DSM images, and then further adds data of the feature classification and automatic classification unit 120 and the altitude change detection unit 122. It can be implemented to generate one DEM image by using.

In a preferred embodiment of the present invention, the feature classification and automatic classification unit 120 classifies a feature and detects an object through machine learning in each of n ortho images or n DSM images generated by the image processor 110. The altitude change detection unit 122 may extract altitude information for each object.

The feature classification and automatic classification unit 120 detects and classifies objects in n ortho images through machine learning. Then, altitude information or coordinate information may be mapped to each identified object. The method of identifying an object in an orthoimage may use machine learning to detect the object. In machine learning, coordinate information of pixels constituting an object, color information of pixels, altitude information of pixels, and the like may be used.

 The feature classification and automatic classification unit 120 may determine that the object has moved or disappeared when the detected object has less than n altitude information. For example, in three orthoimages of five orthoimages, an object P is detected at points (x1, y1) to (x2, y2), but (x1 ', y1') in the fourth and fifth orthoimages. If an object named P is not detected at the ~ (x2 ', y2') and neighboring points, the object may be moved or disappeared.

As a preferred embodiment of the present invention, the feature classification and automatic classification unit 120 extracts the altitude information only when each object has more than a predetermined number of altitude information, and has less than the predetermined number of altitude information. May not extract altitude information. The object from which the altitude information is not extracted may be deleted when the topographic map generation unit 140 generates the topographic map.

The feature classification and automatic classification unit 120 extracts the altitude information from the altitude change detection unit 122 only when the object has altitude information of a predetermined number or more. In this case, when the object has more than a preset number of altitude information based on the latest time point, it is determined that the object exists and the altitude information is extracted.

For example, if images were taken five times in June, July, August, September, and October, the orthoimages taken in June, July, and August were detected objects, but September and 10 The object not detected in the orthoimage captured in the month may not use the related information when generating the topographic map.

In another embodiment, when the image was taken five times in June, July, August, September, and October, the object was not present in June and July, but in August, September, and 10 Objects not detected in the orthoimage captured in the month may be added to the topographic map generation. In this case, the object may be newly detected by indicating that the object is detected only in some of the n images in the topographic map. In the above-described embodiment, an example in which an ortho image is taken by one month is noted, but it should be noted that the ortho image may be photographed at various time intervals such as minutes, hours, or weeks.

According to an exemplary embodiment of the present invention, the variation detection unit 130 detects an elevation variation based on the altitude information of each object extracted from the n orthoimages. The change detection unit 130 may detect only the change amount of the altitude information or calculate the change amount of the altitude information according to the change amount of time. The change detection unit 130 may classify the object as a moving object when the speed of the altitude change is fast. The change amount detection unit 130 may also detect a change in the flow amount of the river, a landslide occurrence, an avalanche, an overflow situation, etc. based on the change amount of the altitude information. In addition, the change amount detection unit 130 may display the detected change amount together with the topographic map. Display methods include text, color, voice, and the like.

As a preferred embodiment of the present invention, the topographic map generation unit 140 is based on the contour information grasped in the DEM image and the n or less altitude information values of each object grasped based on the n orthoimages and the altitude change amount of each object. Create a topographic map.

As a preferred embodiment of the present invention, the topographic map generator 140 is based on the contour information grasped from the DEM image, the altitude information value of the object selectively extracted from the n orthoimages, and the DEM image generated by the DEM generator 132. Create a topographic map with The topographic map generation unit 140 may selectively use only the altitude information value of the object in which m or more objects (m is a natural number less than n) detected as the same object in the n orthoimages. When there are less than m objects estimated to be the same object in n orthoimages, information related to the object may be selectively excluded.

The topographic map generation unit 140 may include a boundary polygon display unit 142 and a DSM correction interface 146, and the boundary polygon display unit 142 may further include a shape correction interface 144.

