Method and device for determining channel area, medium and program product

Abstract

The invention provides a method and a device for determining a navigation channel area, a medium and a program product. The method comprises the following steps: S1, acquiring position coordinates of navigation mark points contained in each water channel; s2, for each water channel, determining a radius parameter alpha of a corresponding alpha polygon according to the position coordinates of a group of navigation mark points corresponding to the water channel; s3, for each water channel, obtaining an alpha polygon corresponding to the navigation mark point of the water channel; s4, obtaining a nearest point pair of the navigation mark points between every two alpha polygons, and determining the alpha polygons of which the distance between the nearest point pairs is smaller than a preset distance; s5, for any two alpha polygons of which the distance between the nearest point pairs is smaller than a preset distance, determining a second polygon connected with the alpha polygons; and S6, combining all the alpha polygons and the second polygons to obtain a channel region. By means of the technical scheme, the navigation mark point information is used, and the navigation channel area can be determined in time when the navigation channel area changes.

Description

Technical Field

[0001] The present invention relates to the field of navigation supervision, and in particular to a method, device, medium and program product for determining a waterway area. Background Art

[0002] Ship navigation status supervision is crucial for safe navigation of ships. Real-time channel areas are often required during supervision. However, traditional channel charts are slow to update, inefficient, and costly to update, and it is impossible to obtain updated channel areas in time when the channel areas change. Summary of the invention

[0003] The embodiments of the present invention provide a method, device, medium and program product for determining a channel area, so as to timely determine the channel area when the channel area changes.

[0004] In order to achieve the above object, on the one hand, a method for determining a waterway area is provided, comprising:

[0005] S1, obtaining the position coordinates of the navigation points contained in each waterway, wherein each waterway corresponds to a group of navigation points;

[0006] S2, for each waterway, according to the position coordinates of a group of navigation points corresponding to the waterway, determine the radius parameter α of the alpha polygon corresponding to the group of navigation points:

[0007] α=w*ln(longitude variance +latitude variance +1)

[0008] The location coordinates include the longitude and latitude of the navigation point. variance is the longitude variance of the set of navigation points, latitude variance is the latitude variance of the group of navigation points, w is a predetermined parameter, w is less than 25000 and greater than 15000;

[0009] S3, for each waterway, obtain the alpha polygon corresponding to the navigation point of the waterway, including:

[0010] According to a set of navigation points corresponding to the waterway, the Delaunay triangulation T corresponding to the set of navigation points is constructed. i , i = 1…N, N is the total number of waterways;

[0011] For the T i For each triangle in the , calculate the radius R of the circumscribed circle of the triangle, and set the R that does not satisfy Remove the triangles to obtain the set of available triangles corresponding to the waterway;

[0012] Extract the edge belonging to only one triangle among all the triangles included in the available triangle set as a boundary, and use the extracted boundary to construct a closed polygon, the constructed closed polygon is the alpha polygon corresponding to the waterway;

[0013] S4, traversing all the obtained alpha polygons, obtaining the closest point pair of navigation points between every two alpha polygons, and determining the alpha polygons whose distance between the closest point pairs is less than a predetermined distance;

[0014] S5, for any two alpha polygons among the alpha polygons whose distance between the closest point pairs is less than a predetermined distance, determine a second polygon connecting the alpha polygons:

[0015] Determine the edge where the closest point pair of these two alpha polygons lies;

[0016] Get the endpoints of the edge where the closest point pair is located;

[0017] Connect the obtained endpoints in sequence to obtain a first polygon related to the two polygons;

[0018] When the overlapping area between the first polygon and any one of the two alpha polygons is smaller than a predetermined area threshold, the first polygon is determined as the second polygon to be retained;

[0019] S6, merging the alpha polygons corresponding to all waterways and the determined second polygons, and the obtained merged area is the determined waterway area.

[0020] Preferably, in the method, in step S2, the radius parameter α is constrained within the range of [30, 50].

[0021] In step S3, for T i Any triangle Δ in ijk , calculate the circumscribed circle radius R by the following formula:

[0022]

[0023] Among them, p i , p j and p k For triangle Δ ijk The three vertices of Area(Δ ijk ) is a triangle Δ ijk The area of ​​​​the i -p j ‖ is p i and p j The Euclidean distance between j -pk ‖ is p j and p k The Euclidean distance between k -p i ‖ is p k and p i The Euclidean distance between .

