Contour line contradiction inspection method and device

Abstract

The invention discloses a contour line contradiction inspection method and device, and solves the problems that manual inspection of contour lines is large in workload and low in efficiency, but automatic inspection generates more false alarms in the prior art. The contour line contradiction checking method comprises the following steps: acquiring a data set of a target area; diverging a number of search lines from the first contour line; determining a second contour line of which the number of intersection points with the search line is greater than a set threshold value in the contour lines initially encountered when the search line extends; determining the elevation difference between the first contour line and the second contour line according to the attribute data; and comparing the elevation difference with the equal altitude distance, and generating error reporting data according to a comparison result. According to the method and the device, the condition that a plurality of equal-height distances exist in one piece of data can be checked, in order to overcome the problems of low manual checking efficiency and large workload, the error report change rate is introduced, the error report amount is optimized, and the working efficiency and quality are improved.

Description

Technical Field

[0001] The present application relates to the technical field of computer data processing and geographic information database, and in particular to a method and device for checking contour line contradictions. Background Art

[0002] With the development of surveying and mapping technology, the surveying and mapping industry has gradually evolved from analog surveying and digital surveying to information-based surveying and even intelligent surveying, and topographic map results have also evolved from traditional paper topographic maps and electronic topographic maps to information-based topographic maps. Driven by application needs, the requirement for vector topographic maps is not just two-dimensional information, but three-dimensional information.

[0003] Ordinary maps with a scale greater than 1:1 million that focus on showing terrain are called topographic maps, which are projections of the surface undulation, geographical location, and shape onto a horizontal plane in the direction of the plumb line. The key element that can directly identify the surface undulation on a topographic map is the contour line. A specific contour interval (the height difference between adjacent contour lines) is generally used at a specific scale. The denser the contour lines (the smaller the spacing), the greater the surface undulation, and vice versa. Contour lines are used to identify topographic features such as peaks, valleys, and saddles. Therefore, whether the contour lines can be correctly expressed is crucial to truly reflecting the surface undulation.

[0004] Whether it is through the upgrading of traditional vector topographic maps or the acquisition of contour lines through information and intelligent surveying and mapping methods, due to the complex surface morphology, the diversity of attachments (vegetation, structures, etc.), the mapping method and timeliness, etc., there are often errors in graphics or attributes in the contour line results, especially the contradictions between the contour lines themselves and each other, which affect the true expression of the surface morphology. In domestic areas with large surface undulations, such as Sichuan, Chongqing, Yunnan and Guizhou, the more contour lines there are, the more likely errors will occur in the surveying and mapping process. It is difficult to accurately and efficiently discover problems by relying on the naked eye and ordinary attribute inspection, or by simple distance calculation, and it is difficult to achieve the purpose of accurate positioning and repair.

[0005] The recognition of incorrect expression of contour lines mainly involves searching and identifying the elevation difference between adjacent contour lines in the result map. In the map area with the set contour interval, the elevation difference between any adjacent contour lines should be the same, that is, equal to the contour interval. An error message is generated when it is found that the elevation difference is not equal to the contour interval. However, since the contour lines of the actual map are often not theoretically closed curves due to the influence of land objects, but often terminate or interrupt, the above changes in the contour line morphology do not necessarily mean that there are errors in the map. In the above situation, no matter which direction the automatic search is performed in, misjudgment may occur, such as judging non-adjacent contour lines as adjacent contour lines, or judging adjacent contour lines as non-adjacent contour lines.

[0006] Therefore, a technical solution is needed that can automatically check and locate contour lines according to set rules, accurately guide operators to perform repairs through prompt information, and reduce false alarms. Summary of the invention

[0007] The present application proposes a method and device for checking contour line contradictions, which solves the problems in the prior art that manual inspection of contour lines has a large workload and low efficiency, while automatic inspection will result in a large number of false alarms.

[0008] In a first aspect, an embodiment of the present application provides a method for checking contour line contradictions, comprising the steps of: Acquire a data set of a target area; the data set includes attribute data of contour lines; the attribute data includes elevation and contour interval; Several search lines diverge from the first contour line; Among the contour lines first encountered when the search line is extended, determine the second contour line whose number of intersections with the search line is greater than a set threshold; Determine the elevation difference between the first contour line and the second contour line according to the attribute data; Compare the elevation difference with the contour interval, and generate error data based on the comparison results.

[0009] In one of the embodiments, in response to the first search line extending to a line feature and / or a surface feature pattern that truncates the contour line, the divergence of the first search line is stopped.

[0010] In one embodiment, in response to the second search line extending to a map graphic area with different currentness, the divergence of the second search line is stopped.

[0011] Preferably, diverging the search lines from the first contour line along different angles includes at least one of the following methods: The search line is perpendicular to the first contour line; The search line diverges to both sides of the normal line of the first contour line at an acute angle with the first contour line; Starting from any node of the first contour line, multiple search lines are diverged along different angles; Change the search line density by increasing or decreasing the divergence angle.

[0012] Preferably, the plurality of search lines diverge outwards from a plurality of nodes of the first contour line, including at least one of the following methods; interpolating nodes on the first contour line at a set interval and / or a set number; Multiple search lines are diverged from each node; Change the search line density by increasing or decreasing the number of nodes in the diverging search line.

