JP2008292248A - Route information generation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a route information generation device which further compresses, compared to the past, a quantity of information for specifying a route such as a traveling route, and reproduces the route accurately when decompressed. <P>SOLUTION: In S20, assuming a map code just after start of route information generation processing as P0, and each map code acquired successively thereafter as P1, P2, etc., P(n-1), Pn, ETC., respectively (equivalent to compression route information of this invention), each difference is taken such as P1-P0, P2-P1, etc., Pn-P(n-1), etc.. Assuming difference information determined by taking differences between map codes in the order of youth as ΔP1, ΔP2, etc., ΔPn, etc., pieces of differential information each of which is shown as ΔP1=P1-P0, ΔP2=P2-P1, etc., ΔPn=Pn-P(n-1), etc., respectively are generated. In S16, a processing for adding ΔP1, ΔP2, etc., ΔPn, etc., successively to the map code P0, and storing the result is executed. In this navigation device, since each unit or core has a size specifying the traveling route on a map, even if a route is specified by using a map code showing the position of each unit or core, the route can be shown accurately on the map. Since traveling route information using the difference information is determined by taking the difference between the map codes, an error is not generated, when being converted into traveling route information using the map codes, namely, when decompressed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a route information generation device that generates route information of a route shown on a map.

  Conventionally, as a method for specifying a travel route, a method is used in which a current position is measured using a GPS or the like for a predetermined time or a predetermined distance while the vehicle is traveling, and the position information of the measured current position is connected and specified. Is mainly taken.

  However, since the position information of the current position specified by GPS or the like is generally expressed by latitude and longitude and the number of digits is very large, the travel route is specified using the position information expressed by this latitude and longitude as it is. If information is to be generated, there is a problem that the amount of information becomes very large as the entire information for specifying the travel route.

For this reason, when generating information for specifying a travel route, various ideas have been made so far to compress information for specifying the travel route.
For example, in a certain device, position information is expressed in binary numbers, and information for specifying a travel route is compressed by sequentially taking the difference from the previous position.

Further, in Patent Document 1, information that specifies a travel route by using position information as road-shaped nodes, approximating the nodes connecting the nodes according to the road shape, and vectorizing the links connecting the nodes. Is compressed. Also in patent documents 2-4, the information which identifies a driving | running route is compressed by the method similar to this patent document 1.
JP2002-213980 JP2003-023357 JP 2004-354396 A JP 2005-338193 A

  By the way, with the spread of navigation devices and the like, a large amount of information specifying the travel route as described above is often recorded. This is due to the increasing use of information for specifying the driving route, such as route guidance when going to a place that was once visited later and information for specifying the driving route wirelessly. I think that the.

Therefore, further compression of the information specifying the travel route is required.
However, among the compression methods shown in the column of the prior art, in the former case, since the position information is represented by longitude and latitude with a large amount of information, the difference between the position information is compressed and compressed. However, there is a problem that the compression effect is not so great as to satisfy the above-described use.

  In the latter case, since the approximation is performed when the compression is performed, the approximated amount appears when the decompression is performed, and the travel route can be accurately reproduced even if the decompressed information is used. There is a problem that you can not.

  Accordingly, an object of the present invention is to provide a route information generation device that can compress the amount of information for specifying a route such as a travel route as compared with the conventional route and can accurately reproduce the route even after being decompressed. To do.

  The invention according to claim 1, which is an invention made to solve the above-described problem, is a route shown on a map (a traffic jam route indicating a traffic jam location when receiving a travel route, traffic jam information, etc., a route guide). This is a route information generation device that generates information for specifying a route guidance route for the vehicle.

In this route information generation device, first, the position specifying means specifies the positions of the passing points of a plurality of passing point routes on the route.
Next, in this route information generating device, the map is divided into a plurality of areas of a size that can identify the route on the map, and each area is numbered in advance, so that conversion means is used. The position information of the passing point specified by the position specifying means is converted into alternative position information indicating the number of the area including the passing point.

  Next, in this route information generating device, a route is determined based on uncompressed route information in which alternative position information corresponding to each passing point is arranged in the order in which the passing points are arranged from one end of the route toward the other end. Information to identify is generated.

