JP6689793B2 - Map data generation device, method, and program - Google Patents

Description

  The present invention relates to a map data generation device, method, and program.

  Conventionally, a technique for simplifying polygons included in map data has been proposed (for example, see Patent Document 1). In this technique, a polygon is simplified by short-circuiting a part of the outline with an extended line segment obtained by extending a line segment of the outline forming the polygon.

JP, 2005-283867, A

By the way, the technique of simplifying the polygon described above is effective for map data in which various features such as a topographic map are arranged on a single plane. However, recent map data has, for example, the following two features.
Feature 1: The features are grouped by type of feature (eg, road, building, etc.), and each feature included in the map data is given a “layer ID” indicating the type of feature.
Feature 2: Not only graphic data representing the shape of the feature but also attribute information associated with the feature such as the name of the store and the business hours is added to the feature.

  When map distribution and map drawing are performed using map data with an increased amount of information in this way, the amount of communication increases and the processing load on the terminal that draws the map increases, and user convenience decreases. There was a problem. In order to solve this problem, it is conceivable to reduce the amount of map data, but the conventional technique cannot solve this problem as follows.

  Due to the above feature 1, when a plurality of types of features are displayed at the same time, it is conceivable to display one feature as an upper face and the other feature as a lower face for overlapping features as a result of overlapping. However, as a result of this, since the graphic data of the hidden portion is also included in the map data, useless communication volume and drawing processing occur.

  Further, due to the above-mentioned feature 1, the feature data of a type unnecessary for a specific request and service is also included in the map data, resulting in a wasteful communication amount. Further, due to the characteristic 2, even if the feature data of a type required for a specific request and service is included in the feature data, attribute data unnecessary for the request and service is included in the feature data. The amount will be generated.

  Further, due to the above-mentioned feature 1, the same features such as furniture in an apartment building and indoor columns may be arranged under a certain regularity (eg, arranged at regular intervals in an underground passage). Pillars). For example, when there are a large number of pillars, a large amount of the same feature is included in the map data, resulting in unnecessary communication volume and drawing processing.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a map data generation device, method, and program capable of reducing the data amount of map data to be output.

  In order to achieve the above-mentioned object, a map data generation device according to a first aspect of the present invention is feature data including a layer ID corresponding to a feature type and graphic information indicating the shape of a feature and a position in a map. And the graphic information hidden by the graphic information of the feature data of the layer ID on the front side on the basis of an acquisition unit that acquires map data including each feature and a predetermined overlay order for each layer ID. It is configured to include a reduction unit that deletes the feature data from the map data, and an output unit that outputs the map data obtained by the reduction unit.

  A map data generating method according to a second aspect of the present invention is map data including feature data including a layer ID corresponding to a feature type and graphic information indicating a feature shape and a position in a map, for each feature. And delete the feature data including the graphic information hidden by the graphic information of the feature data of the layer ID on the front side from the map data, based on the predetermined stacking order for each layer ID. , Output the map data that has undergone the process of deleting.

  According to the first invention and the second invention, the data amount of the map data to be output can be reduced by deleting the data regarding the feature hidden by the feature displayed on the front side.

  A map data generation device according to a third aspect of the present invention obtains map data including feature data including a layer ID corresponding to a feature type and attribute information including an attribute name and an attribute value for each feature. From the map data, at least one of a part, feature data of a specified layer ID, feature data having a combination of a specified attribute name and attribute value, and attribute information including a specified attribute name It includes a reduction unit to be deleted and an output unit that outputs the map data obtained by the reduction unit.

  In the map data generating method according to the fourth aspect, the acquisition unit includes map data including feature data including a layer ID corresponding to a feature type and attribute information including an attribute name and an attribute value for each feature. And the reduction unit acquires at least one of the feature data having the specified layer ID, the feature data having a combination of the specified attribute name and the attribute value, and the attribute information including the specified attribute name. Is deleted from the map data, and the output unit outputs the map data that has undergone the deleting process.

