JP2001289651A - Navigation system, map matching method and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a navigation system capable of adequately correcting the own vehicle position on a running road. SOLUTION: GPS unit 14 acquires the present position of own vehicle according to received satellite radio waves. An image pickup unit 3 takes the surface images of the own vehicle running road one after another, including white lines. A white line monitor 17 measures the distance of the white line spacing according to the road surface image photographed by the pickup unit 3, and determines that the running load is of an expressway or public road type according to the measured distance. CPU 16 identifies the running road from map information stored on a disc according to the road type determined by the white line monitor 17, and corrects the present position acquired by the GPS unit 14. A monitor 2 displays a combined symbol mark showing the corrected present position on a map image according to the map information.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a navigation system which combines a symbol indicating the position of a vehicle with a map image and displays the symbol, and in particular, can appropriately correct the position of the vehicle on a traveling road. The present invention relates to a navigation system, a map matching method, and a recording medium.

[0002]

2. Description of the Related Art A conventional navigation system is mounted on a user's vehicle (hereinafter referred to as "own vehicle") and receives satellite radio waves by a predetermined GPS (Global Positioning System) unit or the like, and receives a satellite signal. Current position (own vehicle position)
To get. Then, a map image or the like centering on the own vehicle position is read from a disk or the like on which map information including map images and road information is recorded, and a map image combining symbols indicating the own vehicle position is displayed on a predetermined monitor. . By referring to the map image displayed on the monitor and the position of the own vehicle, the user recognizes the positional relationship between the vehicle that he or she drives and the surrounding roads, and is able to find the destination to which he or she should go without getting lost. You can drive the car.

[0003] As described above, such a navigation system converts a satellite wave transmitted from a GPS satellite into a GP signal.
Satellite navigation, which is received by an S unit or the like and calculates the position of the vehicle in accordance with the received satellite radio waves, is generally used. At present, this satellite navigation is generally expected to have an error of about several tens of meters. Further, in the satellite navigation, an even larger error may occur due to the influence of a receivable satellite position (satellite arrangement or the like) or a building around the own vehicle. For this reason, using the vehicle position obtained by satellite navigation as it is,
When a symbol is combined with a corresponding position on the map image, the symbol may not be located on the road due to an error that has occurred.

As a countermeasure, many navigation systems have a map matching function for correcting the position of the vehicle so that the vehicle is located on a target road. The map matching function appropriately corrects the position of the vehicle on the map image so as to be located on a nearby road in anticipation of the generated error by using, for example, a pattern matching method or a projection method. Since a navigation system having such a map matching function displays a map image in which symbols are synthesized on a predetermined road, it is possible to indicate a destination to which the user should go without causing confusion to the user.

[0005]

However, in the conventional navigation system, the position of the vehicle after map matching may not be correctly corrected on the road on which the vehicle is traveling. More specifically, in a state in which the own vehicle is traveling in an area where an expressway and a general road are vertically overlapped by an overpass or the like, or the vehicle is traveling in an area arranged in parallel, the navigation system determines which road Since it cannot be accurately determined whether the vehicle is traveling, the own vehicle position may be corrected on an incorrect road by map matching.

For example, even when the vehicle is traveling on a highway on an elevated road, the navigation system sometimes corrects the position of the vehicle on a general road under the elevated road by map matching. In this case, the navigation system erroneously recognizes that the vehicle is traveling on a general road, and instructs a right / left turn or the like that is impossible in reality. When such an erroneous instruction is given, the user may be surprised at an unexpected instruction and may make a wrong driving operation, which is extremely dangerous.

SUMMARY OF THE INVENTION The present invention has been made in view of the above situation, and appropriately corrects the position of a host vehicle on a traveling road when displaying a symbol indicating the position of the host vehicle on a map image. It is an object of the present invention to provide a navigation system, a map matching method, and a recording medium that can be used.

