JP5947666B2 - Traveling road feature image generation method, traveling road feature image generation program, and traveling road feature image generation apparatus - Google Patents

Description

  The present invention relates to a on-road feature image generation method that can be obtained in a format in which an image of a feature of a predetermined height or more existing around and directly above a travel route can be defined on a map.

  Around the road, electric poles, electric poles, communication cables, and roadside trees are installed as electric poles, or guide boards are provided. In addition, signs are provided on buildings around the road. Furthermore, there are cases where electric wires and communication cables are drawn across the power poles on both sides of the road.

  Such road features are mostly visually inspected by the road manager's workers from the vehicle.

  However, since visual inspection takes time and money, as shown in Patent Document 1, for example, there is a technique for grasping the hanging state of the electric wire by laser measurement.

  In Patent Document 1, a laser scanner is mounted on a vehicle, laser data based on the reflected pulse of the laser scanner is defined in a three-dimensional space, and a wire in the ZY plane or ZX plane (lateral) is defined. Is extracted. At this time, it is disclosed that a rectangular solid is generated in the entirety between the utility poles and the electric wire is detected from a point group in the rectangular solid.

JP 2009-68951 A

  However, the electric wire is not only the surroundings. There are also wires that cross the road and connect to the utility poles on both sides.

  However, in Patent Document 1, a rectangular solid is defined between the utility poles on the roadside and the electric wire is detected by viewing the rectangular solid from the lateral direction. Therefore, in this rectangular parallelepiped, the electric wires straddling the road are extracted. Can not do it.

  On the other hand, there is a geographic information system (GIS) that displays a map. This geographic information system defines a map in a two-dimensional plane (XY plane).

  On the other hand, since the electric wire of patent document 1 is not the data defined in the XY plane, the roadside and the electric wire on a road, a communication cable, a streetlight, a tree, etc. (feature on a road) are easily on a map. Cannot be defined.

  There is also a desire to extract only features existing at a predetermined height from the road surface.

  However, patent document 1 cannot respond to such a request.

  The present invention has been made in view of the above-described problems, and is an on-road feature image obtained in a format in which an image of a feature of a predetermined height or more existing around or directly above a road can be easily defined on a map. The purpose is to obtain a generation method.

The on-road feature image generation method of the present invention includes a GPS receiver and a high-density laser device mounted on a vehicle, and a laser is emitted at intervals of several centimeters while scanning from the high-density laser device to a target range while traveling on the road. Based on the laser data (DLi) of the output range (Di) of the point cloud of the high-density laser data (Li) obtained by launching, the three-dimensional space region (JDBi) within a predetermined height range from the traveling road surface of the vehicle A method for generating a feature image on a traveling road to obtain a laser orthophoto image of the
An image memory for display,
First storage means for storing a point cloud of laser data (DLi) in the output range (Di);
Second storage means for storing a three-dimensional position (Pni) of the GPS receiver constituting a movement locus (Pi) of the GPS receiver;
The search lower limit value (hs1) longer than the length (Hai) from the three-dimensional position (Pni) of the GPS receiver to the plane of the travel path and the laser point group below the three-dimensional position (Pni) are not searched. A third space that stores the three-dimensional space region formation information including a search unnecessary length (hs2: hs2 ≧ hs1) for determining the range and a predetermined height (hss1) from the surface of the traveling road to the three-dimensional space region (JDBi). Storage means;
A fourth storage means for generating a search area (Ci) for determining laser data (CLpai) of the surface of the traveling path immediately below the three-dimensional position (Pni) of the GPS receiver;
Fifth storage means for generating the three-dimensional space area (JDBi);
Prepare
Computer
(A1). Sequentially reading out the three-dimensional position (Pni) of the GPS receiver within the output range (Di) from the second storage means and sequentially defining it in the fourth storage means;
(A2). A perpendicular line (Pzi) is defined for each of the three-dimensional positions (Pni) defined in the fourth storage means, and a cylinder having a radius (Ri) is removed from the perpendicular line (Pzi) without the search unnecessary length (hs2). Generating the search area (Ci) of height length Chi (Chi = hs1-hs2) in the fourth storage means;
(A3). For each search area (Ci), the laser data (DLi) having the three-dimensional coordinates in the search area (Ci) is read from the storage means 1, and the laser data (in the search area (Ci)) ( Storing as CLi);
(A4). For each search area (Ci), a point group other than the road surface is removed from the point group of the laser data (CLi) stored in the search area (Ci), and the vertical line (Pzi) Determining nearby laser data as the laser data (CLpai) immediately below the three-dimensional position (Pni);
(A5). Each time the three-dimensional position (Pni) is defined in the fourth storage means, the laser data (CLpai) immediately below having the two-dimensional coordinates (x, y) of the three-dimensional position (Pni) is searched. , Updating the three-dimensional position (Pni) to the searched laser data (CLpai) immediately below, and defining it as the three-dimensional position (Pni ′) in the fifth storage means;
(A6). Between the three-dimensional position (Pni ′) defined in the fifth storage means and the next three-dimensional position (Pni ′ + 1), a predetermined height of the three-dimensional space region formation information of the third storage means Forming the three-dimensional space region (JDBi) at (hss1);
(A7). The laser data ((DLi)) having the three-dimensional position (Pin ′) in the three-dimensional space area (JDBi) generated in the fifth storage means is read from the first storage means, and this is read into the three-dimensional space. Storing the laser data (JDLai) in the region (JDBi) in the three-dimensional space region (JDBi);
(A8). Pixels (Gpi) of the image memory for display are sequentially designated, and for each designation, a region corresponding to the pixel (Gpi) is retrieved from the three-dimensional space region (JDBi), and laser data in the retrieved region is obtained. A step of calculating an average of the reflection intensity of (JDLai);
(A9). The gist is to write the gray scale value corresponding to the average value to the pixel (Gpi) of the image memory for display to obtain the laser orthophoto image (RGai).

  As described above, according to the present invention, a three-dimensional space region straddling the traveling road at a predetermined height from the traveling road surface is generated, and laser data is stored in the three-dimensional space region to correspond to the pixels of the display image memory. A laser orthophoto image obtained by orthographic projection is obtained by assigning a gray scale value corresponding to the reflection intensity of laser data in a pixel in a three-dimensional space region to a pixel in a display image memory.

  For this reason, it is possible to obtain an image such as a photograph of only an electric wire over the road, an electric wire around the road, a tree crown, a signboard, and a streetlight.

  Furthermore, even if the original is laser data, it is a laser orthophoto image as if it was orthographically projected, so it can be easily associated with a map.