[0013] In one of the embodiments, a distance threshold is set, and in response to the extension length of the search line being greater than the distance threshold, the divergence is stopped.

[0014] In one of the embodiments, the search line density is changed by the divergence angle and / or the number of nodes; the variation pattern of the error amount with the search line density is statistically analyzed to determine the search line density within a set interval for the error amount increment or change rate.

[0015] In one of the embodiments, the search line density is changed by the divergence angle and / or the number of nodes; the variation pattern of the error amount with the search line density is statistically analyzed to determine the error information when the error amount change rate changes, and to shield the error information when the error rate change rate remains unchanged.

[0016] In a second aspect, the embodiment of the present application further provides a contour line contradiction checking device, which is used to implement the contour line contradiction checking method described in any one of the embodiments of the first aspect, and comprises: an acquisition module, which is used to acquire a data set of a target area. A determination module, which is used to diverge a search line from a first contour line; is also used to determine a second contour line; and is also used to determine the elevation difference between the two according to attribute data. A generation module, which is used to compare the elevation difference with the contour interval, and generate error data according to the comparison result.

[0017] In a third aspect, an embodiment of the present application further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method described in any one of the embodiments of the first aspect.

[0018] In a fourth aspect, an embodiment of the present application further provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the method described in any one of the embodiments of the first aspect when executing the computer program.

[0019] At least one of the above technical solutions adopted in the embodiments of the present application can achieve the following beneficial effects: This application can realize the inspection of the numerical contradiction of contour lines with multiple contour intervals in a piece of data. In order to overcome the problems of low efficiency and large workload of manual inspection, automatic scanning and identification are required. However, in order to overcome the false alarm of automatic inspection, that is, the problem of judging non-adjacent contour lines as adjacent contour lines or judging adjacent contour lines as non-adjacent contour lines, this application diverges several search lines from the target contour line, which can avoid missing reports, and can realize the density increase inspection of existing contour line nodes in the cache, that is, when the node spacing is too large, the contour line nodes are not enough, which may affect the inspection effect, and the graphics can be optimized by first increasing the nodes according to the specified spacing; it can also realize the inspection method focusing on strictness or efficiency (it can also ignore some error messages by adjusting parameters), focusing on strictness means generating search lines densely from more nodes, and the efficiency method is to automatically select some nodes at a specified number to reduce the search line density for inspection; it can realize the inspection of contour lines in special cases, the inspection of contour lines with different current potentials at the edge of the ground object coverage and data. Since a large number of false alarms will occur during high-density inspections, in some embodiments of the present application, the parameter setting of "ignore situations" can be achieved by adjusting parameters, introducing the error change rate, and optimizing the error amount. In practice, it can be achieved that when more than 99% of the situations are false alarms, the inspection setting can be ignored, thereby improving work efficiency and quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings: Figure 1.1 A schematic diagram showing a break or termination in a contour line; Figure 1.2 This is a schematic diagram of the discontinuity of contour lines caused by interference from ground objects; Figure 1.3 This is a schematic diagram of the discontinuity of contour lines due to map update boundaries; Figure 2 A flow chart of a method for checking contour line contradictions provided in an embodiment of the present application; Figure 3 A schematic diagram of a contour search line node starting point provided in an embodiment of the present application; Figure 4 Schematic diagram of various divergent modes of contour lines provided in the embodiment of the present application; Figure 5 Schematic diagram of a scenario where a single-dimensional search causes a false positive; Figure 6 Schematic diagram of the scenario for multiple search lines to avoid false negatives; Figure 7 A method for checking contour line contradictions for adjusting divergent density provided in an embodiment of the present application; Figure 8 This is a schematic diagram of the increase in the number of errors reported; Fig. 9 A method for checking contour line contradictions for shielding growth error information provided in an embodiment of the present application; Fig.10 This is a schematic diagram of the error information shielding area; Fig.11 A structural diagram of a contour line contradiction checking device provided in an embodiment of the present application; Fig.12 Schematic diagram of the commercial server system for the application scenario of this application. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the present application clearer, the technical solution of the present application will be clearly and completely described below in combination with the specific embodiments of the present application and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.

[0022] In each development stage of the surveying and mapping industry, a variety of topographic map results have been formed. Regardless of whether they are existing surveying and mapping results or new surveying and mapping results, various problems will be found when the results are used due to factors such as operating methods, operating standards and operating quality. For example, contour lines may have different codes and layers; due to different edge connection methods, there are many broken contour lines, and even broken lines with a certain distance (interrupted by points, text, etc.); the uneven expression of the beginning and end of the contour lines; the intersection of the contour lines themselves and each other; the partial overlap of the contour lines; the small Sharp angles (such as turning lines, small turning point angles, etc.); unreasonable contour lines (short contour lines); inconsistent elevation values ​​of multiple nodes of the contour line itself; the difference between the elevation values ​​of adjacent contour lines and the value of the contour interval are not equal; due to the current status of data updating in multiple regions, there are disturbances in the contour lines on both sides of the boundaries of regions with different current status; the present invention fully considers the data source, and performs customized parameter setting, inspection and repair based on the existing data source, which can effectively cope with the inspection of diverse data results, and at the same time can improve the inspection accuracy, effectively reduce false alarms and avoid missed alarms, so that operators can locate and modify more accurately.