[0008]

In order to achieve the above object, a navigation system according to a first aspect of the present invention comprises: an image pickup unit for picking up a scenery image in a vehicle traveling direction including a road surface; The vehicle travels between the reference screen and the predetermined screen according to an image analysis unit that extracts a lane image drawn on the road surface from the landscape image of the time measured by the predetermined timer, and outputs a vehicle speed pulse indicating the vehicle speed. A travel distance calculation unit that calculates the travel distance of the vehicle that has been traveled, a lane image extracted by the image analysis unit, and a number of lanes that pass through the travel distance calculated by the travel distance calculation unit. It is characterized by including a determination unit and a storage unit that stores the type of the road determined by the road determination unit.

According to the present invention, the image pickup unit includes, for example, a camera or the like, and picks up a landscape image in the vehicle traveling direction including the road surface. The image analysis unit extracts a lane image drawn on a road surface from a landscape image captured at a time measured by a predetermined timer by the imaging unit. The travel distance calculation unit calculates the travel distance of the vehicle that has traveled between the reference screen and the predetermined screen according to the output of the vehicle speed pulse indicating the vehicle speed. The road determination unit determines the number of lanes passing according to the lane image extracted by the image analysis unit and the travel distance calculated by the travel distance calculation unit, and determines, for example, the type of an expressway or a general road.
The storage unit stores the type of the road determined by the road determination unit. By performing the map matching using the type of the road stored in the storage unit, the position of the own vehicle on the traveling road can be appropriately corrected.

[0010] To achieve the above object, a navigation system according to a second aspect of the present invention comprises a current position obtaining means for obtaining a current position of the own vehicle, a storage means for storing map information, and a self-position including a lane. Imaging means for sequentially capturing a road surface image on which a car is traveling; measuring means for measuring a distance between lanes according to the road surface image captured by the imaging means; and a traveling road according to the distance measured by the measuring means. Determination means for determining the type of the vehicle, and a correction for identifying a traveling road from the map information stored in the storage means according to the type determined by the determination means, and correcting the current position obtained by the current position obtaining means. Means, and display means for combining and displaying a symbol mark indicating the current position corrected by the correction means on a map image according to the map information stored in the storage means. Characterized in that it obtain.

According to the present invention, the current position obtaining means includes:
For example, it comprises a GPS unit or the like, and acquires the current position of the vehicle according to the received satellite radio waves. The storage unit stores the map information on a recording medium such as a disk, for example. The imaging means is, for example, a camera or the like, and sequentially captures images of the road surface on which the own vehicle including the lane is traveling. The measuring unit measures the distance between the lanes according to the road surface image captured by the imaging unit. The determining means determines, for example, the type of a running highway or a general road according to the distance measured by the measuring means. The correction unit specifies a traveling road from the map information stored in the storage unit according to the type determined by the determination unit, and corrects the current position acquired by the current position acquisition unit. The display unit combines the map image according to the map information stored in the storage unit with a symbol mark indicating the current position corrected by the correction unit, and displays the combined image. As a result, it is possible to appropriately correct the position of the own vehicle on the traveling road.

The measuring means sequentially specifies lane portions included in the road surface image picked up by the image pickup means, and measures the number of the specified lane portions within a predetermined time, and a vehicle speed indicating a vehicle speed. Data acquisition, travel distance measurement means for measuring the travel distance of the vehicle within a predetermined time according to the acquired vehicle speed data, the number of lane portions measured by the lane number measurement means, and the travel distance measurement means May be provided in accordance with the travel distance measured by the vehicle.

In order to achieve the above object, a map matching method according to a third aspect of the present invention includes a current position obtaining step of obtaining a current position of a vehicle, and a road surface image including a lane on which the vehicle is traveling. An image capturing step of sequentially capturing an image, a measuring step of measuring a distance between lanes according to a road surface image captured in the image capturing step, and determining a type of a traveling road according to the distance measured in the measuring step And determining the traveling road from the map information stored in the predetermined storage unit, and correcting the current position obtained in the current position obtaining step in accordance with the type of the type determined in the determining step. And a correcting step.