  Specifically, for each of the alternative position information constituting the uncompressed route information by the route information generation means, a difference is taken between each alternative position information and the alternative position information immediately before the uncompressed information. The route information is converted into compressed route information, and the compressed route information is generated as information for specifying the route.

  In this way, if the route passing point is not specified by information representing the point like latitude and longitude, but specified by a number assigned to an area having a predetermined size area, it is necessary to specify the passing point. When the amount of information is reduced and information that identifies the route is formed, the alternative position information between the passing points is compressed by taking the difference, so it was created using latitude and longitude The amount of information can be greatly reduced compared to

  Moreover, since the compressed route information that is information for specifying the route created by the route information generation device is obtained by taking the difference between the alternative position information, if the compressed route information is decompressed, the decompressed information is decompressed. The route can be accurately reproduced using the alternative position information.

  Therefore, by using the route information generating device of the present invention, the amount of information specifying the route such as the travel route can be greatly reduced compared to the conventional one, and the route can be accurately reproduced even after being decompressed. it can.

  The size that can identify the route on the map is preferably about 30 m × 30 m, for example, but is not limited thereto. For example, the size of one side may be 3 m to 90 m. The area shape is preferably a quadrangle, but may be a polygon other than a quadrangle, such as a triangle, pentagon, or hexagon.

  By the way, when the travel route of the vehicle is recorded by attaching the route information generating device of the present invention to the vehicle or the like, the current position is specified as the position of the route passing point as described in claim 2. The position specifying means may be used as the position specifying means. By using the route information generating apparatus according to the second aspect, the amount of information specifying the travel route can be reduced, and the travel route can be accurately reproduced even after decompression.

When the current position specifying means is used, the current position may be specified every predetermined time. However, as described in claim 3, the current position may be specified for each predetermined travel distance.
Further, the map may be divided in any manner such as a mesh shape or a honeycomb shape as described in claim 4.

Next, the numbers assigned to the areas are preferably assigned so that the difference increases as the distance between the areas to be compared increases.
If the numbers are assigned in this way, the difference between the alternative position information indicating adjacent passing points can be reduced as compared with the case where the numbers are not assigned in this way, so that the information amount of the route information is further reduced. Can be compressed.

Next, the embodiment of the present invention described above will be described below.
[1 Navigation device]
Here, FIG. 1 is a block diagram of a navigation device mounted on the vehicle of the present embodiment. FIG. 2 is an explanatory diagram of the map code.

  As shown in FIG. 1, the navigation device 1 of the present embodiment includes a control circuit 2, a GPS receiver 3, a vehicle speed detector 4, an internal memory 5, a data transmitter / receiver 6, a map information storage unit 7, an operation unit 8, a monitor. 9 and other devices 10.

  The control circuit 2 communicates with the GPS receiver 3, the vehicle speed detector 4, the internal memory 5, the data transmitter / receiver 6, the map information storage unit 7, the operation unit 8, the monitor 9, and other devices 10 to generate route information generation processing to be described later. Various other processes are executed.

  The GPS receiving unit 3 receives position specifying signals transmitted from a plurality of GPS satellites, calculates a receiving position from the plurality of position specifying signals, and receives received position information indicating the received position from the control circuit 2. Is output.

The vehicle speed detector 4 detects the speed of the vehicle and outputs speed information of the detected vehicle speed to the control circuit 2.
The internal memory 5 is capable of storing and erasing information, and various information is stored and erased in accordance with various processes performed by the control circuit 2.

The data transmitter / receiver 6 wirelessly transmits various types of information to the outside based on processing in the control circuit 2 and inputs various types of information received wirelessly from the outside to the control circuit 2.
The map information storage unit 7 divides the digital map into a mesh, and expresses 6 to 14-digit number information indicating the number of each area corresponding to each mesh, and the position of each area in latitude and longitude. The position information is stored in association with each other.