[0023] The technical solutions provided by various embodiments of the present application are described in detail below in conjunction with the accompanying drawings.

[0024] Figure 1.1~1.3Some data environments of this application are shown by examples. In actual topographic map data, in order to achieve the finishing effect of the map, not all contour lines are closed. Only those in small areas that meet the closure conditions are closed, such as the complete mountain top in this area. However, since the contour lines of actual maps are often not theoretically closed curves, but often terminate or interrupt, the above changes in the contour line shape do not necessarily mean that there are errors in the map.

[0025] For example Figure 1.1 This is a schematic diagram of the interruption or termination of the contour line. There is a surface attachment at A. In order to avoid the surface attachment and not cause the graphics to overlap, the contour lines will be disconnected, that is, multiple lines will be blank. For example, at B, due to interference from other landforms such as steep slopes, the contour line is terminated. Here, the end point of the contour line in the surveying and mapping will produce random differences. The above situation will cause misjudgment of adjacent relationships. For example, at A, the contour lines 1 and 2 that are not adjacent are judged as adjacent relationships, and the same is true at B.

[0026] For another example, Figure 1.2 This is a schematic diagram of the discontinuity of contour lines caused by interference from ground objects. In area C, the plane distance between contour line 3 and the adjacent contour line 4 on the map is much larger than the plane distance between other contour lines. The computer can easily identify other contour line 5 as the adjacent contour line of contour line 3 in area C, or, due to special terrain relations, the adjacent contour line 4 cannot be searched.

[0027] For another example, different regions in the map data have different current characteristics, such as Figure 1.3 The contour lines shown in the figure are discontinuous due to the map update boundary. The part on the right side of the map sheet operation boundary 6 is updated. Therefore, the contour lines on the left and right sides are discontinuous and randomly uneven due to the disturbance of surveying and mapping errors. The above situation increases the difficulty of automatic recognition, resulting in false positives caused by incorrect recognition of adjacent relationships.

[0028] Figure 2 This is a flow chart of a method for checking contour line contradictions according to an embodiment of the present application, which realizes capturing contour line adjacent relationships and verifying values, and includes steps 110 to 150.

[0029] Step 110: Obtain a data set of the target area, wherein the data set includes attribute data of contour lines; the attribute data includes elevation and contour intervals of adjacent contour lines.

[0030] Furthermore, the attribute data of the contour lines also include one or more attribute values ​​such as elevation limit, distance limit, angle limit, characteristic feature code, contour line code, contour line layer value, etc.

[0031] In one embodiment, the data set further includes attribute data of characteristic features. Characteristic features are features that cut off contour lines. The concept of characteristic features is introduced. Characteristic features can be line features or surface features, can play a role in range limitation, or can be used for boundary isolation, and its parameters such as characteristic feature encoding, primitive representation, layer value, etc. can all be customized to meet the required parameter values. In the embodiment of the present application, characteristic features can be manually set through the GUI.

[0032] like Figure 1.1~1.3 As shown, the horizontally extending contour lines in the figure, including the first curve and the counting curve, are called contour lines. The difference in elevation values ​​between two adjacent contour lines (generally a positive number) is the contour interval. For example, taking 1:500 as an example, the contour interval is generally 0.5 meters. To check the contradiction between contour lines, it is generally to check whether this difference (which can be understood as an absolute value, or a large value minus a small value) is the contour interval, that is, 0.5; the lines extending up and down in the figure are characteristic features 14. The characteristic features in this figure are steep slopes, which may actually contain other features, such as ditches, roads, etc.

[0033] Step 120: Derive a number of search lines from the first contour line.

[0034] Diverge search lines from the first contour line to at least one side. The diverge search lines refer to setting a number of rays in any direction that is not parallel to the first contour line with a node on the first contour line as the origin.

[0035] The search lines are diverged by numerical calculation techniques and can be displayed in a graphical user interface.

[0036] In one embodiment, the plurality of search lines diverge outwards from a plurality of nodes of the first contour line. Figure 3 As shown, multiple search lines are diverged from each node 15 as a starting point.

[0037] Determine the node to include any of the following solutions: Interpolate nodes of the first contour line at a set interval. For example, strict calculation: supports setting whether to search for contour lines at equally spaced interpolation points. In one embodiment, the contour lines are interpolated at 1-meter intervals. If the parameter is 0, the original node processing is maintained. If it is set to 1, the line segments with original node spacing greater than 1 meter are encrypted at 1-meter intervals. Encryption is to optimize the algorithm. In further optimized embodiments, the interpolated nodes do not change the contour line data, but generate these interpolated nodes in the cache for calculation, and are not stored in the map database. Here, two options, strict calculation and efficient calculation, are also supported. Strict calculation means adding interpolated nodes and each interpolated node participates in the calculation; efficient calculation means using only a part of the nodes (including interpolated nodes and / or original nodes) to participate in the calculation.