  According to the third and fourth inventions, the feature data having the specified layer ID, the feature data having the combination of the specified attribute name and the attribute value, and the attribute information including the specified attribute name. By deleting at least one of the above, it is possible to reduce the data amount of the map data to be output.

  A map data generation device according to a fifth aspect of the present invention is map data including feature data including a layer ID corresponding to a feature type and graphic information indicating a shape of a feature and a position in a map for each feature. And an identifying unit that identifies, for each layer ID, a feature that is repeatedly arranged with a predetermined regularity, and a feature that is repeatedly arranged that is identified by the identifying unit. The reduction unit that replaces the graphic information of the feature data with information indicating the shape of the feature and the regularity, or deletes the feature data of the repeatedly arranged features from the map data, and the reduction unit. And an output unit for outputting the obtained map data.

  In the map data generation method according to a sixth aspect, the acquisition unit obtains the feature data including a layer ID corresponding to the feature type and graphic information indicating the shape of the feature and the position in the map, and the feature data. , The specifying unit specifies, for each layer ID, the features repeatedly arranged with a predetermined regularity, and the reducing unit specifies the repeatedly arranged places. The graphic information of the feature data of the object is replaced with information indicating the shape of the feature and the regularity, or the feature data of the repeatedly arranged features is deleted from the map data and replaced by the output unit. The map data that has been processed or deleted is output.

  According to the fifth invention and the sixth invention, the graphic information of the feature data of the repeatedly arranged features is replaced with information representing the shape and regularity of the feature, or the feature information is output. The amount of map data can be reduced.

  Further, the program of the present invention is a program for causing a computer to function as each unit of the above map data generation device.

  As described above, according to the map data generating device, method, and program of the present invention, it is possible to reduce the amount of map data to be output.

It is a block diagram of the map data generation device concerning a 1st embodiment. It is a figure which shows an example of the map data for input which concerns on each embodiment. It is a figure which shows an example of the display hierarchy setting data which concerns on each embodiment. It is a flow chart which shows a processing routine of map data generation processing concerning a 1st embodiment. It is a figure which shows an example of the mask figure which concerns on each embodiment. It is a figure which shows an example of the map data for distribution which concerns on 1st Embodiment. It is a figure for demonstrating the process which deletes a passable area. 9 is a flowchart showing a processing routine of replacement processing according to a modification of the first embodiment. It is a figure for demonstrating the replacement process of figure information. It is a block diagram of a map data generation device according to a second embodiment. It is a figure which shows an example of the feature deletion condition data which concerns on 2nd and 3rd embodiment. It is a figure which shows an example of the attribute deletion condition data which concerns on 2nd and 3rd embodiment. It is a flow chart which shows a processing routine of map data generation processing concerning a 2nd embodiment. It is a figure which shows an example of the map data for distribution which concerns on 2nd Embodiment. It is a block diagram of a map data generation device concerning a 3rd embodiment. It is a figure for demonstrating the process which detects a line segment. It is a figure for demonstrating the process which repeatedly specifies a feature. It is a figure for demonstrating the process which repeatedly specifies a feature. It is a figure for demonstrating repetition pattern information. It is a flow chart which shows a processing routine of map data generation processing concerning a 3rd embodiment. It is a figure for demonstrating reduction of the amount of data by repeatedly putting together a feature. It is a figure for demonstrating the process which replaces a repeated feature with an image.

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

<First Embodiment>
<Configuration of map data generation device>
The configuration of the map data generation device according to the first embodiment will be described. The map data generation device 10 according to the present embodiment can be configured by a computer including a CPU, a RAM, and a ROM that stores a program for executing a processing routine described later and various data. The map data generation device 10 functionally includes an acquisition unit 12, a reduction unit 14, and an output unit 16 as illustrated in FIG. 1. Further, input map data 20 and display hierarchy setting data 22 are stored in a predetermined storage area of the map data generating device 10.