  This number information uses what is called a map code (registered trademark) in this embodiment. As schematically shown in Fig. 2, this map code divides a digital map of Japan into approximately 1162 zones (1 zone = approximately 900 seconds x 900 seconds) in a mesh shape, and each zone is further meshed. Is divided into about 30 × 30 blocks (1 block = about 30 seconds (750 m) × 30 seconds in size), and each block is divided into about 30 × 30 units (1 unit = about 1 second) in a mesh shape. (20-30 m) × 1 second size), and further, each unit is divided into, for example, about 10 × 10 cores (1 core = about 3 m × 3 m size) in a mesh shape, and each zone, block, Units and cores are assigned zone numbers, block numbers, unit numbers, and core numbers.

  When this map code is used, the zone number, block number, unit number, and core number also serve as information indicating the position of the zone, block, unit, and core on the map, so the zone number, block number, unit number, By simply specifying the core number, you can specify the location of the zone, block, unit, or core.

In addition, since the size of a unit or a core is suitable for specifying a route on a map, the unit or core of this embodiment corresponds to the area of the present invention.
The operation unit 8 receives an operation of the operator with respect to the navigation device 1 and outputs operation information of the received operation to the control circuit 2.

The monitor 9 outputs a map and other images based on various processes performed by the control circuit 2.
The other device 10 is not particularly required in the processing described below, and is therefore other than that. However, the other device 10 is a device for performing functions other than the functions associated with the following processing of the navigation device 1, and is a specific example of the device. The type depends on the product.
[2 Route information generation processing]
Next, route information generation processing performed by the control circuit 2 of the navigation device 1 will be described.

  Here, FIG. 3 is an explanatory diagram of the route information generation process, (a) is a schematic diagram for explaining how to generate information indicating a travel route, and (b) is a flowchart of the route information generation process. It is. FIG. 4 is a schematic diagram showing (a) a correspondence table between position information of latitude and longitude and a map code, and (b) a data form.

In the following description, it will be assumed that the step numbers from the smallest to the largest are processed in order, except as otherwise described in the text.
This route information generation process is a process for recording a travel route of a vehicle using a map code.

  This route information generation process is started when a predetermined operation is performed on the operation unit 8, a power switch (not shown) of the navigation device 1 is turned on, or a vehicle engine is started. First, the process of S10 is executed. Is done.

In S <b> 10, position information on the current position of the traveling vehicle is input from the GPS receiver 3. At this time, the position information input from the GPS receiver 3 is represented by latitude and longitude.
In S12, using the map information storage unit 7, the position information input in S10 is converted into a map code corresponding to this position information (corresponding to alternative position information of the present invention).

  In S14, a process of determining whether or not the map code converted in S12 has been converted for the first time after starting the route information generation process is executed. If it is determined in this process that the data has been converted first (S14: YES), then S16 is executed.

  In S16, immediately after the start of the route information generation process, the map code converted in S12 is used as information indicating a travel route together with information indicating that this map code is a starting point ("0" in this embodiment). The process of storing in the internal memory 5 as it is is executed.

  In S18, a process for determining whether or not an operation for stopping the recording of the travel route has been performed on the operation unit 8 is performed. If it is determined in this process that an operation for stopping the recording of the travel route has been performed. (S18: YES), this route information generation process is terminated.

On the other hand, when it is determined that the operation for stopping the recording of the travel route is not performed on the operation unit 8 (S18: NO), the process of S19 is executed.
In S19, it is determined whether or not the vehicle has traveled a predetermined travel distance (for example, 100 m) after acquiring the position information in the process of S10 immediately before.

  If it is determined in this determination that the vehicle has not traveled the predetermined travel distance (S19: NO), the process waits. If it is determined that the vehicle has traveled the predetermined travel distance (S19: YES), the processing from S10 onward is executed again. Is done. The travel distance is calculated based on the position information input from the GPS receiver 3 and the speed information input from the vehicle speed detector 4.

  Then, when S10 is executed again, the position information is input from the GPS receiver 3, and in S12, the position information input in S10 is converted into a map code corresponding to this position information using the map information storage unit 7. (Corresponding to alternative information of the present invention). In S14, since the map code converted in S12 is already stored in the internal memory 5, it is determined that the map code is not converted first after starting the route information generation process. Next, S20 is executed.