[0038] In order to further improve the efficiency, the first contour line is set with equal parts nodes according to a set number. If the number of nodes in the first contour line is too large and it is inconvenient to calculate, it is necessary to reduce the number of nodes involved in the calculation. For example, in the efficiency calculation, in response to the number of nodes in the first contour line being greater than the set node number threshold, the first contour line is divided into equal parts according to the set node number, and each point that divides the first contour line equally participates in the calculation as an equal part node. The equal part node refers to dividing the first contour line into X segments after determining the number of segments X of the first contour line, and the position of each segment is taken as a new node. In a further optimized embodiment, the equal part node does not change the contour line data, but generates these equal part nodes in the cache for calculation, and does not store them in the map database.

[0039] It should be noted that, in the embodiments of the present application, one contour line may have two adjacent contour lines, for example, Figure 1.1~1.3 As shown, some contour lines have only one adjacent contour line, while most contour lines 1, 2, and 5 have adjacent contour lines on both sides. Some contour lines 3 and 4 have a flat terrain in area C due to the interference of characteristic objects 14, so their adjacent contour lines are far apart. In one embodiment, after determining the node, each node at least radiates a search line to both sides of the first contour line. It is possible to search for only one side of the contour line as an adjacent contour line, or to search for adjacent contour lines on both sides.

[0040] like Figure 4 As shown, contour line 1 diverges to both sides perpendicular to the search line where the contour line node is located, and multiple contour lines 2, 5, 9, and 13 are found.

[0041] It should also be noted that the contour lines of an actual map are curved, so the search lines generated from various nodes on the contour line at several divergent angles are generally not parallel, thus constituting a multi-dimensional search.

[0042] In step 120, how to set the plurality of search lines to form a multi-dimensional search further includes the following optional embodiment steps 120A-C: Step 120A, the first contour line generates a search line according to the set divergence angle; Step 120B, the first contour line generates a search line according to the set divergent nodes; Step 120C: Generate a search line according to the set divergence distance.

[0043] Steps 120A-C will be further described below in conjunction with subsequent steps.

[0044] In the embodiment of the present application, in order to further reduce false positives, an optional step 130 is further included between step 120 and step 140: Step 130: If the search line conflicts with other objects, the search line is terminated.

[0045] In one embodiment, in response to the first search line extending to a line feature and / or a surface feature pattern that truncates the contour line, the divergence of the first search line is stopped.

[0046] In one embodiment, in response to the second search line extending to a map graphic region with different currentness, the divergence of the second search line is stopped.

[0047] The timeliness of a database refers to the real-time or up-to-dateness of the data stored in the database. In other words, the timeliness of a database reflects the degree to which the data in the database is updated and changed. If the data in the database can promptly reflect the updates of the data by the external system or application, then the timeliness of the database is high. Therefore, this application also refers to different update times as different timeliness.

[0048] The benefit of step 130 is that it can avoid misidentification of adjacent contour lines due to discontinuous areas in the contour lines, thereby reducing false alarms. Figure 1.1 There is a building in area A, and stopping the search line from diverging will prevent the search line from crossing the blank area and mistakenly capturing adjacent contour lines. Under special terrain conditions, such as Figure 1.2 In the steep slope area shown, avoid judging the ending contour line 5 as the adjacent contour line of contour line 3 in area C. In the mapping areas with different current characteristics, for example Figure 1.3 On both sides of the map boundary shown, avoid judging the contour line 7 on one side as the adjacent contour line of the contour line 8 on the other side.

[0049] Step 140: Determine, among the contour lines first encountered when the search line is extended, a second contour line whose number of intersections with the search line is greater than a set threshold.

[0050] The search line extension refers to starting from the nodes of the first contour line (including the original nodes, interpolated nodes, and equally divided nodes on the contour line), searching along the search line in any direction not parallel to the first contour line, until another contour line is encountered for the first time as an alternative adjacent contour line.

[0051] It can be understood that due to the blank or uneven distribution formed by the interruption or termination of contour lines in the contour map, when the search is located in area A, B or C, another contour line encountered for the first time is not necessarily an adjacent contour line of the first contour line.

[0052] The plurality of search lines are traversed, and one or more contour lines are first encountered. A second contour line having a number of first-encountered intersection points greater than a set threshold generated by the plurality of search lines diverging from the first contour line is determined as an adjacent contour line.

[0053] It should be noted here that there may be multiple second contour lines whose number of intersections with the search line is greater than a set threshold.

[0054] Alternatively, all candidate adjacent contour lines that generate first-encounter intersections with the search lines diverging from the first contour line are compared, and the second contour line that generates the most intersections is selected as the true adjacent contour line.

[0055] Step 150: determine the elevation difference between the first contour line and the second contour line according to the attribute data, compare the elevation difference with the contour interval, and generate error reporting data according to the comparison result.

[0056] The attribute data contains the elevations of the first contour line and the second contour line. If the elevation difference is different from the contour interval, there is a contradiction between the two contour lines. Otherwise, there is no contradiction between the two contour lines. When the adjacent relationship between the second contour line and the first contour line is correct, according to the map surveying and mapping rules, the elevation difference between the two should be the same as the contour interval. Therefore, when the difference between the elevation difference and the contour interval of any captured second contour line exceeds the numerical representation error allowed by the map surveying and mapping rules, it means that the elevation difference between the two is different from the contour interval, there is a contradiction, and an error is generated.