  FIG. 2 shows an example of the map data 20. As shown in FIG. 2, the map data 20 includes a number for identifying a feature, a layer ID corresponding to the feature type, graphic information indicating the shape of the feature and a position in the map, and a feature. Feature data including attribute information indicating information associated with the feature is included for each feature. For example, when the shape of the feature is a polygon, the coordinate of each vertex of the polygon is stored in the graphic information sequence. Moreover, in the example of FIG. 2, the creator who created the feature data and the sharing status of the feature data are stored as the attribute information, but the attribute information is not limited to this. Information representing other attributes associated with the feature may be stored as the attribute information.

  Further, FIG. 3 shows an example of the display hierarchy setting data 22. As shown in FIG. 3, the display layer setting data 22 includes a predetermined stacking order for each layer ID. In the present embodiment, when a map is displayed on the display device in accordance with the map data 20, features of a type having a small overlay order are overlaid on top of features of a large overlay order (that is, , On the front side) is displayed. That is, for example, when at least a part of the areas of the pillar and the floor overlap, the area of the floor that overlaps the pillar is hidden by the corresponding area of the pillar.

  The acquisition unit 12 acquires the map data 20. The map data 20 may be stored in an external device, and the acquisition unit 12 may acquire the map data 20 from the external device via the network. The reduction unit 14 hides the feature data of the map data 20 acquired by the acquisition unit 12 based on the overlapping order of the display layer setting data 22 by the graphic information of the feature data of the layer ID on the front side. Delete the feature data including.

  The output unit 16 outputs the map data 20 processed by the reduction unit 14 as map data 24 for distribution. The output unit 16 may output the map data 24 to a non-volatile storage unit or may output (transmit) it to another device via a network.

<Operation of map data generation device>
Next, the operation of the map data generation device 10 according to this embodiment will be described. When a map data distribution request is input to the map data generation device 10 from another device, the map data generation device 10 executes the map data generation processing routine shown in FIG.

  In step S10, the acquisition unit 12 acquires the map data 20. In step S12, the reduction unit 14 substitutes 1 into the variable i for the counter as initialization processing to generate empty mask graphic data. In step S14, the reduction unit 14 refers to the display layer setting data 22 and acquires the layer ID whose superposition order is i. Then, the reduction unit 14 refers to the map data 20 acquired in step S10, and combines the mask graphic for masking the graphic of the feature corresponding to the acquired layer ID with the mask graphic indicated by the mask graphic data. In addition, when the map data 20 has a plurality of features corresponding to the acquired layer ID, the reduction unit 14 indicates a mask figure indicated by the mask figure data, which is a mask figure combining mask figures for masking each of the plurality of features. Bind to.

  In step S16, the reduction unit 14 refers to the display layer setting data 22 and acquires the layer ID whose superposition order is (i + 1). Then, the reduction unit 14 is the feature of the layer ID acquired from the map data 20 acquired in step S10 based on the mask graphic data generated in the immediately preceding step S14, and all of the feature. The feature whose area is included in the mask graphic indicated by the mask graphic data is deleted.

  In step S18, the reduction unit 14 determines whether or not the value of the variable i is the maximum value −1 of the superposition order of the display hierarchy setting data 22. If this determination is negative, the process proceeds to step S20. In step S20, the reduction unit 14 adds 1 to the value of the variable i. When the process of step S20 ends, the process returns to step S14.

  Here, with reference to FIG. 5, the mask graphic indicated by the mask graphic data immediately before step S14 when the value of the variable i is 1 to 3 will be described. As shown on the left side of FIG. 5, when the variable i is 1, the mask graphic data does not exist because the mask graphic data is initialized to empty immediately before step S14. Next, in step S14, a mask figure that masks the pillars having the superposition order of 1 is generated. Further, in step S16, since the feature of the floor whose superposition order is i + 1 = 2 is not included in the mask graphic, the feature of the floor is not deleted. Then, the variable i becomes 2 in step S20, and the process returns to step S14. That is, as shown in the central portion of FIG. 5, when the variable i is 2, a mask figure for masking the pillar is generated immediately before step S14.