It is a schematic block diagram of the on-road feature image generation apparatus 1 using the high-density laser data according to the first embodiment. It is a schematic block diagram of the measuring apparatus mounted in the laser measurement vehicle. It is explanatory drawing of the laser point group Li of the database 10. FIG. It is explanatory drawing explaining the relationship of each mesh layer. It is explanatory drawing of the image of the laser point group which lowered the viewpoint to the vicinity of the measuring apparatus and made the viewpoint direction look forward. It is explanatory drawing of the production | generation of the solid space area | region for electric wires. It is a flowchart explaining operation | movement of the movement locus lower road surface point determination part 610. FIG. It is a flowchart explaining operation | movement of the movement locus lower road surface point determination part 610. FIG. It is explanatory drawing explaining the production | generation of the search range Ci. It is a flowchart explaining the process of an electric wire solid space area | region production | generation part and an electric wire area | region point group cut-out part. It is a flowchart explaining the process of an electric wire solid space area | region production | generation part and an electric wire area | region point group cut-out part. It is explanatory drawing explaining the definition of road width Wi. It is explanatory drawing explaining the production | generation of an electric wire solid space area | region. It is explanatory drawing explaining the production | generation of an electric wire solid space area | region. It is explanatory drawing explaining the laser orthophoto image of an electric wire solid space area | region. It is explanatory drawing of the laser ortho image containing a road surface. It is explanatory drawing explaining the storage of laser data to a road solid space area. It is explanatory drawing of the laser orthophoto image which looked at the road from the top. It is a schematic block diagram of the feature image generation apparatus on a driving road at the time of providing a low-resolution hierarchization part. It is a flowchart explaining the feature image generation apparatus on a driving road at the time of providing a low-resolution hierarchization part. It is explanatory drawing explaining the correspondence of the pixel of an original image, and the pixel of a low resolution image. It is explanatory drawing of the reflection intensity calculation result table 180i for every low resolution image. It is explanatory drawing of the laser orthophoto image RGbi for the road surfaces of the normal process which does not use the low resolution image hierarchization part 220. FIG. It is explanatory drawing at the time of making the 1 cm resolution road area | region laser orthophoto image RGbi of FIG. 23 into 5 cm resolution by the low resolution image hierarchization part.

  The following embodiments exemplify apparatuses and methods for embodying the technical idea of the present invention, and the technical idea of the present invention is specified as follows in terms of structure and arrangement. It is not a thing. The technical idea of the present invention can be variously modified within the technical scope described in the claims. It should be noted that the drawings are schematic and the configuration of the apparatus and system is different from the actual one.

  The on-road feature image generation method (apparatus) using high-density laser data according to the present embodiment may use high-density laser data obtained by an aircraft, a railway vehicle, or the like, but in this embodiment, An apparatus using high-density laser data obtained by attaching a high-density laser measuring machine to a vehicle will be described.

  FIG. 1 is a schematic configuration diagram of an on-road feature image generating apparatus 1 using high-density laser data according to the first embodiment. In the present embodiment, it is assumed that “on the road” includes a predetermined height region from the road surface and a predetermined height around the road.

  Further, the features on the traveling road include an electric wire, a communication cable, a signboard, a building, a tree trunk, a streetlight, a signal, a guide board, and the like at a predetermined height from the road surface.

  As shown in FIG. 1, the on-road feature image generating apparatus 1 (computing system: composed of a display unit, a keyboard, a CPU, a RAM, a ROM, a graphic accelerator, and the like) according to the first embodiment has a high density. A database 10 storing laser data Li (x, y, z, reflection intensity in, emission time, reception time) is provided.

  The program configuration includes an output range laser data extraction unit 20, a laser data display unit 40, a cut solid creation / point cloud reading unit 60, a laser ortho image creation unit 90, a display image memory 70, and an image output unit. 80, etc., stored in the ROM, read into the RAM and executed.

  That is, with these programs, a GPS receiver and a high-density laser device are mounted on the vehicle, and a laser is emitted at intervals of several centimeters while traveling from the high-density laser device to the target range while traveling on the road. A laser in which a three-dimensional space region (JDBi) is orthographically projected within a predetermined height range from the traveling road surface of the vehicle based on laser data (DLi) of an output range (Di) of a point group of high-density laser data (Li) An orthophoto image is obtained on the display unit.

  The above-described high-density laser data Li is measured by, for example, the laser measurement vehicle 2 shown in FIG.

  For example, as shown in FIG. 2, the laser measurement vehicle 2 has a high-density laser scanner 2a, 2b, 2c (simply called a high-density laser device) and a GPS receiver 2d mounted on the vehicle. ing. A plurality of cameras may be provided. These laser scanners have a range of 80 m to 100 m, and measure a range of 180 degrees, 270 degrees, or 360 degrees around 45 degrees.

  The acquired high-density laser data Li includes the three-dimensional coordinates (x, y, z) of the spot point of the object irradiated with the laser, the emission time of the laser data Li, the reception time, the reflection intensity In, etc. It is composed of GPS data (also referred to as a movement trajectory) is also acquired. These are stored in the ROM 3.

  Note that the GPS data may correspond to the laser data Li. Further, since the laser data Li has a large amount of data, it is divided into a plurality of files and stored.

  Further, the laser measurement vehicle 2 includes a recording unit (not shown) for recording the acquired data, a hybrid inertial navigation device or the like (not shown), and can acquire the position / posture of the automobile. . The position and orientation acquired by these hybrid inertial navigation devices may be stored in correspondence with each three-dimensional position Pni of the movement locus Pi.

  The three-dimensional coordinates (x, y, z) of the spot point of the object are obtained using the position and orientation of the hybrid inertial navigation apparatus, the GPS position, and the like.

  The laser scanners 2a to 2c described above are disposed so as to be inclined at 45 degrees in the horizontal direction, and the pitch interval is set to 0.5 cm, 1 cm, 2 cm, 3 cm, 4 cm or 5 cm, respectively.

  That is, in the database 10, as shown in FIG. 3, the laser data Li (L1, L2,...) Is associated with its three-dimensional coordinates (x, y, z), reflection intensity, launch time, and the like. Is remembered.

  The output range laser data extraction processing unit 20 reads the input minimum mesh size (1 cm × 1 cm, 10 cm × 10 cm, or 1 m × 1 m) (1 m × 1 m in the present embodiment), and this minimum mesh size (1 m × 1 m). ) Is generated in the memory 21a, and upper mesh layers having a mesh (lattice) of 10 times, 100 times,... Are created in the memories 21b, 21c,.

  Then, the high-density laser data Li ((x, y, z), reflection intensity in,) stored in the database 10 is stored in the corresponding mesh of the minimum mesh layer (same as the above coordinate system), and this minimum The high-density laser data of the minimum mesh layer is thinned out and stored in the upper mesh layer with respect to the mesh (for example, 1/10).