[0057] If there are multiple contour intervals, when the height difference of the search lines on both sides of a contour line is inconsistent, it can also be judged and checked. The survey area is divided into two contour interval standards, which are generally clearly divided and will not be mixed together. Therefore, if there are two contour intervals on both sides of a contour line, it should be considered an error.

[0058] In step 150, error data is generated, in which the error number can be 0, that is, no contour error is found; when the second contour captured by any search line has an error, the error number will be accumulated according to the number of intersecting search lines.

[0059] Through the combination of the steps of the present application, the second contour line is captured through multiple search lines to avoid missing or misreporting. Figure 5 In the figure, the adjacent contour lines 11 and 12 identified by the one-dimensional single search line L (indicated by the dotted line) in the contour discontinuity area are not truly adjacent. Therefore, if the elevation difference and contour interval between the two are compared, errors will be reported due to different data, resulting in misreporting. Under conditions with rich landforms and geographical elements, there are many contour discontinuity areas, and similar misreporting situations will occur in large numbers.

[0060] According to the scheme of this application, a multidimensional search is implemented, for example Figure 6, multiple search lines (indicated by dotted lines) starting from the first contour line 1 node N intersect with multiple contour lines 5, 10, 11 according to the first encounter principle, and determine the second contour lines 5, 11 whose number of intersections is greater than the set threshold (to simplify the technical principle, assume that the threshold is 2, and the number of intersections between contour lines 5, 10, 11 and the search line is 3, 1, and 4 respectively). Practice has proved that under multi-dimensional search conditions, the number of intersections between contour lines and search lines that are mistakenly captured through the contour line discontinuity area is significantly smaller than that of adjacent contour lines. This avoids misreporting to a large extent.

[0061] Since the search density of multi-dimensional search is much greater than that of single-dimensional search, it can also reduce false negatives. Figure 6 The example also shows that multiple adjacent second contour lines 5 and 11 are obtained. Furthermore, if one of the second contour lines 5 has an elevation error (the elevation of the first contour line 1 is 2.5, the elevations of the second contour lines 5 and 11 are 3.5 and 3 respectively, and the contour interval is 0.5), the contour error is identified by comparing the elevation difference and the contour interval, and error data is generated. When the number of errors is accumulated according to the number of search lines that intersect with the identified erroneous contour line, Figure 6 In the example, the number of errors increased is 3, which is the number of intersecting search lines.

[0062] In combination with steps 120 to 150, an embodiment of how to set the plurality of search lines in step 120 is further described below: Step 120A: The first contour line generates a search line according to the set divergence angle.

[0063] In one embodiment, the first contour line diverges the search line along different angles, including at least one of the following modes: the search line is perpendicular to the first contour line, and the search line forms an acute angle with the first contour line. It can be understood that since contour lines are generally curves, even if the search lines are generated according to a set fixed divergence angle, these search lines are not parallel. In other words, the parallel search lines are only local or accidental.

[0064] The search line is perpendicular to the first contour line and can diverge outward at a faster speed. If the contour lines are relatively complete, the search line that diverges outward perpendicular to the first contour line can search for adjacent contour lines faster.

[0065] The divergence angle can be changed, such as the search line diverging toward both sides of the normal line of the first contour line at an acute angle with the first contour line.

[0066] The benefit of changing the divergence angle is that if the contour lines have more random variations due to termination, interruption and other issues, there may be a situation where the search line that diverges outward perpendicular to the first contour line cannot search for the second contour line. At this time, you can try to diverge in the direction of an acute angle with the first contour line.

[0067] For example, Figure 1.2 Contour line 3 in area C has a much larger plane distance on the map from its adjacent contour line 4 than the plane distances between other contour lines. Therefore, if we search from contour line 3 to the outside perpendicular to contour line 3, we may not find any other contour lines, or we may find other contour lines 2 and 5 (see Figure 4 ), are not adjacent contour lines, so by changing the divergence angle and diverging the search line in more directions, the probability of searching for adjacent contour lines can be increased.

[0068] For example, if the search line on the first contour line diverges outward and the search line perpendicular to the first contour line at the origin fails to find the second contour line, the divergence angle value can be expanded from both sides of the vertical direction of the first contour line to search, such as 45 degrees, to see whether the second contour line can be found.

[0069] In one embodiment of the present application, multiple search lines are diverged from any node of the first contour line along different angles. The advantage of adding multiple divergence angles is that the probability of searching the second contour line is increased by changing the search line density and range by increasing or decreasing the divergence angle. If the expansion of the divergence angle fails to recapture the adjacent contour line, the angle can be further expanded until the adjacent contour line is captured or the set angle threshold is reached.

[0070] Step 120B: The first contour line generates a search line according to the set divergent nodes.

[0071] In one embodiment, the plurality of search lines diverge outward from a plurality of nodes of the first contour line, including at least one of the following methods: interpolating nodes or equally dividing nodes at a set interval and / or a set number on the first contour line; changing the search line density by increasing or decreasing the number of nodes of the diverging search lines, and the diverging nodes can be the original nodes of the contour line, or the interpolated nodes or equally divided nodes generated by the cache.