[0024] Preferably, the method further comprises one or more of the following:

[0025] w = 20000;

[0026] The predetermined distance is less than 3 km;

[0027] The area threshold is represented by longitude and latitude, and the area threshold is less than or equal to 0.000009.

[0028] Preferably, in the method, the predetermined distance is 2.5 km; and the area threshold is 0.000006.

[0029] Preferably, in the method, in step S4, the Euclidean distance is used to measure the distance between any two navigation points between two alpha polygons.

[0030] Preferably, in the method, in step S1, the position coordinates of the navigation points included in each waterway are obtained at regular intervals.

[0031] On the other hand, a device for determining a waterway area is provided, comprising a memory and a processor, wherein the memory stores at least one program, and the at least one program is executed by the processor to implement the steps of any of the methods described above.

[0032] On the other hand, a computer-readable storage medium is provided, wherein at least one program is stored in the storage medium, and the at least one program is executed by a processor to implement the steps of any of the methods described above.

[0033] On the other hand, a computer program product is provided, comprising a computer program, characterized in that when the computer program is executed by a processor, the steps of any of the methods described above are implemented.

[0034] The above technical solution has the following technical effects:

[0035] The technical solution of the embodiment of the present invention obtains the location information of the navigation points in the waterway, uses the location information of each waterway navigation point to determine the alpha polygon corresponding to each waterway, and further uses the polygon determined by the nearest point pair of each alpha polygon to determine the second polygon used to merge the separated alpha polygons, and finally merges all the alpha polygons and the second polygon to determine the channel area; the technical solution of the embodiment of the present invention can obtain the latest channel area in time by using the current latest location information of the navigation point;

[0036] Furthermore, by periodically acquiring the position coordinates of navigation points contained in each waterway, dynamic determination of the waterway area can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 A schematic diagram of a flow chart of a method for determining a waterway area according to an embodiment of the present invention;

[0038] Figure 2 is an exemplary waterway information;

[0039] Figure 3 A schematic diagram of the structure of a computer system according to an embodiment of the present invention;

[0040] Figure 4 Based on Figure 2 A schematic diagram of the navigation area with the final determination of the waterway and navigation points shown;

[0041] Figure 5 It is a schematic diagram of the structure of a device for determining a waterway area according to an embodiment of the present invention. DETAILED DESCRIPTION

[0042] To further illustrate the various embodiments, the present invention provides drawings. These drawings are part of the disclosure of the present invention, which are mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these contents, a person of ordinary skill in the art should be able to understand other possible implementations and advantages of the present invention. The components in the figures are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0043] The present invention will now be further described with reference to the accompanying drawings and specific implementation methods.

[0044] Embodiment 1:

[0045] Figure 1 FIG. 1 is a flow chart of a method for determining a waterway area according to an embodiment of the present invention. Figure 1 The method for determining the waterway area of ​​this embodiment includes the following steps:

[0046] S1, obtaining the position coordinates of the navigation points included in each waterway, wherein each waterway corresponds to a group of navigation points; preferably, obtaining the position coordinates of the navigation points included in each waterway at regular intervals;

[0047] In a specific implementation, the navigation points contained in the waterway are determined according to the waterway ID in the navigation information;

[0048] Figure 2 This is an exemplary waterway information. Different colors represent different waterways. The circle in the waterway represents the navigation point contained in the waterway.

[0049] S2, for each waterway, according to the position coordinates of a group of navigation points corresponding to the waterway, determine the radius parameter α of the alpha polygon corresponding to the group of navigation points:

[0050] α=w*ln(longitude variance +latitude variance +1)

[0051] The location coordinates include the longitude and latitude of the navigation point. variance is the longitude variance of the set of navigation points, latitude variance is the latitude variance of the group of navigation points, w is a predetermined parameter, w is less than 25000 and greater than 15000; preferably, w=20000;

[0052] Preferably, the radius parameter α is constrained within the range of [30,50];

[0053] In the specific implementation, the alpha polygon algorithm (alpha shape algorithm) is a prior art, and the radius parameter α used in the alpha shape algorithm is a prior art, which will not be described in detail here;

[0054] S3, for each waterway, obtain the alpha polygon corresponding to the navigation point of the waterway, including:

[0055] According to a set of navigation points corresponding to the waterway, the Delaunay triangulation T corresponding to the set of navigation points is constructed. i , i = 1…N, N is the total number of waterways;

[0056] For t i For each triangle in the , calculate the radius R of the circumscribed circle of the triangle, and set R that does not satisfy Remove the triangles to obtain the set of available triangles corresponding to the waterway;