  Next, in step S14, a mask figure in which the mask figure for masking the floor whose superposition order is 2 is combined with the mask figure for masking the pillar generated in the previous step S14 is generated. Further, in step S16, since the features in the passable area whose superposition order is i + 1 = 3 are not included in the mask graphic, the features in the passable area are not deleted. Then, the variable i becomes 3 in step S20, and the process returns to step S14. That is, as shown on the right side of FIG. 5, when the variable i is 3, a mask figure for masking the pillar and the floor is generated immediately before step S14.

  The above steps S14 to S20 are repeatedly executed until the determination of step S18 becomes affirmative.

  On the other hand, if the determination in step S18 is affirmative, the process proceeds to step S22. In step S22, the output unit 16 outputs the map data 20 that has undergone the above processing as the map data 24 for distribution. When the processing of step S22 ends, the map data generation processing routine ends.

  FIG. 6 shows an example of the map data 24. Note that, as shown in FIG. 7, the map data 20 shown in FIG. 2 includes the entire passable area having a stacking order of 3 included in the floor having a stacking order of 2, as shown in FIG. , The map data 24 when the feature data of the passable area with the number 5 is deleted. Further, in order to avoid complication, in FIG. 6, the deleted data is shown with a strikethrough line.

  As described above, according to the present embodiment, the data amount of map data to be distributed can be reduced by deleting the data related to the feature hidden by the feature displayed on the front side. Can be reduced. Further, it is possible to prevent wasteful drawing processing.

  In the first embodiment, the information amount of the graphic information of the non-hidden portion of the feature which is partially hidden by the feature displayed on the front side in the overlapping order is smaller than the information amount of the original graphic information. When the size is small, the original graphic information may be replaced with the graphic information of the non-hidden portion. In this embodiment, for example, the replacement processing routine shown in FIG. 8 is executed between step S16 and step S18 of the map data generation processing routine. It should be noted that this replacement processing routine is executed for each of the features having an area that partially overlaps the mask figure indicated by the mask figure data.

  In step S30, the reduction unit 14 uses the graphic information of the map data 20 to create a graphic in which a portion overlapping the mask graphic is removed. In step S32, the reduction unit 14 determines whether or not the number of vertices of the figure created in step S30 is smaller than the number of vertices of the original figure. If this determination is affirmative, the process proceeds to step S34.

  In step S34, the reduction unit 14 replaces the graphic information of the feature to be processed with the graphic information representing the graphic created in step S32. When the process of step S34 ends, the replacement process routine ends.

  On the other hand, if the determination in step S32 is negative, the process of step S34 is not executed and the replacement process routine ends. For example, in the example shown in FIG. 9, since the number of vertices (= 6) of the figure created by the process of step S30 is larger than the original number of vertices (= 4) of the feature to be processed, The determination of step S32 is negative, and the process of step S34 is not executed.

  In this form example, the graphic information can be reduced even for a part of the feature that is partially hidden, so that the amount of map data can be further reduced.

<Second Embodiment>
Next, a second embodiment will be described. In addition, about the part which becomes the same structure as 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

<Configuration of map data generation device>
As shown in FIG. 10, the map data generation device 110 according to the present embodiment is configured by a computer including a CPU, a RAM, and a ROM that stores a program for executing a processing routine described below and various data. can do. The map data generation device 110 functionally includes an acquisition unit 12, a reduction unit 114, and an output unit 16 as illustrated in FIG. 10. Further, input map data 20, display hierarchy setting data 22, feature deletion condition data 26, and attribute deletion condition data 28 are stored in a predetermined storage area of the map data generation device 110.

  FIG. 11 shows an example of the feature deletion condition data 26. As shown in FIG. 11, the feature deletion condition data 26 includes data indicating a condition for deleting the feature data from the map data 20. As shown in FIG. 11, in the present embodiment, the combination of the layer ID and the attribute name and attribute value in the attribute information is applied as the condition for deleting the feature data.