FIG. 3 illustrates a topographic map generated by the topographic map generator 140, and further illustrates boundary polygons 310a, 310b, and 310c indicating a boundary of a terrain or a detected object in the generated topographic map.

Referring to FIG. 3 further, the topographic map generation unit 140 may further display the boundary polygons 310a, 310b, and 310c indicating the boundary of the terrain or the detected object. Also, the contour information can be displayed on the topographic map.

When the topographic map generation unit 140 displays the boundary polygons 310a, 310b, and 310c, the topographic map generation unit 140 may provide a shape correction interface 144 to modify the boundary polygons 310a, 310b, and 310c to the user. The user may correct the shape of the object using the shape correction interface 144, and when the user corrects the shape of the object, the boundary polygons 320a, 320b, and 320c may be corrected together.

Similarly, the topographic map generator 140 may provide the user with a dsm correction interface 146 that receives a correction input for correcting the dsm data, and corrects the DSM image accordingly when the user corrects the dsm data. .

To this end, the topographic map generator 140 stores and maps object identification information, coordinate information of the object, and altitude information of the object for each object of the generated topographic map. In this case, the initial coordinate information of the object may be extracted from a boundary polygon indicating the boundary of the object. When the boundary polygon or dsm data is corrected through the shape correction interface 144 or the dsm correction interface 146, the topographic map generation unit 140 converts the coordinate information of the object or the altitude information of the object that has been mapped to the attribute information from the corrected boundary polygon. It is implemented to correct the generated topographical map by updating with the extracted correction coordinate information or the altitude information based on the corrected dsm data.

FIG. 2 is a diagram illustrating an embodiment in which a plurality of drones or a plurality of unmanned image photographing apparatuses photograph a divided terrain by dividing a specific terrain into k pieces.

When the natural environment changes when shooting a certain terrain, errors frequently occur in the DSM image or the ortho image. In particular, clouds at the time of shooting, soils in rivers, changes in agricultural lands, and shadows of mountain slopes facing the sun are the main causes of errors in DSM or ortho images.

According to an exemplary embodiment of the present invention, natural environment conditions for photographing a specific terrain are set to be as similar as possible, and by splitting the specific terrain, the k regions S201 to S207 divided in parallel are simultaneously photographed to change the natural environment conditions. It is possible to reduce and improve the error of the DSM image or the ortho image caused.

4 is a flowchart for generating a topographic map in a topographic map generating apparatus according to an embodiment of the present invention.

The topographical growth value is received by the image processing unit to receive the image of the specific terrain, and performs geometric correction by photogrammetry to generate an orthoimage and a DSM image (S410).

The altitude information extracting unit identifies the object in the orthoimage and the DSM image generated by the image processing unit, and extracts altitude information of each identified object (S420). In this case, the altitude information extractor may extract less than n pieces of altitude information for each object extracted from each of the n imaging apparatuses photographing the specific terrain n times, and the variation detection unit detects the altitude change amount using the extracted information ( S430).

Thereafter, the topographic map generator generates a topographic map based on the elevation information of each object identified based on the contour information and the orthoimage or the DSM image, and the altitude change amount of each object (S440).

In the above description, the technical idea of the present invention has been described with the accompanying drawings. However, the present invention has been described by way of example only, and is not intended to limit the present invention. In addition, it is apparent that any person skilled in the art to which the present invention pertains can make various modifications and imitations without departing from the scope of the technical idea of the present invention.

Claims (1)

An image processor for receiving n images of a particular terrain and performing geometric correction by photogrammetry to generate n ortho images and n DSM images; A feature classification and automatic classification unit for identifying an object in each of the n orthoimages and the n DSM images, and extracting altitude information of each of the identified objects from the n DSM images; Altitude change detection unit for detecting the altitude change based on less than n altitude information values of each object extracted from the terrain feature classification and the automatic classification unit; and the object identified based on the contour information and D n images identified in the DEM image A topographic map generator comprising: a topographic map generator for generating a topographic map based on each of n or less altitude information values and an amount of change of each object.

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