  In S20, a difference calculation process is performed to obtain a difference obtained by subtracting the previous map code from the map code just acquired in order. Specifically, if the map code immediately after the start of the route information generation process is P0, and the map codes obtained thereafter are P1, P2,... P (n−1), Pn. Are equivalent), P1-P0, P2-P1,... Pn-P (n-1),. Then, assuming that ΔP1, ΔP2,..., ΔPn,... From the difference information obtained by sequentially obtaining the differences between the young map codes, each difference information is ΔP1 = P1-P0, ΔP2 = P2-P1,. Pn-P (n-1),...

  Next, in S16, based on the difference information obtained as described above in S20, as shown in FIG. 4B, the map code P0 stored in the internal memory 5 immediately after the start of the route information generation process is added. , .DELTA.P2,..., .DELTA.Pn,... Are sequentially added and stored in the internal memory 5 again. At this time, information stored in the internal memory 5 is information for specifying a travel route in the present embodiment. P0, P1, P2,... P (n-1), Pn... Correspond to uncompressed route information of the present invention, and P0, .DELTA.P1, .DELTA.P2,..., .DELTA.Pn,. It corresponds to.

  When the process of S16 is executed, the process of S18 is executed again. If it is determined in this process that an operation for stopping the recording of the travel route is performed (S18: YES), the route information generation process is performed. Is terminated.

Here, a specific example when the route information generation process is executed will be described.
For example, as shown in FIG. 4A, if the position information of P0 is 139 degrees 25 minutes 03 seconds 75 east longitude and 35 degrees 23 minutes 10 seconds 10 north latitude, for example, the map code is P0 = “15500303 * 75 ".

  Similarly, if the position information of the point P1 is 139 degrees 25 minutes 08 seconds 90 east longitude and 35 degrees 23 minutes 10 seconds 10 north latitude, the map code is P1 = “15500308 * 77” and the position information of the point P2 is 139 longitude 139 Assuming that the degree is 25 minutes 26 seconds 76 and north latitude 35 degrees 23 minutes 09 seconds 27, the map code can be expressed as P2 = “15500276 * 86”.

  Further, when the difference information is taken in S20, ΔP1 (P1−P0) = “1550030877” − “1550030375” = 502, and ΔP2 is (P2−P1) = “1550027686” − “1550030877” = − 3191. .

As described above, if the passing point of the travel route is expressed as a point using latitude and longitude, the amount of information increases due to the large number of digits, but the amount of information can be reduced by using a map code.
Also, if the difference between the map codes is taken and the information for identifying the travel route is indicated by the difference information, the amount of information for identifying the travel route can be reduced by simply using the map code. The amount of information specifying the travel route can be reduced.
[3 Defrosting process]
Next, information (corresponding to the compressed route information of the present invention) specifying the travel route formed by the difference information generated by the route information generation process described above is used as a map code data string (P0, P1, P2,. .., Pn,...) (Corresponding to the uncompressed route information of the present invention), so-called decompression processing will be described.

Here, FIG. 5 is a flowchart of the decompression process.
This decompression process is started when a predetermined operation is performed on the operation unit 8, and first, the process of S30 is executed.

In S30, a process of restoring the map code of each passing point from the travel route information is executed.
Specifically, processing for sequentially obtaining P1 = P0 + ΔP1, P2 = P1 + ΔP2,..., Pn = P (n−1) + ΔPn is executed. Next, S31 is executed.

  In S32, when the navigation device using the travel route information cannot use the map code, a process of calculating position information represented by representative latitude and longitude corresponding to the map code of each passing point is executed. This decompression process ends.

If a map code data string (P0, P1, P2,..., Pn,...) Decompressed in this way is used, a map showing the travel route is displayed on a monitor (not shown) provided in the navigation device 1. be able to.
[4 Features of the navigation device according to the embodiment]
In the navigation device 1 of the present embodiment, uncompressed route information (P0, P1,...) In which map codes corresponding to each passing point are arranged in the order in which the passing points are arranged from one end to the other end of the travel route. , Pn...), For each of the map codes constituting the uncompressed route information, a compressed route in which the uncompressed route information is compressed by taking a difference from the map code immediately preceding each map code. The information is converted into information (P0, ΔP1,..., ΔPn,...), And the compressed route information is generated as information for specifying the travel route (S20 to S16).