  The output range laser data extraction unit 20 reads the input output range Di, reads the point group of the laser data Li corresponding to the output range Di from the memory 21a (minimum mesh), and stores it in the memory 30 (this). Is referred to as a point cloud of the output range laser data DLi).

  The laser data display unit 40 reads the input viewpoint SCi (position) and direction Hci, selects a mesh layer (21a or 21b...) Corresponding to the viewpoint SCi (position), and projects the laser data projected in the direction Hci. DLi (also referred to as original data) is read and output to the image output unit 50 to display the laser point group (see FIG. 5).

  The output range laser data extraction processing unit 20 will be described in detail later with reference to the drawings.

  The cut-out solid creation / point cloud reading unit 60 subtracts the vehicle height from the GPS receiver movement locus Pai or the GPS receiver, which is the movement locus Pi of the memory 50, and reads this as the movement locus Pbi (for example, 2. 5m intervals). In the present embodiment, the movement locus Pai of the GPS receiver will be described.

  Then, the laser data CDLpai immediately below each three-dimensional position Pnai of the movement locus Pi (Pai) is searched from the memory 30.

  The three-dimensional coordinates of the retrieved laser data CDLpai are defined in the memory 680 as a three-dimensional position Pnai ′ constituting the movement locus Pai. That is, the three-dimensional position Pai (x, y, z) constituting the movement locus Pai is changed (updated) to the three-dimensional coordinates of the laser data CDLpai.

  Then, the input road width Wi and the like are sequentially generated between each Pnai ′ to generate the three-dimensional space area Ji. In the present embodiment, an electric wire is taken as an example, and the three-dimensional space area Ji is referred to as an electric wire three-dimensional space area JDBi.

  FIG. 6 is an explanatory diagram of solid generation for electric wires.

  As shown in FIG. 6, the wire solid space region JDBi described above has a distance hss1 (for example, 4 m) from the road surface to the lower limit end Zss1 of the wire solid space region JDBi, and the uppermost end Zss2 of the wire solid space region JDBi from the road surface. Distance hss2 (for example, 6 m) and a horizontal width Wi. The difference between the lower limit end Zss1 (distance hss1) and the uppermost end Zss2 (distance hss2) is the thickness DBHi.

  The lower limit end Zss1 and the uppermost end Zss2 of the wire three-dimensional space area JDBi indicate the Z value of the coordinate system in the memory 680.

  And the point group contained in the electric wire solid space area JDBi of the output range laser data DLi is read from the memory 30 and stored. In this embodiment, the output range laser data DLi stored in the wire three-dimensional space area JDBi is referred to as laser data JDLai.

  The method for determining the three-dimensional position Pnai ′ of the moving locus and the method for creating the wire solid space area JDBi will be described later.

  The laser orthoimage creation unit 90 defines the display image memory 70 (resolution of 5 cm or less) with the input resolution (5 cm or less). Then, the wire solid space area JDBi (J1, J2...) Of the memory 680 is assigned in order, and the pixels of the display image memory 70 are designated in order each time the wire is assigned, and the wire solid space area JDBi corresponding to this pixel is designated. The reflection intensity Ini of the laser data JDLai stored in the area (also referred to as mesh) is read.

  Then, a gray scale value corresponding to the reflection intensity is assigned to the pixel (display image memory 70) to obtain a laser orthophoto image. This is also referred to as an original image GDi in the present embodiment. That is, since the gray scale value corresponding to the reflection intensity of the laser data in the pixel of the wire solid space region JDBi corresponding to the pixel of the display image memory 70 is directly assigned to the pixel of the display image memory 70, the orthographic projection is performed. Such an image (referred to as a laser orthophoto image) is obtained.

  Therefore, since the pixels of the laser orthophoto image are indicated by two-dimensional coordinates, they can be easily associated on the map (defined by two-dimensional coordinates).

  In the original image GDi, for example, an electric wire is called a laser orthophoto image GRgai for an electric wire, and a road surface is called a laser orthophoto image GRgbi for a road.

  That is, the wire solid space region JDBi (J1, J2...) Is assigned in order, and the original image GDi is generated every time it is assigned, and as a result, the original image GDi (output range Di) connecting the wire solid space region JDBi. Have gained.

  The image output unit 80 outputs the laser point group (see FIG. 5) from the laser data display unit 40 (including the laser point group display image memory) or the original image GDi of the display image memory 70 to the display unit 100. Display.

  The cut solid creation / point group reading unit 60 includes a road surface point determination unit 610 under a movement locus, an electric wire region generation unit 650, and an electric wire region point group cut unit 670, as shown in FIG. The wire solid space region JDBi is generated so as to straddle a predetermined height from the road, and the laser data is read from the memory 30 and stored in the wire solid space region JDBi (JDLai).

  Further, a memory 620 storing road surface point search parameters and a search range Ci for obtaining a laser point CDLpai (Pnai ′) on the road surface immediately below the three-dimensional position Pnai of the movement locus Pai of the GPS receiver are generated. Memory 640 (also referred to as a road surface point search box memory), a memory 630 in which the laser point CDLpai directly below is stored, a memory 660 in which parameters for the electric wire region are stored, and a wire solid space region JDBi are generated. A memory 680 (also referred to as an electric wire region cutting solid memory) or the like is used.

  The aforementioned road surface point search parameters include a search range Ri (radius, for example, radius 15 cm, 12.5 cm, or 20 cm,..., 15 cm in the present embodiment) and a lower search lower limit distance hs1 (for example, 3 m) from the GPS receiver. And a downward search unnecessary distance hs2 (1 m) from the GPS receiver (see FIG. 9).

  The electric wire region parameters are a distance hss1 (for example, 4 m) from the road surface to the lower limit end Zss1 of the electric wire solid space region JDBi, and a distance hss2 (for example, 6 m) from the road surface to the uppermost end Zss2 of the electric wire solid space region JDBi. And a horizontal width Wi (see FIG. 13).

  Below, the movement locus lower road surface point determination unit 610 will be described with reference to the flowcharts of FIGS. In the present embodiment, description will be made assuming that the movement locus Pai of the GPS receiver mounted on the vehicle is stored in the memory 50.

  Further, as shown in FIG. 7, the road surface point determination unit 610 directly below the movement trajectory includes a horizontal search range Ri from the road surface point, a lower search lower limit distance hs1 (for example, 3 m) from the GPS receiver, and GPS reception. A screen (not shown) for inputting the downward search unnecessary distance hs2 (1 m) from the container is displayed (S61).