[0072] The advantage of increasing the number of nodes is that the nodes are arranged on the first contour line at a set interval, so the positions of multiple nodes are different. Each node diverges the search line outward in the manner of step 120A, which can improve the efficiency of finding the second contour line.

[0073] For example, Figure 1.1 For area A, if the node of contour line 1 is below area A, the search line diverging from contour line 1 is likely to directly search contour line 2, while contour line 2 is not an adjacent contour line of contour line 1. If multiple nodes are selected, since each node has a different position in the length direction of the first contour line, the nodes far away from area A will not search contour line 2 because of area A, reducing the possibility of misjudgment.

[0074] Step 120C: Generate a search line according to the set divergence distance.

[0075] In one of the embodiments, a distance threshold is set, and in response to the extension length of the search line being greater than the distance threshold, the divergence is stopped.

[0076] When checking for conflicts between contour lines, the search is generally not done indefinitely. Instead, a maximum distance limit is given, such as 100 meters. That is, only contour lines within 100 meters are allowed to be judged as conflicting.

[0077] Since the scale of the map is fixed, the distance between the second contour line adjacent to the first contour line is within a certain range. If the search line diverges outward without limit, it will burden the system computing resources. Beyond a certain distance, the searched line is unlikely to be an adjacent contour line. Therefore, setting the divergence distance can reduce the burden on the system.

[0078] like Figure 4 As shown, the first search line diverging from the right contour line 3 in the figure extends to the characteristic feature 14, or no contour line or characteristic feature is found (ie, the length extends beyond 100 meters), and the divergence of the first search line is stopped.

[0079] Note: To ensure complete identification, there are multiple combinations of parameter adjustment schemes based on the above situations. For example, first adjust the number of points, then adjust the divergence angle of each node; or other schemes. Until all contour lines are traversed, avoid leaving isolated contour lines.

[0080] The isolated contour line refers to a contour line that is not captured by any search line, and the search line diverging from the contour line also does not capture other contour lines.

[0081] For example, such contour lines should change parameters and diverge the search line again. For example, if the vertical divergence search line does not find an adjacent contour line, a secondary divergence search is performed through a search line that is at an acute angle to the first contour line. When an adjacent contour line is found, this isolated contour line is excluded.

[0082] like Figure 4 As shown, the adjacent contour lines 3 and 4 are uneven. If the search line diverges outwards and is perpendicular to the contour line where the node is located, the search line may not be able to find the adjacent contour line. However, the adjacent contour lines do exist. Therefore, through the traversal process, the divergence angle is first set to traverse different contour lines as the first contour line (for example, the search line diverging from a contour line 3 does not capture any adjacent contour lines, but the search line diverging from another contour line 4 captures the contour line 3). If there are still isolated contour lines, the divergence angle is traversed again, which can improve efficiency.

[0083] In one embodiment, two contour lines are respectively used as first contour lines to search for each other outwardly, and in response to one contour line searching for another, a contradiction check is performed. For example, when a certain contour line is used as the first contour line to search outwardly, another contour line that actually exists may not be captured based on the set search scheme, but if the other contour line is used as the first contour line to search outwardly and captures the certain contour line, it means that the two have captured an adjacent relationship and a contradiction check needs to be performed.

[0084] Furthermore, all isolated contour lines are searched out separately and manually judged whether they are reasonable. Parameter selection is supported here, 0 for no, 1 for yes. Selecting 1 means that this step needs to be performed. This is equivalent to an extremely special case or a single contour line can be judged to be a contour line of the same elevation, but there is no adjacent relationship. This situation is generally a special existence and can be handled manually.

[0085] Figure 7 The flowchart of the method for checking the contradiction of contour lines for adjusting the divergent density is as follows. The number of errors is based on the cumulative number of search lines that intersect with the identified erroneous contour lines. Further, the method of the embodiment of the present application also includes a method for checking the contradiction of contour lines for adjusting the divergent density. Although multidimensional search can avoid underreporting, search lines with too high a density will lead to a large number of false positives, that is, contour lines with non-adjacent relationships are captured as adjacent relationships, and then errors are reported when comparing elevation differences. To determine a reasonable density of search lines, the steps of the embodiment are as follows: Step 210 is the same as step 110.

[0086] Step 220, changing the search line density by setting the divergence angle and / or the number of nodes.

[0087] Steps 120 to 140 are repeatedly executed under different search line density conditions to generate error reporting data under different search line density conditions.

[0088] Step 230: Count the variation of the error amount with the search line density, and determine the search line density within the set interval of the error amount variation rate.

[0089] It can be understood that when the search line density is small, there are more missed reports; when the search line density is large, the missed reports are reduced, but as the number of false reports increases, for example, the number of search lines crossing the contour discontinuity area increases, the number of false reports will further increase, most of which are false reports. Figure 8The figure shows the growth of error amount. In interval R1, the error amount is at an unreasonable low value, in interval R2, the error amount increases reasonably, and in interval R3, the error amount increases unreasonably. The error amount change rate r is defined as the ratio of the error amount growth value 𝛥e to the search line number growth value 𝛥c, that is, the slope of the curve. Practice shows that when the number of search lines crossing the contour discontinuity area increases, r will also increase. Therefore, R2 is set to a reasonable error amount change interval, such as the error amount interval R2=[e1,e2], or R2 is set to a reasonable error amount change rate interval R2=[r1,r2].