  In this way, instead of specifying the passing point of the travel route with the information indicating the point like latitude and longitude, if the number assigned to the area having a predetermined area is specified by the map code, that is, the passing point, The amount of information required to identify the travel route is reduced, and the information that identifies the travel route is compressed using the difference between the map codes between the passing points. The amount of information can be greatly reduced compared to

  Moreover, since the compressed route information, which is information specifying the travel route created by the navigation device 1, is a difference between the map codes, if the compressed route information is decompressed, the decompressed map is displayed. The driving route can be accurately reproduced using the code.

Therefore, when the navigation device 1 according to the present embodiment is used, the amount of information specifying the travel route can be greatly reduced as compared with the prior art, and the travel route can be accurately reproduced even after decompression.
[5 Correspondences between Embodiments and Invention Specific Items]
The GPS receiver 3 of the present embodiment corresponds to the position specifying means of the present invention, the control circuit 2 that executes the process of S12 is the converting means, and the control circuit 2 that executes the processes of S16 and S20 is the route information generating means. Equivalent to. In addition, the navigation device 1 of the present embodiment corresponds to the route information generation device and the first and second route display devices of the present invention.
[6 Other embodiments]
In the above embodiment, the passing point is specified for each predetermined traveling distance, but may be specified for each predetermined time.

  In the above embodiment, the travel route information may be communicated by the data transmitting / receiving unit 6. Since the travel route information of the above embodiment has a small amount of information, the travel route information can be smoothly communicated without causing communication congestion.

In the above embodiment, the information for identifying the travel route is compressed by taking the difference, but the compression rate can be further increased by further converting the information to binary number.
In the above embodiment, information for specifying a travel route is handled. However, for example, route information indicating a portion where a traffic jam occurs may be used. For route information indicating the traffic jam information, a route information generation process is performed on the road. It may be generated by being executed on the side, received by the navigation device 1, and a traffic jam route may be displayed based on this route information.

  The present invention is not limited to the above-described embodiment as long as it matches the gist of the invention described in the claims.

It is a block diagram of the navigation apparatus mounted in the vehicle of this embodiment. It is explanatory drawing of a map code. It is explanatory drawing of route information generation processing, (a) is a schematic diagram for demonstrating a mode that route information is produced | generated, (b) is a flowchart of route information generation processing. (A) Correspondence table of position information of latitude and longitude and map code, (b) A schematic diagram showing a data form. It is a flowchart of a decompression process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Navigation apparatus, 2 ... Control circuit, 3 ... GPS receiving part, 4 ... Vehicle speed detection part, 5 ... Internal memory, 6 ... Data transmission / reception part, 7 ... Map information storage part, 8 ... Operation part, 9 ... Monitor, 10 ... Other equipment

Claims (5)

A route information generation device for generating information for specifying a route shown on a map,
Position specifying means for specifying the position of each of a plurality of passing points on the route;
The map is divided into a plurality of areas of a size that can specify the route on the map, and the position information of the passing point specified by the position specifying means is assigned to each area in advance. Conversion means for converting into alternative position information indicating a number of the area including the passing point;
The uncompressed route information in which the alternative position information corresponding to each passing point is arranged in the order in which the passing points are arranged from one end of the route toward the other end is used as the alternative constituting the uncompressed route information. For each piece of location information, route information generating means for converting the compressed location information into a compressed route information by taking a difference from the alternative location information immediately before the alternative location information, and
With
A route information generating apparatus, wherein the compressed route information is generated as information for specifying the route. In the route information generating device according to claim 1,
The route information generating device, wherein the position specifying means is a current position specifying means for specifying a current position as a position of a passing point of the route. In the route information generating device according to claim 2,
The route information generating device, wherein the current position specifying means specifies the current position for each predetermined travel distance. In the route information generating device according to any one of claims 1 to 3,
The route information generating apparatus, wherein the map is divided into a mesh. In the route information generating device according to any one of claims 1 to 4,
The route information generating apparatus according to claim 1, wherein the number of each area is assigned such that the difference increases as the distance between the areas to be compared increases.