  The lower search lower limit distance hs1 (for example, 3 m) from the GPS receiver is input as 3 m when the height of the GPS receiver from the road surface is 2 m. This is because the GPS data may have an error of about ± 1 m in the height direction, so that the search range Ci is a cylinder Ci of ± 1 m from the road surface. Note that a distance of 1 m from below the road surface is referred to as a downward search distance hs3.

  Next, the search range Ri (for example, 15 cm), the lower search lower limit distance hs1 (for example, 3 m) from the GPS receiver, and the lower search unnecessary distance hs2 (for example, 1 m) from the GPS receiver are read into the memory 620. Store (S62: see FIG. 9).

  The search range Ri (for example, 15 cm), the lower search lower limit distance hs1 (for example, 3 m) from the GPS receiver, and the lower search unnecessary distance hs2 from the GPS receiver are collectively referred to as road surface point search parameters. The lower search lower limit distance hs1 (for example, 3 m) from the GPS receiver and the lower search unnecessary distance hs2 from the GPS receiver are collectively referred to as a vertical direction search range.

  Each value of the road surface point search parameter is arbitrary, and the road surface point direct determination unit 610 directly below the movement locus causes the screen 100 to display and input a road point search parameter input screen (not shown).

  Next, the road surface point direct determination unit 610 immediately below the movement locus reads each three-dimensional position Pai (x, y, z: every 2.5 m)) of the movement locus Pi of the GPS receiver stored in the memory 620. The road surface point search box memory 640 is sequentially stored (S63: see FIG. 9). As shown in FIG. 9, the road surface point search box memory 640 defines a three-dimensional coordinate system.

  Next, a cylinder CCi of the road surface horizontal search range Ri is generated in the road surface point search box memory 640 around the read three-dimensional position Pnai (x, y, z) (S65: see FIG. 9). .

  Next, the road surface point search box memory that reads the road surface point search parameters in the memory 620 and takes the lower search lower limit distance hs1 (for example, 3 m) vertically from the three-dimensional position Pai (x, y, z). The Z value on the three-dimensional coordinate at 640 is defined as the lower search lower limit height ZS1 (S66: see FIG. 9). At this time, the x and y coordinates of the three-dimensional position Pai are also defined.

  Then, the Z value on the three-dimensional coordinates in the memory 640 for the road surface point search box, which takes the downward search unnecessary distance hs2 (for example, 1 m) vertically from the three-dimensional position Pai of the movement locus Pi of the GPS receiver, is calculated as the road surface point. It is defined as the search upper limit height ZS2 of the search box Ci (also referred to as search range Ci) (S67a: see FIG. 9). At this time, the x and y coordinates of the three-dimensional position Pai are also defined.

  Then, a value Chi obtained by subtracting the lower search unnecessary distance hs2 from the lower search lower limit distance hs1 is obtained, and a Z value (search lower limit height ZS1) in the coordinate system of the memory 640 that takes Chi from the search upper limit height ZS2 is obtained. The position is defined in the memory 640 (S67b).

  Next, the cylinder of the search range Ri in the range of Chi (search lower limit high ZS1, search upper limit high ZS2) is set as the search range Ci (S67c).

  That is, as shown in FIG. 9, a search range Ci on a 2 m cylinder having a radius of 15 cm (Ri) is generated 1 m below the GPS receiver.

  Next, as shown in FIG. 8, the determination unit 610 directly below the road surface point immediately below the movement trajectory stores a point group (including one) of the laser data DLi included in the search range Ci from the memory 30. (S71). The laser data DLi read in the search range Ci is referred to as CDLi.

  Then, a median filter is applied to all the laser data CDLi in the search range Ci to remove noise to determine laser data CDLpi having a Z value of the road surface immediately below the three-dimensional position Pai (S72). That is, the Z values of all the laser data CDLi in Ci are acquired, sorted in the order of height, and the median value among all the data is the Z value of the road surface immediately below the three-dimensional position Pai. Is determined as laser data CDLpi.

  In addition to the median filter, for example, it may be determined by a process using the mode value. Thereby, only the laser point group CDLpi on the road surface can be obtained.

  Next, a perpendicular line PZi is drawn from the three-dimensional position Pnai of the movement locus Pi of the GPS receiver to the search range Ci, and it is determined whether or not there is a laser point group CDLi (including one) intersecting this (S73).

  If it is determined in step S73 that the laser data CDLi exists (Yes), the laser data CDLi is determined as the laser data CDLpai on the road surface immediately below the three-dimensional position Pnai of the movement locus Pi of the GPS receiver (S75). Then, the data is stored (Pi, Pnai, CDLpai) corresponding to the memory 630 (S76). That is, the three-dimensional position Pnai of the movement locus Pi of the GPS receiver is updated to the coordinate value of CDLpai.

  If it is determined in step S73 that the laser point group CDLi does not exist immediately below the three-dimensional position Pnai constituting the movement locus Pi of the GPS receiver (NO), the laser point closest to the perpendicular PZi (horizontal distance). The group CDLi is determined as the laser point CDLpai on the road surface (S74), and the process proceeds to step S75.

  Then, it is determined whether or not there is another three-dimensional position Pnai of the movement locus Pi of the GPS receiver (S76). If there is another three-dimensional position Pnai of the movement locus Pi of the GPS receiver in step S76, it is updated to the next three-dimensional position (Pnai + 1) and the process returns to step S64 in FIG. 8 (S77).

  Next, operation | movement of the electric wire area | region area | region production | generation part 650 and the electric wire area | region point group cutting part 670 is demonstrated below using the flowchart of FIG.10 and FIG.11.

  The wire region in-point point cutout unit 92 includes a wire search upper limit value hss2 (for example, 6 m), a wire search lower limit value hss1 (for example, 4 m: also referred to as a wire search unnecessary region), and a road width Wi (for example, 8 m) ( A screen for input (generally referred to as a wire region parameter) is displayed and input (S81).

  Next, the electric wire region parameters (hss1, hss2, Wi) are read and stored in the memory 630 (S82).

  Next, the x, y, and z coordinate values of the laser data CDLpi immediately below the three-dimensional position Pnai of the movement locus Pi of the GPS receiver are sequentially read from the memory 630, and this is read on the road surface immediately below the three-dimensional position Pnai ( The three-dimensional position Pnai ′ of the travel path) is defined in the electric wire region cutting-out memory 680 (a three-dimensional coordinate system is defined) (S83).

  Next, the road width Wi is defined in these three-dimensional positions (Pnai′-1, Pnai ′, Pnai ′ + 1, Pnai ′ + 2,...) (S84).

  The road width Wi is defined by connecting the three-dimensional positions Pnai ′ with a straight line Pnni and crossing the straight line Pnni at a right angle as shown in FIG.