  FIG. 12 shows an example of the attribute deletion condition data 28. As shown in FIG. 12, the attribute deletion condition data 28 includes data indicating a condition for deleting the attribute information from the map data 20. As shown in FIG. 12, in the present embodiment, the attribute name is applied as the condition for deleting the attribute information.

  The reduction unit 114 has the following functions in addition to the functions of the reduction unit 14 according to the first embodiment. The reduction unit 114 according to the present embodiment refers to the feature deletion condition data 26 and deletes the feature data satisfying the deletion condition stored in the feature deletion condition data 26 from the map data 20. Further, the reduction unit 114 according to the present embodiment refers to the attribute deletion condition data 28, and deletes the attribute information stored in the attribute deletion condition data 28 that satisfies the deletion condition from the map data 20.

<Operation of map data generation device>
Next, the operation of the map data generation device 110 according to this embodiment will be described. When a map data distribution request is input to the map data generation device 110 from another device, the map data generation device 110 executes the map data generation processing routine shown in FIG. Note that steps in FIG. 13 that execute the same processing as in FIG. 4 are assigned the same step numbers as in FIG. 4, and description thereof is omitted.

  In step S11, the reduction unit 114 refers to the feature deletion condition data 26 and deletes the feature data satisfying the deletion condition stored in the feature deletion condition data 26 from the map data 20. In step S21, the reduction unit 114 refers to the attribute deletion condition data 28 and deletes the attribute information that satisfies the deletion condition stored in the attribute deletion condition data 28 from the map data 20.

  FIG. 14 shows an example of the map data 24. As shown in FIG. 14, according to the feature deletion condition data 26 shown in FIG. 11, by the process of step S11, the feature whose number “2” is included in the attribute information “Shared status” is “Stopped sharing” is 2 The data and the feature data having the layer ID “inaccessible area” and the number 3 are deleted from the map data 20. Further, as shown in FIG. 14, according to the attribute deletion condition data 28 shown in FIG. 12, the information having the attribute name “creator” is deleted from the attribute information of the map data 20 by the process of step S21.

  As described above, according to the present embodiment, the data amount of map data to be distributed can be reduced according to the designated deletion condition, and the communication amount can be reduced.

<Third Embodiment>
Next, a third embodiment will be described. In addition, about the part which becomes the same structure as 2nd Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

<Configuration of map data generation device>
As shown in FIG. 15, the map data generation device 210 according to the present embodiment is configured by a computer including a CPU, a RAM, and a ROM that stores a program for executing a processing routine described later and various data. can do. The map data generation device 210 functionally includes an acquisition unit 12, an identification unit 13, a reduction unit 214, and an output unit 16 as illustrated in FIG. 15. Further, in a predetermined storage area of the map data generation device 210, input map data 20, display hierarchy setting data 22, feature deletion condition data 26, and attribute deletion condition data 28 are stored.

  The identifying unit 13 identifies, from among the features included in the map data 20, features that are repeatedly arranged with a predetermined regularity for each layer ID (hereinafter, referred to as “repeating features”). To do. In the present embodiment, the identifying unit 13 repeatedly identifies, for each feature having the same layer ID, features that are arranged at equal intervals on the same straight line as a feature. Hereinafter, with reference to FIGS. 16 to 19, a process in which the specifying unit 13 repeatedly specifies a feature will be described.