According to the present invention, the current position obtaining step obtains the current position of the own vehicle in accordance with, for example, the received satellite radio waves. The imaging step sequentially captures a road surface image in which the own vehicle including the lane is traveling. The measurement step measures the distance between the lanes according to the road surface image captured in the imaging step. The determining step determines the type of the traveling road according to the distance measured in the measuring step.
The correction step specifies a traveling road from the map information stored in the predetermined storage unit according to the type determined in the determination step, and corrects the current position acquired in the current position acquisition step. As a result, it is possible to appropriately correct the position of the own vehicle on the traveling road.

In order to achieve the above object, a recording medium according to a fourth aspect of the present invention comprises: a current position obtaining step of obtaining a current position of a vehicle; An image capturing step of capturing an image, a measuring step of measuring a distance between lanes according to the road surface image captured in the image capturing step, and determining a type of a traveling road according to the distance measured in the measuring step. A determining step of determining a traveling road from map information stored in a predetermined storage unit in accordance with the type determined in the determining step, and correcting the current position obtained in the current position obtaining step And recording a program for causing a computer to execute the map matching method having the steps.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A navigation system according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an example of a navigation system applied to an embodiment of the present invention. As shown in FIG. 1, the navigation system includes a device main body 1, a monitor 2, and an imaging device 3.

The main device 1 includes a flash memory 11 and
VRAM 12, RAM 13, GPS unit 14
, Gyro 15, CPU 16, white line monitoring unit 17
And a disk reproducing unit 18.
9.

The flash memory 11 has a flash type E
EPROM (Electrically Erasable Programmable RO
M) and the like, and stores past traveling information (moving locus, date and time information, etc.), landmark information set by the user, and the like.

The VRAM (Video RAM) 12 is a monitor 2
Is a display-only memory that stores a map image and the like that are the basis of the navigation screen displayed in the navigation screen.

A RAM (Random Access Memory) 13 is
The position information and CPU 1 acquired by the GPS unit 14
The current position information and the like corrected in step 6 are sequentially stored. Further, the RAM 13 stores a guidance route from the departure place to the destination.

A GPS (Global Positioning System) unit 14 tunes to satellite radio waves transmitted from a plurality of GPS satellites and received by a predetermined GPS antenna, despreads and demodulates each satellite radio wave, and converts a plurality of satellite reception signals. get. The GPS unit 14 generates position information including a latitude, a longitude, an altitude, and the like, based on a difference in arrival time of each satellite radio wave calculated according to each of the acquired satellite reception signals. The GPS unit 14 supplies the generated position information to the CPU 16 at every predetermined timing.

The gyro 15 measures the traveling direction of the own vehicle, and supplies angle information indicating an angle between the measured traveling direction and the reference direction to the CPU 16.

CPU (Central Processing Unit) 16
Controls the entire main device 1. Specifically, the CPU 16
Controls the disk reproducing unit 18 in accordance with the position information supplied from the GPS unit 14 and reads target map information and the like from the disk. Further, the current position of the own vehicle is corrected so as to be located on the target road in accordance with the position information supplied from the GPS unit 14, the determination signal supplied from the white line monitoring unit 17, and the like.

As shown in FIG. 2, the white line monitoring unit 17 includes an image analysis unit 41, a distance calculation unit 42, and a road determination unit 43. The image analysis unit 41 analyzes the image data sent from the imaging device 3, specifies a white line image (lane portion) included in the image data, and calculates the number of white lines specified within a certain time.

The manner in which the image analysis unit 41 calculates the number of white lines will be specifically described below with reference to FIG. Note that, as shown in FIG.
It is assumed that image data including the image of the white line 62 captured by the imaging device 3 is sequentially supplied to the image analysis unit 41 which is arranged on both sides of the (own vehicle).

The image analyzer 41 specifies a white line image (lane portion) as shown in FIG. 3B from the supplied image data. In addition, the image analysis unit 41 also determines a state that does not include a white line image as illustrated in FIG. Then, the image analysis unit 41 pulsates the presence or absence of the white line image in the image data supplied from the imaging device 3 as illustrated in FIG. The image analysis unit 41 calculates the number of white lines by counting pulses (presence or absence of white lines) within a predetermined time.