  Then, the three-dimensional position Pnai ′ of the movement trajectory on the road surface defined in the electric wire region cutting-out memory 680 is set (S85).

  Next, a perpendicular line Fi is drawn on the basis of this three-dimensional position Pnai ′, and the electric wire search upper limit value hss2 in the memory 660 is converted into a coordinate value in the electric wire region cutting-out memory 680 (search upper limit height Zss2), and The electric wire search lower limit hss1 is converted into a coordinate value in the electric wire region cutting-out memory 680 (search upper limit height Zss1), and these three-dimensional positions are defined in the memory 680 (S86).

  Next, the road width Wi defined in step S84 is translated on the vertical line Fi and defined as the search upper limit height Zss2 and the search upper limit height Zss1 (S88). In FIG. 13, the road width Wi defined as the search upper limit height Zss1 is described as Wi ′, and the road width Wi defined as the search upper limit height Zss2 is described as Wi ″.

  Next, it is determined whether Wi ′ and Wi ″ are defined for the next three-dimensional position Pnai ′ + 1 of the three-dimensional position Pnai ′ of the movement trajectory on the road surface (S89).

   If it is determined in step S89 that Wi ′ and Wi ″ are not defined for the next three-dimensional position Pnai ′ + 1, the three-dimensional position Pnai ′ of the road surface movement locus is changed to the next road surface movement locus. The three-dimensional position Pnai ′ + 1 is updated, and the process returns to step S85 to define Wi ′ and Wi ″ on the next three-dimensional position Pnai ′ + 1.

  In step S89, when it is determined that Wi ′ and Wi ″ are defined for the next three-dimensional position Pnai ′ + 1, as illustrated in FIG. 11, the width Wi ′ and the width Wi of the three-dimensional position Pnai ′. A solid space region (Q1, Q2,..., Q8) surrounded by ″ and Wi ′ and Wi ″ of the next three-dimensional position Pnai ′ + 1 is defined as a wire solid space region JDBi (S91: FIG. 14). reference). Points Q1, Q2,... Q8 are defined by three-dimensional coordinate values.

  That is, as shown in FIG. 14, an electric wire solid space region JDBi having a distance of 4 m, for example, and a thickness of 2 m, a width of 8 m, and a depth of 2.5 m is defined (generated) in the memory 680 on the road surface.

  Next, the electric wire area point group cutout unit 670 reads (cuts out) and stores (cuts out) all the output range laser data DLi having the coordinate values in the electric wire solid space area JDBi generated in the memory 680 from the memory 30. (S92a). This point group is referred to as the wire solid space area laser data JDLai.

  Next, the electric wire area point group cutout unit 670 notifies the electric wire area generation unit 650 that all the laser data JDLai has been read in the electric wire solid space area (S92b).

    Next, when the electric wire region generation unit 650 is informed that all the laser data JDLai has been read into the electric wire solid space region from the electric wire region point group cutting unit 670, the three-dimensional position in addition to the three-dimensional position Pnai ′ + 1. It is determined whether there is Pnai ′ + 2 (S93).

  If it is determined in step S93 that there is a three-dimensional position Pnai ′ + 1 in addition to the three-dimensional position Pnai ′ + 1, the three-dimensional position Pnai ′ is updated to the three-dimensional position Pnai ′ + 1, and the three-dimensional position Pnai ′ + 1. Is updated to the three-dimensional position Pnai ′ + 2 and the process returns to step S85 in FIG. 10 to newly generate the wire solid space region JDBi by connecting the memory 680 (S94).

  The laser ortho image unit 70 reads the laser data JDLai in the wire solid space area stored in the wire solid space area JDBi, and the display image memory 70 corresponds to the reflection intensity of the laser data JDLai in the wire solid space area. The above-mentioned original image GDi is generated by assigning a gray scale value (see FIG. 15).

  More specifically, the laser ortho image generation unit 90 designates the pixel Gpi of the display image memory 70 and designates an area corresponding to the pixel Gpi on the uppermost surface (XY plane) of the wire solid space area JDBi. The number of pixels gDmi constituting this area is obtained, and the total reflection intensity of each of the laser data existing on gDmi (uppermost surface (XY plane) to lowermost surface (XY)) is obtained, The total value is averaged by the number, and a gray scale value corresponding to the average value is assigned (written) to the pixel Gpi of the image memory 70 for display. Then, the image output unit 80 displays the laser orthophoto image Rgbi on the screen.

  The description of FIG. 15 will be made with reference to FIG. FIG. 16 is a laser orthoimage including a road surface. FIG. 15 is a laser orthoimage (output range Di) of the electric wire solid space region at the height of Zss1 from the road surface.

   As shown in FIG. 15, the features (electric wires, tree crowns,...) In the electric wire three-dimensional space region are extracted.

  That is, since only the electric wire and the upper part of the tree hung on the telephone pole on the road are displayed as the laser ortho image GRgai, for example, when the height is the electric wire separation distance (predetermined height from the road surface; height ensuring safety) Since only the electric wires that are longer than the electric wire separation distance are displayed as an ortho image, it is possible to easily visually determine whether there is an area with dangerous electric wires.

  Here, generation of a laser ortho image including a road surface will be described.

<Embodiment 2>
In order to generate a laser ortho image including a road surface, the search vertical range of the road surface point search parameter in the memory 620 is set, for example, from the point h0 on the road surface as 1 m below 1 h and 1 m above 1 h (collectively this search). Preferably, the vertical range is referred to as hi). The reason for such a search vertical range hi is that the road is raised at the center and has a GPS error of about 1 m in the vertical direction. When the height hi is 1 m, the lower part is defined as 20 cm and the upper part is defined as 80 cm. Moreover, it may be 50 cm.

  Accordingly, the road surface point determination unit 610 and the electric wire region determination unit 650 under the movement trajectory generate a road three-dimensional space region of the road width Wi with reference to the point ho on the road surface in the memory 680 as shown in FIG. The inner point group extraction unit 670 reads the laser data in the road space area from the memory 30.

  Then, the laser orthoimage creating unit 90 generates and displays a laser orthophoto image of the road viewed from above as described above (see FIG. 18).

<Embodiment 3>
The above-mentioned original image may be provided with the low resolution image hierarchizing unit 220 as follows.

    FIG. 19 is a schematic configuration diagram of the on-road feature image generating apparatus when a low-resolution hierarchizing unit is provided. The low-resolution image hierarchization unit 220 includes a plurality of types of low-resolution calculation units 110, a hierarchical memory reservation unit 120, a corresponding original image pixel region determination unit 140, a pixel count calculation unit 150 with intra-region reflection intensity, The apparatus includes a reflection intensity calculation unit 160, a low-resolution laser ortho image creation unit 170, an original image update unit 200, and the like.