[0090] Fig. 9 A method for checking contour contradictions for shielding increasing error messages. Under the condition that the number of errors is accumulated according to the number of search lines that intersect with the identified erroneous contour lines, further, the embodiment of the present application also proposes a method for checking contour contradictions for optimizing the error amount. Although setting the search line density can avoid a large number of false alarms, within the set search line density range, as the search line density increases, a large number of repeated errors will be generated. The present application shields error messages under set conditions, which can effectively reduce the number of repeated errors. The following steps are included: Step 310 is the same as step 110.

[0091] Step 320: Change the search line density by setting the divergence angle and / or the number of nodes.

[0092] Steps 120 to 140 are repeatedly executed under different search line density conditions to generate error reporting data under different search line density conditions.

[0093] Step 330: Count the changing rules of the error amount with the search line density, determine the error information when the error amount change rate changes, and shield the error information when the error rate change rate remains unchanged.

[0094] For example, when affected by an identified contour error event, as the number of search lines increases, the number of errors will increase at a fixed rate, such as r1. When a new identified contour error event occurs, the rate of increase in the number of errors will increase, such as r2, because more error events contribute to the number of errors. Therefore, when the rate of change of the number of errors changes, new contour error events can be identified. When the rate of change of the number of errors remains unchanged, the number of new errors is the result of the same event, that is, repeated errors will be generated. Fig.10 This is a schematic diagram of the error information shielding area, where r2>r1>r0. In response to a change in the error amount change rate, a reporting gap is set to generate new error information. Furthermore, when the error amount increases with the increase in the number of search lines but the error amount change rate remains unchanged, a shielding area is set to avoid further error information being generated.

[0095] Those skilled in the art can understand that combinations of the above embodiments are also reasonable.

[0096] It should also be noted that regarding setting the parameters of the search line density, such as the number of nodes, node spacing, divergence angle, etc., as well as meeting the requirements for the number of error messages and reducing false positives and missed reports, artificial intelligence learning methods can be introduced to train the above parameters, and parameter values ​​that meet the needs can be set according to the area of ​​interest.

[0097] Fig.11 This is a structural diagram of a high-line contradiction checking device according to an embodiment of the present application, which is used to implement the high-line contradiction checking method according to any embodiment of the first aspect, including: The acquisition module 510 is used to acquire a data set of the target area. The acquisition module is also used to implement other functions described in step 110 of the embodiment of the present application, which will not be described in detail here.

[0098] Determining module 520, for radiating a search line from a first contour line; for determining a second contour line; and for determining an elevation difference between the first contour line and the second contour line according to the attributes of the first contour line and the second contour line; Determine the first contour line and radiate search lines from the first contour line to both sides; also used to determine the second contour line as an adjacent contour line; also used to determine the attribute data of the second contour line, and determine the elevation difference between the first contour line and the second contour line according to the data attributes of the first contour line and the second contour line.

[0099] The determination module is also used to implement other functions described in steps 120 to 150 of the embodiment of the present application, which will not be repeated here.

[0100] The generating module 530 is used to compare the elevation difference with the contour interval and generate error reporting data according to the comparison result.

[0101] To further implement the functions of steps 120 to 150, the determination module includes a first determination unit, which is used to diverge the search line from the first contour line; is also used to determine the second contour line; and is also used to determine the elevation difference between the first contour line and the second contour line according to their attributes.

[0102] In some embodiments, the first determination unit is further configured to change the search line density by setting a divergence angle and / or a number of nodes. In one embodiment, the determination module further includes a second determination unit configured to diverge the search line along different angles of the first contour line, including at least one of the following methods: The search line is perpendicular to the first contour line; The search line diverges to both sides of the normal line of the first contour line at an acute angle with the first contour line; Starting from any node of the first contour line, multiple search lines are diverged along different angles; Change the search line density by increasing or decreasing the divergence angle.

[0103] The above embodiment is specifically used to implement any technical feature in step 120A.

[0104] In one of the embodiments, the determination module further comprises a third determination unit, which is used to determine the line feature and / or surface feature graphics that truncate the contour line.

[0105] The determination module further comprises a fourth determination unit for determining a map graphic area extending to different currentness.

[0106] The above-mentioned embodiment is specifically used to implement any technical feature in step 130 .

[0107] In one embodiment, the determination module further comprises a fourth determination unit, which is used to determine the interpolation nodes on the first contour line according to a set interval and / or a set number.

[0108] It is also used to radiate multiple search lines starting from each node.

[0109] Also used to change the search line density by increasing or decreasing the number of nodes.

[0110] The above embodiment is specifically used to implement any technical feature in step 120B.

[0111] In one of the embodiments, a fifth determining unit is further included, configured to stop diverging in response to the extension length of the search line being greater than a distance threshold.

[0112] The above embodiment is specifically used to implement any technical feature in step 120C.

[0113] In one embodiment, the determination module further includes a sixth determination unit, which is used to calculate the variation rule of the error amount with the search line density and determine the search line density within a set interval of the error amount variation rate.

[0114] The above embodiment is specifically used to implement any technical feature in steps 210 to 230.