First, as shown in FIG. 16, the identifying unit 13 performs a process of detecting a line segment for a set of feature positions included in the map data 20. In the present embodiment, the identifying unit 13 uses a known method such as Random Sample Consensus for detecting the line segment. Next, as shown in FIG. 17, the identifying unit 13 rotates the feature on the XY plane so that the detected line segment matches the X axis. Further, the specifying unit 13 randomly selects two points (p1 (x1, y1), p2 (x2, y2)) from the set of the position of the feature, and according to the following formulas (1) and (2), Calculate dx and dy.
dx = x1-x2 (1)
dy = y1-y2 (2)

Then, as shown in FIG. 18, the specifying unit 13 calculates a set (M) of features that matches P (nx, ny) defined by the following expression (3) in the set of positions of the features. Then, for the calculated feature set (M), the score S is calculated according to the following equation (4). Note that nx and ny in the formula (3) are integers. Further, the importance of the feature i in the expression (4) is a value calculated by the feature or attribute value (for example, size, height, etc.) of the feature. Also, size (M) in the equation (4) is the number of features included in the set (M).
P (nx, ny) = (x1 + nx × dx, y1 + ny × dy) (3)

  The specifying unit 13 performs a process of calculating the set (M) of features and the score S by making two points randomly selected different from each other and combining all two points in the set of positions of features included in the map data 20. For a set (M) having the maximum score S. Then, the specifying unit 13 repeatedly specifies, from the features included in the map data 20, the features that match the obtained set (M) as the repeated features. Further, as illustrated in FIG. 19, the specifying unit 13 determines the shape and position information of the top left feature of the feature identified as the repeated feature, the number of columns and rows of the repeated feature, and the repeated feature. The rotation angle and the repeating area are calculated as the repeating pattern information. That is, the repetitive pattern information includes information on the shape of one repetitive feature and the regularity of repetitive arrangement including position information. Note that, in FIG. 19, the feature repeatedly identified as the feature by the identifying unit is represented by a dashed circle.

  The reduction unit 214 has the following functions in addition to the functions of the reduction unit 114 according to the second embodiment. The reduction unit 214 according to the present embodiment collects the feature data of each repetitive feature specified by the specifying unit 13 in the map data 20 into one feature data and converts it into the graphic information of the one feature data. , Repeating pattern information of repeating features is stored.

<Operation of map data generation device>
Next, the operation of the map data generation device 210 according to this embodiment will be described. When a map data distribution request is input to the map data generation device 210 from another device, the map data generation device 210 executes the map data generation processing routine shown in FIG. Note that steps in FIG. 20 that execute the same processing as in FIG. 13 are assigned the same step numbers as in FIG. 13, and description thereof is omitted.

  In step S301, as described above, the identifying unit 13 identifies the repeating feature from the features included in the map data 20 and calculates the repeating pattern information of the identified repeating feature. In step S302, the reduction unit 214 puts together the feature data of each of the repeated features specified in step S301 in the map data 20 into one feature data, and adds the feature information of the one feature data to step S301. The repetitive pattern information calculated in step 3 is stored.

  As described above, according to the present embodiment, as shown in FIG. 21, each feature data item of the repeating feature of the input map data 20 is one feature item in the distribution map data 24. Since the data is collected, the amount of map data to be distributed can be reduced and the communication amount can be reduced.

  Note that, in the third embodiment, as shown in FIG. 22, information indicating the shape of a repeating feature in the map data 20 is predetermined for a feature such as an icon image representing the feature. It may be replaced with an image. Note that, as shown in the above formula (4), the lower the importance of the feature, the larger the score S. Then, the identifying unit 13 identifies, from the features included in the map data 20, the features that match the set (M) having the maximum score S as the repeated features, and thus the repeated features are important. The feature is relatively low. Therefore, the reduction unit 214 may delete the feature data of the repeated feature identified by the identification unit 13 in the map data 20.

  The present invention is not limited to the above-described embodiments, and various modifications and applications are possible without departing from the gist of the present invention.

  For example, although the case where the generated map data is distributed has been described as an example, the present invention is not limited to this, and the generated map data may be output for a purpose other than distribution.

  Further, although cases have been described with the above embodiment as examples where the functional units of the map data generation devices 10, 110, and 210 are realized by executing programs, the present invention is not limited to this. Each functional unit of the map data generation device 10, 110, 210 may be realized by hardware such as FPGA (Field-Programmable Gate Array), or may be realized by a combination of hardware and software.