In this embodiment, a laser ortho image including a road surface will be described as an original image. FIG. 20 is a flowchart illustrating an on-road feature image generating apparatus provided with a low resolution layering unit.

  The operation of each part of the low resolution image hierarchizing unit 220 will be described with reference to the flowchart of FIG.

  The original image GDi generated in the display image image memory 80 is an n × m pixel group, and a gray scale value corresponding to the reflection intensity of the laser data is assigned to these pixels gDpi. The multiple types of low resolution calculation unit 110 calculates the resolution gi of the original image GDi every time a low resolution image generation instruction is input by the operator (S1). For example, the resolution gi of the original image GDi in the display image memory 80 is 1 cm resolution (for example, n × m: 8000 × 6000).

Then, the image size gki is notified to the hierarchical memory securing unit 120,
The hierarchical memory securing unit 120 secures the low resolution image memory area (130a, 130b,...: 130i) of the image size gki from the multiple types of low resolution calculating unit 110 in the hierarchical image memory unit 130 (FIG. 20). S2).

  That is, the multiple types of low resolution calculation unit 110 secures a low resolution image memory area whose width and height are 1 / K of the original image.

  The corresponding source image pixel area determination unit 140 generates a pixel Pgi (s, t) in the low resolution memory area every time a low resolution memory area (130a, 130b,...) Is generated in the hierarchical image memory reservation unit 120. The pixel area Gpi of the original image GDi in the display image memory 70 corresponding to is sequentially determined (S3 in FIG. 20: see FIG. 21).

  The number-of-regions-with-reflection-intensity pixel count calculation unit 150 generates a low-resolution image-by-region reflection intensity calculation result table 180i (1/2 low resolution, 1/4 low resolution,.・) Is generated.

  Then, the number Ni of reflection-intensity (grayscale value) pixels gDpi included in the determined pixel area Gpi of the original image GDi is calculated by a counter (not shown), and this is calculated as a reflection intensity calculation result for each low-resolution image. This is stored in the table 180i (see FIG. 22). At this time, the pixel gDpi without reflection intensity (grayscale value: “0”) is not counted (S4 in FIG. 20).

The reflection intensity calculation unit 160 for each area reads the grayscale value si of the pixel gDpi in the pixel area Gpi of the original image GDi determined by the corresponding original image pixel area determination unit 140 as the reflection intensity Ini, and sums each reflection intensity (ΣIn )

Then, the total reflection intensity (ΣIn) is divided by the count value Pki corresponding to the pixel area Gpi of the original image GDi, and this is calculated as the reflection intensity GPIni of the pixel Pgi of the low-resolution image memory area 130i (S5a in FIG. 20). The low resolution reflection intensity calculation result table 180i is stored (S5b in FIG. 20).

Next, the reflection intensity calculation unit for each area 160 determines whether or not the reflection intensity GPIni of all the pixels Pgi in the image memory area for low resolution 130i has been obtained. If not, the pixel Pgi is updated and the process proceeds to S4. Return (S6 in FIG. 20) When the low-resolution laser ortho-image creating unit 170 calculates the reflection intensity based on the original image for all Pgi in the display image memory 130, the low-resolution image-specific reflection intensity calculation of the low-resolution image is performed. The result table 180i is allocated, and the reflection intensity PGIini (grayscale value) linked to the pixel Pgi (s, t) of the corresponding low-resolution image memory area 130i (130a or 130b,. An image TRgi is created (S7 in FIG. 20).

   In the present embodiment, the low-resolution image TRgi includes, for example, a low-resolution laser orthophoto image TRgai for electric wires, a low-resolution laser orthophoto image TRgbi for road surfaces, and the like.

The original image update unit 200 monitors the low-resolution image memory unit 130 and determines whether or not a low-resolution image TRgi is newly created (S8 in FIG. 20). The low-resolution image TRgi is stored in the low-resolution image memory unit 130. If generated, it is read out and the original image GDi in the display image memory 80 is updated to this low resolution image TRgbi (S9a in FIG. 20).

The image output unit 80 displays the original image in the display image memory 70 (S9b).

The image selection unit 190 selects the low-resolution image TRgi designated by the operator from the hierarchical image memory unit 130, stores it in the display image memory 70, and causes the image output unit 80 to display it.

  FIG. 23 is an explanatory view of a laser orthophoto image RGbi for a road surface in a normal process that does not use the low resolution image layering unit 220, and shows an original image DGi having a 1 cm resolution.

  FIG. 24 is an explanatory diagram when the 1 cm resolution road region laser orthophoto image RGbi of FIG. 23 is converted to 5 cm resolution by the low resolution image layering unit.

  When FIG. 23 is compared with FIG. 24, FIG. 24 is generally brighter and the braille block at the top of the image can be easily identified.

  That is, the low resolution image hierarchization unit 220 according to the present embodiment applies a reflection intensity (reduction intensity (p) to the pixel gDpi constituting the pixel region Gpi of the original image corresponding to the pixel Pgi of the low resolution laser orthophoto image TRgbi for road surface with 5 cm resolution. When there is a pixel gDpi whose gray scale value is “0”, the number of pixels gDpi having no reflection intensity (gray scale value) is subtracted, and by this subtraction value, the pixel region Gpi of the original image corresponding to the pixel Pgi is subtracted. The total reflection intensity is divided (averaged), and this value is assigned (written) to the pixel Pgi in the image memory area of 5 cm resolution to create a low-resolution image TRgi.

  For this reason, as shown in FIG. 24, the overall image is bright, and the braille block at the top of the image is also easy to distinguish.

  That is, when the processing of the present embodiment is used, there is no deterioration even if the output range Di is wide.

  In addition, although it demonstrated as a road in the said embodiment, it may be a track.

  In addition, every time a laser ortho image is generated in the image memory, it may be stored in this video memory, and a desired laser ortho output range Di may be displayed or printed at a later date.

  In addition, although it demonstrated as a road in the said embodiment, it may be a track.

  In addition, every time a laser ortho image is generated in the image memory, it may be stored in this video memory, and a desired laser ortho output range Di may be displayed or printed at a later date.

The three-dimensional space area in the above embodiment may be displayed by color according to the height from the road surface.