[0115] In one embodiment, the determination module further includes a seventh determination unit for counting the variation of the error amount with the search line density, determining the error information when the error amount variation rate changes, and shielding the error information when the error rate variation rate remains unchanged.

[0116] The above embodiment is specifically used to implement any technical feature in steps 310 to 330.

[0117] In one of the embodiments, it also includes a contour information database / result map database 540, and the geographic information database / result map database is used to store the ground feature data before and after the contour line conflict check.

[0118] Fig.12 Schematic diagram of the commercial server system for the application scenario of this application.

[0119] An embodiment of the present application also proposes a graphics processing system for geographic information data, which is used to implement the method described in any embodiment of the present application, including: a map database 610, a data processor 620, a GUI operation interface 630, an application terminal 640, and at least one result map data set 650.

[0120] The map database is used to store the data set of the target area.

[0121] The GUI operation interface and / or application terminal is used to input setting conditions. The acquisition module, determination module or generation module is triggered. The data processor, in response to the instruction of the GUI, acquires the attribute data of the contour line of the target area, and determines whether there is a contradiction between the adjacent contour line and the contour line through the attribute data of the contour line; the result map data set is used to store the relevant data of the contour line of the target area.

[0122] It should be understood that the above-mentioned specific related contents are only used for illustrative purposes and should not impose any limitation on the present application.

[0123] The specific method for implementing the functions of the above-mentioned modules is as described in the various method embodiments of the first aspect of the present application, and will not be repeated here.

[0124] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0125] Therefore, the present application also proposes a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, the method described in any embodiment of the present application is implemented.

[0126] The present invention is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present invention. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate a device for implementing the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0127] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory produce a manufactured product including an instruction device that implements the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0128] These computer program instructions may also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, whereby the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0129] Furthermore, the present application also proposes an electronic device (or computing device), comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the method described in any embodiment of the present application when executing the computer program.

[0130] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory. Memory may include non-permanent storage in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. Memory is an example of a computer-readable medium. Computer-readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. The information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices or any other non-transmission medium that can be used to store information that can be accessed by a computing device. According to the definition in this article, computer-readable media does not include temporary computer-readable media (transitory media), such as modulated data signals and carrier waves.

[0131] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0132] In the description of the present application, it should be understood that the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances. In addition, in the description of the present application, unless otherwise specified, "multiple" refers to two or more. "Several" refers to one or more. In some embodiments, if it is obviously inappropriate to understand "several" as one, it means multiple.

[0133] In this application, "and / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0134] The above is only an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A method for checking contour line contradictions, characterized in that: Contains steps: Acquire a data set of a target area; the data set includes attribute data of contour lines; the attribute data includes elevation and contour interval; Several search lines diverge from the first contour line; Among the contour lines first encountered when the search line is extended, determine the second contour line whose number of intersections with the search line is greater than a set threshold; Determine the elevation difference between the first contour line and the second contour line according to the attribute data; Compare the elevation difference with the contour interval, and generate error data based on the comparison results.

2. The method for checking contour line contradictions according to claim 1, characterized in that: Diverge search lines from the first contour line at different angles, including at least one of the following methods: The search line is perpendicular to the first contour line; The search line diverges to both sides of the normal line of the first contour line at an acute angle with the first contour line; Starting from any node of the first contour line, multiple search lines are diverged along different angles; Change the search line density by increasing or decreasing the divergence angle.

3. The method for checking contour line contradictions according to claim 1, characterized in that: In response to the first search line extending to the line feature and / or the surface feature pattern that cuts off the contour line, stopping the divergence of the first search line; and / or In response to the second search line extending to a map graphic region with different currentness, the divergence of the second search line is stopped.

4. The method for checking contour line contradictions according to claim 1, characterized in that: The plurality of search lines diverge outward from the plurality of nodes of the first contour line, including at least one of the following methods; interpolating nodes on the first contour line at a set interval and / or a set number; Multiple search lines are diverged from each node; Change the search line density by increasing or decreasing the number of nodes in the diverging search line.

5. The method for checking contour line contradictions according to claim 1, characterized in that: A distance threshold is set, and in response to the extension length of the search line being greater than the distance threshold, the divergence is stopped.

6. The method for checking contour contradictions according to claim 1, characterized in that: Changing the search line density by divergence angle and / or number of nodes; The variation law of error amount with search line density is statistically analyzed to determine the search line density of error amount increment or change rate within the set interval.

7. The method for checking contour contradictions according to claim 1, characterized in that: Changing the search line density by divergence angle and / or number of nodes; Statistically calculate the changing pattern of the error amount with the search line density, determine the error information when the error amount change rate changes, and shield the error information when the error rate change rate remains unchanged.

8. A contour line contradiction detection device, characterized in that: The method for checking contour line contradictions according to any one of claims 1 to 7 comprises: An acquisition module is used to acquire a data set of a target area; A determination module is used to diverge a search line from a first contour line; is also used to determine a second contour line; and is also used to determine the elevation difference between the two according to attribute data; The generation module is used to compare the elevation difference and the contour interval, and generate error data based on the comparison results.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

10. An electronic device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the method according to any one of claims 1 to 7 is implemented.

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