[0057] Extract the edge belonging to only one triangle among all the triangles included in the available triangle set as a boundary, and use the extracted boundary to construct a closed polygon, the constructed closed polygon is the alpha polygon corresponding to the waterway;

[0058] Among them, Delaunay triangulation is an optimal triangulation of a point set, which satisfies the following properties:

[0059] The circumcircle of each triangle contains no other points;

[0060] The minimum angle of the triangle is maximized to avoid "skinny" triangles;

[0061] In step S3, for T i Any triangle Δ in ijk , calculate the circumscribed circle radius R by the following formula:

[0062]

[0063] Among them, p i , p j and p k For triangle Δ ijk The three vertices of Area(Δ ijk ) is a triangle Δ ijk The area of ​​​​the i -p j ‖ is p i and p j The Euclidean distance between j -p k ‖ is p j and p k The Euclidean distance between k -p i ‖ is p k and p i The Euclidean distance between

[0064] Figure 3 For Figure 2 Schematic diagram of the alpha polygons obtained for the waterways and navigation points shown;

[0065] S4, traversing all the obtained alpha polygons, obtaining the closest point pair of navigation points between every two alpha polygons, and determining the alpha polygons whose distance between the closest point pairs is less than a predetermined distance; preferably, the predetermined distance is less than 3 km; preferably, the predetermined distance is 2.5 km;

[0066] In a specific implementation, the Euclidean distance is used to measure the distance between any two navigation points between two alpha polygons;

[0067] Specifically, the distance d(a, b) between any two points a and b between two alpha polygons, where the two polygons A and B are represented by the sets of navigation points they contain;

[0068]

[0069] Among them, a x and b x is the horizontal coordinate of point a and b, a y and b y is the ordinate of points a and b;

[0070] The closest point pair between two alpha polygons A and B, i.e. the closest point pair of navigation points (p, q), refers to p∈A and q∈B that satisfy the following conditions:

[0071]

[0072] Here A×B represents the set of all possible point pairs;

[0073] S5, for any two alpha polygons among the alpha polygons whose distance between the closest point pairs is less than a predetermined distance, determining a second polygon connecting the alpha polygons, including:

[0074] Determine the edge where the closest point pair of these two alpha polygons lies;

[0075] Get the endpoints of the edge where the closest point pair is located;

[0076] Connect the obtained endpoints in sequence to obtain a first polygon related to the two polygons;

[0077] When the overlapping area between the first polygon and any one of the two alpha polygons is less than a predetermined area threshold, the first polygon is determined as the second polygon to be retained; preferably, the area threshold is expressed by longitude and latitude, and the area threshold is less than or equal to 0.000009; preferably, the area threshold is 0.000006;

[0078] S6, merging the alpha polygons corresponding to all waterways and the determined second polygons, and the obtained merged area is the determined waterway area.

[0079] Figure 4 Based on Figure 2 Schematic diagram of the waterway area with the final determination of the waterway and navigation points shown.

[0080] Embodiment 2:

[0081] The present invention also provides a device for determining a waterway area, such as Figure 5As shown, the device includes a processor 501, a memory 502, a bus 503, and a computer program stored in the memory 502 and executable on the processor 501. The processor 501 includes one or more processing cores. The memory 502 is connected to the processor 501 via the bus 503. The memory 502 is used to store program instructions. When the processor executes the computer program, the steps in the above method embodiment of the first embodiment of the present invention are implemented.

[0082] Further, as an executable solution, the device for determining the waterway area may be a computer unit, which may be a computing device such as a desktop computer, a notebook, a PDA, or a cloud server. The computer unit may include, but is not limited to, a processor and a memory. Those skilled in the art will appreciate that the composition structure of the above-mentioned computer unit is merely an example of a computer unit and does not constitute a limitation on the computer unit, and may include more or fewer components than the above-mentioned, or a combination of certain components, or different components. For example, the computer unit may also include input and output devices, network access devices, buses, etc., which are not limited in the embodiments of the present invention.

[0083] Further, as an executable solution, the processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc. The processor is the control center of the computer unit, and various interfaces and lines are used to connect the various parts of the entire computer unit.