After calculating the number of white lines that have passed within the predetermined time, the image analysis unit 41 generates white line number data indicating the calculated number of white lines, and outputs the data to the road determination unit 43.
To supply.

Returning to FIG. 2, the distance calculation section 42 calculates the distance traveled by the own vehicle within a predetermined time using the vehicle speed pulse and the internal timer. That is, the distance calculation unit 42 calculates the travel distance corresponding to the number of white lines calculated by the image analysis unit 41. The distance calculation unit 42 generates distance data indicating the calculated travel distance, and supplies the generated distance data to the road determination unit 43.

The road determination unit 43 generates a determination signal indicating the type of the traveling road in accordance with the white line number data acquired from the image analysis unit 41 and the distance data acquired from the distance calculation unit 42.

Specifically, the road determination unit 43 calculates the length of the interval between the white lines according to the acquired white line number data and the distance data. Here, since the length of the interval between the white lines on the expressway is determined by the traffic regulations to be 20 m, the running road is either an expressway or a general road based on the calculated length of the interval between the white lines. Can be determined. When generating the determination signal indicating the type of the expressway or the general road, the road determination unit 43 supplies the generated determination signal to the CPU 16.

Returning to FIG. 1, the disk reproducing unit 18
Reproduces a disk such as a CD-ROM or a DVD (Digital Versatile Disk) on which map information including a map image and road information is recorded, and reads a target map image and the like from the disk. The disk reproducing unit 18 supplies the read map image and the like to the CPU 16.

The monitor 2 is a liquid crystal display (LCD).
play) or a CRT (Cathode Ray Tube), and is connected to the main device 1 via a predetermined signal line. The monitor 2 displays a navigation screen according to a map image or the like stored in the VRAM 12. The monitor 2 includes a touch sensor 21 and a remote control light receiving unit 22.

The touch sensor 21 is disposed on the front surface (on the display screen) of the monitor 2 and, when detecting a contact of a user's finger or the like, information such as a position on the screen where the contact is detected is detected by the CPU 16.
To supply.

The remote control light receiving section 22 receives a command signal or the like transmitted by an infrared signal or the like from a remote controller (remote controller) not shown, and supplies the received command signal and the like to the CPU 16.

Two image pickup devices 3 are installed at predetermined places of the vehicle, for example, near the bottoms of the left and right doors, and sequentially pick up images of a predetermined range including white lines picked up from the installation positions. The imaging device 3 generates image data of a captured image, and sequentially supplies the generated image data to the white line monitoring unit 17.

Hereinafter, the operation of the navigation system according to the embodiment of the present invention will be described with reference to the drawings. FIG. 4 is a flowchart for explaining the navigation processing performed by the CPU 16. FIG. 5 is a flowchart for explaining a white line monitoring process performed by the white line monitoring unit 17. FIG. 7 is a flowchart for explaining the map matching process in detail.

The navigation processing shown in FIG.
For example, the processing is started after a destination or the like is input from the user via the touch sensor 21 and a guidance route from the departure point to the destination is selected. The white line monitoring process shown in FIG. 5 starts in parallel with the start of the navigation process. Hereinafter, the navigation processing shown in FIG. 4 will be described.

First, the CPU 16 controls the GPS unit 14.
The current position of the own vehicle is acquired from such as (step S1). That is, the CPU 16 acquires the own vehicle position according to the position information generated by the GPS unit 14.

The CPU 16 has a disk reproducing unit 18
To read the target map information and the like recorded on the disk (step S2). That is, the CPU 16
A map image or the like within a predetermined range centered on the own vehicle position is read out via the disk reproducing unit 18.

The CPU 16 performs a map matching process (step S3). That is, the CPU 16 performs a map matching process of correcting the current position acquired in step S1 to a position on the traveling road in the map image. The details of the map matching process will be described later.

The CPU 16 draws a navigation image on the monitor 2 (step S4). That is, CPU1
6 generates a navigation image by combining the map image acquired in step S2 with a symbol mark indicating the current position corrected by the above-described map matching process,
The generated navigation image is displayed on the monitor 2.