  Further, in the specification of the present application, the embodiment in which the program is pre-installed has been described, but the program can be stored in a computer-readable recording medium and provided, or provided via a network. It is also possible to do so.

10, 110, 210 Map data generation device 12 Acquisition unit 13 Identification unit 14, 114, 214 Reduction unit 16 Output unit 20, 24 Map data 22 Display hierarchy setting data 26 Feature deletion condition data 28 Attribute deletion condition data

Claims (7)

An acquisition unit that acquires map data including feature data including layer IDs corresponding to the types of features and shape information of the features and graphic information indicating positions in the map, and each feature.
Based on a predetermined overlay order for each layer ID, and feature data including graphic information all hidden by the graphic information of the feature data of the front side of the layer ID, delete from the map data, the Regarding the graphic information part of which is hidden by the graphic information of the feature data of the layer ID on the front side, when the information amount of the graphic information of the non-hidden portion is smaller than the information amount of the original graphic information, the original graphic information And a reduction unit that replaces with the graphic information of the non-hidden portion ,
An output unit that outputs the map data obtained by the reduction unit,
A map data generation device including.   The graphic information is the coordinates of each vertex of the feature,
  The information amount of the graphic information is the number of vertices represented by the graphic information,
  For the graphic information part of which is hidden by the graphic information of the feature data of the layer ID on the front side, the reducing unit has a smaller number of vertices represented by the graphic information of the non-hidden portion than the number of vertices represented by the original graphic information. In this case, the original graphic information is replaced with the graphic information of the non-hidden portion.
  The map data generation device according to claim 1. An acquisition unit that acquires map data including feature data including layer IDs corresponding to the types of features and shape information of the features and graphic information indicating positions in the map, and each feature.
For each layer ID, a feature that is repeatedly arranged with a predetermined regularity and that coincides with a set having a maximum score that is calculated as a larger value as the importance of the feature is lower is repeated feature. A specific part that specifies as
The graphical information of the feature data of the Repetition rate land object identified by the identification unit, to replace the information representative of the shape and the regularity of the feature, or said feature data of the Repetition rate earth material A reduction unit that deletes from the map data,
An output unit that outputs the map data obtained by the reduction unit,
A map data generation device including. The reduction unit, the graphic information of the feature data of the Repetition rate land object specified by the specifying unit, after replacing the information representative of the shape and the regularity of features, the shape of the feature The map data generation device according to claim 3, wherein a predetermined image for the feature is replaced. The acquisition unit acquires the map data including the feature data including the layer ID corresponding to the feature type and the feature shape and the graphic information indicating the position in the map, for each feature,
From the map data, the reduction unit extracts feature data including graphic information that is completely hidden by the graphic information of the feature data of the layer ID on the front side, based on a predetermined stacking order for each layer ID. Regarding the graphic information which is deleted and is partially hidden by the graphic information of the feature data of the layer ID on the front side, when the information amount of the graphic information of the non-hidden portion is smaller than the information amount of the original graphic information, Replace the original graphic information with the non-hidden graphic information,
A map data generation method in which an output unit outputs map data that has undergone deletion processing and replacement processing . The acquisition unit acquires the map data including the feature data including the layer ID corresponding to the feature type and the feature shape and the graphic information indicating the position in the map, for each feature,
The specifying unit determines a feature that is repeatedly arranged for each layer ID with a predetermined regularity , and that matches a set with a maximum score that is calculated as a larger value as the importance of the feature is lower. , Repeatedly identified as a feature ,
The reduction unit, the graphic information of the feature data of the Repetition rate land was identified, or replaced with information representing the shape and the regularity of features, or the feature data of the Repetition rate earth material Delete from map data,
A map data generation method in which an output unit outputs map data that has undergone replacement processing or deletion processing.   A program for causing a computer to function as each unit of the map data generation device according to any one of claims 1 to 4.