[0084] The memory can be used to store the computer program and / or module, and the processor realizes various functions of the computer unit by running or executing the computer program and / or module stored in the memory, and calling the data stored in the memory. The memory can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system and at least one application required for a function; the data storage area can store data created according to the use of the mobile phone, etc. In addition, the memory can include a high-speed random access memory, and can also include a non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (SecureDigital, SD) card, a flash card (Flash Card), at least one disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0085] Embodiment three:

[0086] The present invention also provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the above method in the embodiment of the present invention are implemented.

[0087] If the module / unit integrated in the computer unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present invention implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned various method embodiments when executed by the processor. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory) and software distribution medium, etc. It should be noted that the content contained in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction.

[0088] Embodiment 4:

[0089] The present invention also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the steps of the method described above are implemented.

[0090] Although the present invention has been specifically shown and described in conjunction with the preferred embodiments, it should be understood by those skilled in the art that various changes may be made to the present invention in form and details without departing from the spirit and scope of the present invention as defined by the appended claims, all of which are within the scope of protection of the present invention.

Claims

1. A method for determining a waterway area, characterized in that: include: S1, obtaining the position coordinates of the navigation points contained in each waterway, wherein each waterway corresponds to a group of navigation points; S2, for each waterway, according to the position coordinates of a group of navigation points corresponding to the waterway, determine the radius parameter α of the alpha polygon corresponding to the group of navigation points: α=w*ln(longitude variance +latitude variance +1) The location coordinates include the longitude and latitude of the navigation point. variance is the longitude variance of the set of navigation points, latitude variance is the latitude variance of the group of navigation points, w is a predetermined parameter, w is less than 25000 and greater than 15000; S3, for each waterway, obtain the alpha polygon corresponding to the navigation point of the waterway, including: According to a set of navigation points corresponding to the waterway, the Delaunay triangulation T corresponding to the set of navigation points is constructed. i , i = 1…N, N is the total number of waterways; For the T i For each triangle in the , calculate the radius R of the circumscribed circle of the triangle, and set the R that does not satisfy Remove the triangles to obtain the set of available triangles corresponding to the waterway; Extract the edge belonging to only one triangle among all the triangles included in the available triangle set as a boundary, and use the extracted boundary to construct a closed polygon, the constructed closed polygon is the alpha polygon corresponding to the waterway; S4, traversing all the obtained alpha polygons, obtaining the closest point pair of navigation points between every two alpha polygons, and determining the alpha polygons whose distance between the closest point pairs is less than a predetermined distance; S5, for any two alpha polygons among the alpha polygons whose distance between the closest point pairs is less than a predetermined distance, determine a second polygon connecting the alpha polygons: Determine the edge where the closest point pair of these two alpha polygons lies; Get the endpoints of the edge where the closest point pair is located; Connect the obtained endpoints in sequence to obtain a first polygon related to the two polygons; When the overlapping area between the first polygon and any one of the two alpha polygons is smaller than a predetermined area threshold, the first polygon is determined as the second polygon to be retained; S6, merging the alpha polygons corresponding to all waterways and the determined second polygons, and the obtained merged area is the determined waterway area.

2. The method according to claim 1, characterized in that In the step S2, the radius parameter α is constrained to be within the range of [30, 50]. In step S3, for T i Any triangle Δ in ijk , calculate the circumscribed circle radius R by the following formula: Among them, p i , p j and p k For triangle Δ ijk The three vertices of Area(Δ ijk ) is a triangle Δ ijk The area of ​​​​the i -p j ‖ is p i and p j The Euclidean distance between j -p k ‖ is p j and p k The Euclidean distance between k -p i ‖ is p k and p i The Euclidean distance between .

3. The method according to claim 1, characterized in that: Also includes one or more of the following: w＝20000； The predetermined distance is less than 3 km; The area threshold is represented by longitude and latitude, and the area threshold is less than or equal to 0.000009.

4. The method according to claim 1, characterized in that The predetermined distance is 2.5 km; the area threshold is 0.000006.

5. The method according to claim 1, characterized in that In step S4, the Euclidean distance is used to measure the distance between any two navigation points between two alpha polygons.

6. The method according to claim 1, characterized in that In the step S1, the position coordinates of the navigation points included in each waterway are obtained at regular intervals.

7. A device for determining a waterway area, characterized in that: The method comprises a memory and a processor, wherein the memory stores at least one program, and the at least one program is executed by the processor to implement the steps of any one of the methods according to claims 1 to 6.

8. A computer-readable storage medium, characterized in that: The storage medium stores at least one program, and the at least one program is executed by a processor to implement the steps of any one of the methods described in claims 1 to 6.

9. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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