The CPU 16 determines whether the vehicle has arrived at the destination (step S5). That is, the CPU 16
It is determined whether or not the vehicle has arrived at a preset destination. When determining that the vehicle has not arrived at the destination, the CPU 16 returns the processing to step S1 and returns to the above-described steps S1 to S1.
The process of S5 is repeatedly executed. On the other hand, when it is determined that the vehicle has arrived at the destination, the navigation processing ends.

As described above, the map matching process corrects the current position on the road on which the vehicle is traveling, and the monitor 2 displays a map image in which symbols indicating the corrected vehicle position are combined.

Next, the white line monitoring process shown in FIG. 5 will be described. This white line monitoring process is sequentially executed in parallel with the above-described navigation process.

First, the image analyzer 41 acquires the image data sent from the image pickup device 3 (step S11). That is, the image analysis unit 41 acquires image data including a white line image (lane portion) captured by the imaging device 3.

The image analysis section 41 specifies the white line image and calculates the number of white lines passed within a predetermined time (step S).
12). That is, the image analysis unit 41 calculates the number of white lines by pulsing the presence or absence of a white line image in the image data supplied from the imaging device 3 and counting the pulses (presence or absence of white lines) within a predetermined time. Image analysis unit 4
After calculating the number of white lines, 1 generates white line number data indicating the calculated number of white lines and supplies the data to the road determination unit 43.

On the other hand, the distance calculation unit 42 calculates the distance traveled by the own vehicle within a predetermined time according to the vehicle speed pulse or the like (step S13). That is, the distance calculation unit 42 uses the vehicle speed pulse and the internal timer to calculate the travel distance corresponding to the number of white lines calculated by the image analysis unit 41. The distance calculation unit 42 generates distance data indicating the calculated travel distance, and supplies the generated distance data to the road determination unit 43.

The road determination unit 43 calculates the length of the white line interval according to the white line number data and the distance data (step S14). That is, the road determination unit 43 compares the white line number data acquired from the image analysis unit 41 with the distance calculation unit 42.
Then, the length of the interval between the white lines is calculated according to the distance data acquired from.

The road determination section 43 determines whether or not the calculated white line interval length is substantially equal to 20 m (step S15). That is, the road determination unit 43 determines whether or not the calculated white line interval length is substantially equal to the white line interval length 20 m defined on the expressway.

The road determination unit 43 determines that the length of the white line interval is 20
If it is determined that it is not equal to m, a determination signal indicating that the vehicle is traveling on a general road is supplied to the CPU 16 (step S1).
6).

On the other hand, if it is determined that the length of the white line interval is substantially equal to 20 m, the road determination unit 43 supplies a determination signal to the effect that the vehicle is traveling on the expressway to the CPU 16 (step S17). After supplying the determination signal to the CPU 16, the process returns to step S11, and the above-described steps S11 to S11 are performed.
Step 17 is repeatedly executed.

As described above, in the white line monitoring process, it is determined from the length of the white line interval whether the running road is an expressway or a general road, and the determination result is used as a determination signal as a determination signal.
Supply to U16 sequentially.

Next, the map matching processing shown in FIG. 7 will be described. This map matching process is a process called from step S3 in the above-described navigation process.

First, the CPU 16 obtains layout information of an expressway, a general road and the like corresponding to the position of the vehicle (step S31). That is, the CPU 16 reads the map information recorded on the disk, and acquires the layout information of the expressway, the general road, and the like within a predetermined range centering on the own vehicle position according to the road information included in the map information.

When acquiring the layout information, the CPU 16 determines whether or not the expressway and the general road are parallelly arranged (step S32). Specifically, C
The PU 16 determines whether or not the expressway 51 and the general road 52 are arranged within a predetermined distance in parallel as shown in FIGS. 6A and 6B. Note that the CPU 16 determines that the highway 51 and the general road 52 are not always parallel as shown in FIG. 6C and FIG. It is also determined that they are arranged in parallel even when they are arranged in.

On the other hand, FIG.
As shown in (f) and FIG. 6 (g), when the general roads 52 are arranged in parallel with each other or when there are very few parallel places, it is determined that they are not arranged in parallel.