DESCRIPTION OF SYMBOLS 10 Database 20 Output range laser data extraction part 40 Laser data display part 60 Cut out solid production | generation / Point cloud reading part 70 Display image memory 80 Image output part 90 Laser ortho image creation part 130 Image memory part 220 Low-resolution image hierarchization part

Claims (8)

A GPS receiver and a high-density laser device are mounted on the vehicle, and a laser is emitted at intervals of several centimeters while traveling from the high-density laser device to the target range while traveling on the road, and the obtained high-density laser data ( On the road where a laser orthophoto image of the three-dimensional space region (JDBi) is obtained on the display unit within a predetermined height range from the road surface of the vehicle based on the laser data (DLi) of the output range (Di) of the point cloud of Li) A feature image generation method comprising:
An image memory for display,
First storage means for storing a point cloud of laser data (DLi) in the output range (Di);
Second storage means for storing a three-dimensional position (Pni) of the GPS receiver constituting a movement locus (Pi) of the GPS receiver;
The search lower limit value (hs1) longer than the length (Hai) from the three-dimensional position (Pni) of the GPS receiver to the plane of the travel path and the laser point group below the three-dimensional position (Pni) are not searched. A third space that stores the three-dimensional space region formation information including a search unnecessary length (hs2: hs2 ≧ hs1) for determining the range and a predetermined height (hss1) from the surface of the traveling road to the three-dimensional space region (JDBi). Storage means;
A fourth storage means for generating a search area (Ci) for determining laser data (CLpai) of the surface of the traveling path immediately below the three-dimensional position (Pni) of the GPS receiver;
Fifth storage means for generating the three-dimensional space area (JDBi);
Prepare
Computer
(A1). Sequentially reading out the three-dimensional position (Pni) of the GPS receiver within the output range (Di) from the second storage means and sequentially defining it in the fourth storage means;
(A2). A perpendicular line (Pzi) is defined for each of the three-dimensional positions (Pni) defined in the fourth storage means, and a cylinder having a radius (Ri) is removed from the perpendicular line (Pzi) without the search unnecessary length (hs2). Generating the search area (Ci) of height length Chi (Chi = hs1-hs2) in the fourth storage means;
(A3). For each search area (Ci), the laser data (DLi) having the three-dimensional coordinates in the search area (Ci) is read from the storage means 1, and the laser data (in the search area (Ci)) ( Storing as CLi);
(A4). For each search area (Ci), a point group other than the road surface is removed from the point group of the laser data (CLi) stored in the search area (Ci), and the vertical line (Pzi) Determining nearby laser data as the laser data (CLpai) immediately below the three-dimensional position (Pni);
(A5). Each time the three-dimensional position (Pni) is defined in the fourth storage means, the laser data (CLpai) immediately below having the two-dimensional coordinates (x, y) of the three-dimensional position (Pni) is searched. , Updating the three-dimensional position (Pni) to the searched laser data (CLpai) immediately below, and defining it as the three-dimensional position (Pni ′) in the fifth storage means;
(A6). Between the three-dimensional position (Pni ′) defined in the fifth storage means and the next three-dimensional position (Pni ′ + 1), a predetermined height of the three-dimensional space region formation information of the third storage means Forming the three-dimensional space region (JDBi) at (hss1);
(A7). The laser data ((DLi)) having the three-dimensional position (Pin ′) in the three-dimensional space area (JDBi) generated in the fifth storage means is read from the first storage means, and this is read into the three-dimensional space. Storing the laser data (JDLai) in the region (JDBi) in the three-dimensional space region (JDBi);
(A8). Pixels (Gpi) of the image memory for display are sequentially designated, and for each designation, a region corresponding to the pixel (Gpi) is retrieved from the three-dimensional space region (JDBi), and laser data in the retrieved region is obtained. A step of calculating an average of the reflection intensity of (JDLai);
(A9). And obtaining a laser orthophoto image (RGai) by writing a grayscale value corresponding to the average value to a pixel (Gpi) of the display image memory. Generation method. The three-dimensional space region formation information includes the height (hss1) to the lower end of the three-dimensional space region (JDBi), the height (hss2) from the surface of the travel path to the upper end of the three-dimensional space region (JDBi), and the three-dimensional space. Width (Wi) of the spatial region (JDBi),
The step (A6)
The thickness (DBHi), which is the difference between the height (hss1) to the lower end of the three-dimensional space region (JDBi) and the height (hss2) from the surface of the travel path to the upper end of the three-dimensional space region (JDBi), 2. The on-road feature image generation method according to claim 1, wherein the three-dimensional space region (JDBi) is generated with the width (Wi). The computer is
(A10). Displaying a screen for inputting the three-dimensional space region formation information on the display unit;
(A11). The method according to claim 1 or 2, further comprising: storing the input three-dimensional space region formation information in the third storage unit. Preparing a low-resolution image memory for generating the low-resolution image (TRgi);
Computer
(B1). The laser orthophoto image as an original image (GDi), and calculating the resolution (vertical n pixels × horizontal m pixels) of the original image (GDi);
(B2). Calculating a predetermined low resolution with respect to the calculated resolution of the original image (GDi);
(B3). Defining the image memory for the low resolution at the calculated low resolution;
(B4). Sequentially specifying pixels (Pgi) defined in the image memory for low resolution and sequentially determining a pixel area (Gpi) of the original image (GDi) corresponding to the pixels (Pgi);
(B5). Each time the pixel area (Gpi) of the original image (GDi) is determined, a value “0” corresponding to the reflection intensity is assigned to one of the pixels (gDpi) constituting the pixel area (Gpi). If it is, the step of counting (Pki) the number of pixels (gDpi) constituting the pixel area (Gpi) of the determined original image (GDi), excluding the pixel (gDpi);
(B6). Each time the pixel area (Gpi) of the original image (GDi) is determined, a total value of values corresponding to the reflection intensity of the pixels (gDpi) constituting the pixel area (Gpi) is obtained, and this total value is calculated. Calculating an average value averaged by the count (Pki);
(B7). Each time the average value for the pixel region (Gpi) of the original image (GDi) is determined, the average value is reflected to the pixel (Pgi) of the designated image memory for low resolution. 4. The feature image on the road according to claim 1, further comprising: generating the low resolution image (TRgi) by allocating the image value according to intensity. Generation method.   5. The on-road feature image generation method according to claim 1, wherein the original image has a resolution of 5 cm or less.   5. The low-resolution image generation method according to claim 3, wherein the three-dimensional space area is an area of an artificial object or a tree branch provided on the periphery of the traveling road. A high-density laser data obtained by launching a laser at intervals of several centimeters while scanning from the high-density laser device to the target area while mounting a GPS receiver and high-density laser device on the vehicle. Travel that obtains a laser orthophoto image of a three-dimensional space region (JDBi) on a display unit within a predetermined height range from the travel road surface of the vehicle based on laser data (DLi) of an output range (Di) of a point group of (Li) A road feature image generation program,
An image memory for display,
First storage means for storing a point cloud of laser data (DLi) in the output range (Di);
Second storage means for storing a three-dimensional position (Pni) of the GPS receiver constituting a movement locus (Pi) of the GPS receiver;
The search lower limit value (hs1) longer than the length (Hai) from the three-dimensional position (Pni) of the GPS receiver to the plane of the travel path and the laser point group below the three-dimensional position (Pni) are not searched. A third space that stores the three-dimensional space region formation information including a search unnecessary length (hs2: hs2 ≧ hs1) for determining the range and a predetermined height (hss1) from the surface of the traveling road to the three-dimensional space region (JDBi). Storage means;
A fourth storage means for generating a search area (Ci) for determining laser data (CLpai) of the surface of the traveling path immediately below the three-dimensional position (Pni) of the GPS receiver;
Using the fifth storage means in which the three-dimensional space region (JDBi) is generated,
Computer
(C1). Means for sequentially reading out the three-dimensional position (Pni) of the GPS receiver within the output range (Di) from the second storage means and sequentially defining it in the fourth storage means;
(C2). A perpendicular line (Pzi) is defined for each of the three-dimensional positions (Pni) defined in the fourth storage means, and a cylinder having a radius (Ri) is removed from the perpendicular line (Pzi) without the search unnecessary length (hs2). Means for generating said search area (Ci) of height length Chi (Chi = hs1-hs2) in said fourth storage means;
(C3). For each search area (Ci), the laser data (DLi) having the three-dimensional coordinates in the search area (Ci) is read from the storage means 1, and the laser data (in the search area (Ci)) ( Means for storing as CLi),
(C4). For each search area (Ci), a point group other than the road surface is removed from the point group of the laser data (CLi) stored in the search area (Ci), and the vertical line (Pzi) Means for determining nearby laser data as the laser data (CLpai) immediately below the three-dimensional position (Pni);
(C5). Each time the three-dimensional position (Pni) is defined in the fourth storage means, the laser data (CLpai) immediately below having the two-dimensional coordinates (x, y) of the three-dimensional position (Pni) is searched. The three-dimensional position (Pni) is updated to the searched laser data (CLpai) immediately below, and defined as the three-dimensional position (Pni ′) in the fifth storage means,
(C6). Between the three-dimensional position (Pni ′) defined in the fifth storage means and the next three-dimensional position (Pni ′ + 1), a predetermined height of the three-dimensional space region formation information of the third storage means Means for forming the three-dimensional space region (JDBi) at (hss1);
(C7). The laser data ((DLi)) having the three-dimensional position (Pin ′) in the three-dimensional space area (JDBi) generated in the fifth storage means is read from the first storage means, and this is read into the three-dimensional space. Means for storing the laser data (JDLai) in the region (JDBi) in the three-dimensional space region (JDBi);
(C8). Pixels (Gpi) of the image memory for display are sequentially designated, and for each designation, a region corresponding to the pixel (Gpi) is retrieved from the three-dimensional space region (JDBi), and laser data in the retrieved region is obtained. Means for calculating the average of the reflection intensity of (JDLai);
(C9). A feature image on the road for executing a function as means for obtaining the laser orthophoto image (RGai) by writing a gray scale value corresponding to the average value to the pixel (Gpi) of the image memory for display. Generation program. A high-density laser data obtained by launching a laser at intervals of several centimeters while scanning from the high-density laser device to the target area while mounting a GPS receiver and high-density laser device on the vehicle. Travel that obtains a laser orthophoto image of a three-dimensional space region (JDBi) on a display unit within a predetermined height range from the travel road surface of the vehicle based on laser data (DLi) of an output range (Di) of a point group of (Li) A road feature image generating device,
An image memory for display,
First storage means for storing a point cloud of laser data (DLi) in the output range (Di);
Second storage means for storing a three-dimensional position (Pni) of the GPS receiver constituting a movement locus (Pi) of the GPS receiver;
The search lower limit value (hs1) longer than the length (Hai) from the three-dimensional position (Pni) of the GPS receiver to the plane of the travel path and the laser point group below the three-dimensional position (Pni) are not searched. A third space that stores the three-dimensional space region formation information including a search unnecessary length (hs2: hs2 ≧ hs1) for determining the range and a predetermined height (hss1) from the surface of the traveling road to the three-dimensional space region (JDBi). Storage means;
A fourth storage means for generating a search area (Ci) for determining laser data (CLpai) of the surface of the traveling path immediately below the three-dimensional position (Pni) of the GPS receiver;
Fifth storage means for generating the three-dimensional space area (JDBi);
(D1). Means for sequentially reading out the three-dimensional position (Pni) of the GPS receiver within the output range (Di) from the second storage means (50) and sequentially defining it in the fourth storage means; ,
(D2). A perpendicular line (Pzi) is defined for each of the three-dimensional positions (Pni) defined in the fourth storage means, and a cylinder having a radius (Ri) is removed from the perpendicular line (Pzi) without the search unnecessary length (hs2). Means for generating the search area (Ci) of height length Chi (Chi = hs1-hs2) in the fourth storage means;
(D3). For each search area (Ci), the laser data (DLi) having the three-dimensional coordinates in the search area (Ci) is read from the storage means 1, and the laser data (in the search area (Ci)) ( Means for storing as CLi);
(D4). For each search area (Ci), a point group other than the road surface is removed from the point group of the laser data (CLi) stored in the search area (Ci), and the vertical line (Pzi) Means for determining nearby laser data as the laser data (CLpai) immediately below the three-dimensional position (Pni);
(D5). Each time the three-dimensional position (Pni) is defined in the fourth storage means, the laser data (CLpai) immediately below having the two-dimensional coordinates (x, y) of the three-dimensional position (Pni) is searched. Updating the three-dimensional position (Pni) to the searched laser data (CLpai) immediately below, and defining it as the three-dimensional position (Pni ′) in the fifth storage means;
(D6). Between the three-dimensional position (Pni ′) defined in the fifth storage means and the next three-dimensional position (Pni ′ + 1), a predetermined height of the three-dimensional space region formation information of the third storage means Means for forming the three-dimensional space region (JDBi) at (hss1);
(D7). The laser data ((DLi)) having the three-dimensional position (Pin ′) in the three-dimensional space area (JDBi) generated in the fifth storage means is read from the first storage means, and this is read into the three-dimensional space. Means for storing in the three-dimensional space area (JDBi) as laser data (JDLai) in the area (JDBi);
(D8). Pixels (Gpi) of the image memory for display are sequentially designated, and for each designation, a region corresponding to the pixel (Gpi) is retrieved from the three-dimensional space region (JDBi), and laser data in the retrieved region is obtained. Means for obtaining an average of the reflection intensity of (JDLai);
(D9). And a means for obtaining the laser orthophoto image (RGai) by writing a gray scale value corresponding to the average value to a pixel (Gpi) of the image memory for display. Generator.