If the CPU 16 determines that they are not arranged in parallel, the process proceeds to step S34. on the other hand,
If it is determined that they are arranged in parallel, the white line monitoring unit 17
(Step S3)
3). That is, the CPU 16 refers to the determination signal indicating the type of the road and acquires whether the traveling road is an expressway or a general road.

The CPU 16 corrects the position of the own vehicle so as to be located on the corresponding road by a pattern matching method or the like (step S34). At this time, when the determination signal is referred to in step S33, the road on which the vehicle is traveling is specified according to the determination signal, and the own vehicle position is correctly corrected so as to be located on the road on which the vehicle is traveling. After finishing the map matching process, the CPU 16 returns the process to the navigation process (step S4) shown in FIG.

As described above, even when the expressway and the general road are arranged in parallel or the like, map matching is performed while discriminating the type of the road on which the vehicle is traveling. Can be improved. As a result, when combining and displaying the symbol indicating the vehicle position on the map image, the vehicle position can be appropriately corrected on the traveling road.

In the above embodiment, the length of the interval between white lines (lanes) is measured in accordance with the captured image data, and whether the road on which the vehicle is traveling is an expressway or a general road is determined. However, the method of determining the expressway or the like is arbitrary. For example, instead of taking an image of the vicinity of the road surface with the imaging device 3, a landscape image around the own vehicle is captured, and from the captured landscape image, the road on which the vehicle is traveling is an expressway or a general road. It may be determined whether there is.

More specifically, the main device 1 includes a signal monitoring unit instead of the white line monitoring unit 17. The imaging device 3 is arranged near the windshield in the vehicle, and sequentially captures a landscape image at a predetermined angle above the front of the vehicle.
The signal monitoring unit sequentially acquires image data including a landscape image supplied from the imaging device 3 and determines whether or not the image data includes an image of a traffic light. If the signal monitoring unit determines that the image of the traffic light is not included while traveling the predetermined distance or more, the signal monitoring unit supplies the CPU 16 with a determination signal indicating that the traveling road is an expressway. When it is determined that an image of a traffic light is included, a determination signal indicating that the road on which the vehicle is traveling is a general road is sent to the CPU 16.
To supply.

Also in this case, when the highway and the general road are arranged in parallel or the like, the CPU 16 specifies the road on which the vehicle is traveling in accordance with the judgment signal referred to, and positions the own vehicle on the road on which the vehicle is traveling. Correct so that As a result, when combining and displaying the symbol indicating the vehicle position on the map image, the vehicle position can be appropriately corrected on the traveling road.

The navigation system according to the embodiment of the present invention can be realized by using a general computer system without using a dedicated system. For example, a navigation system that executes the above-described processing is installed in a computer by installing the program from a medium (a floppy (registered trademark) disk, a CD-ROM, or the like) storing the program for executing any of the above. can do.

A method for supplying a program to a computer is arbitrary. For example, the information may be supplied via a communication line, a communication network, a communication system, or the like. As an example, a bulletin board (BB) of a communication network
The program is posted on S) and distributed via a network. And start this program, O
Under the control of S, the above-described processing can be executed by executing the program in the same manner as other application programs.

[0065]

As described above, according to the present invention,
When the own vehicle position is combined with the map image and displayed, it is possible to appropriately correct the position on the target road.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an example of a configuration of a navigation system according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating an example of a configuration of a white line monitoring unit.

3A is a schematic diagram illustrating a state in which an imaging device arranged in a vehicle captures a white line, FIG. 3B is a schematic diagram of image data indicating an end of the white line, and FIG. Is a schematic diagram of image data showing intervals of white lines, and (d) is a schematic diagram for explaining how to pulse the presence or absence of a white line.

FIG. 4 is a flowchart illustrating a navigation process according to the embodiment of the present invention.

FIG. 5 is a flowchart illustrating a white line monitoring process according to the embodiment of the present invention.

6 (a) to 6 (g) are schematic diagrams for explaining an arrangement relationship between an expressway and a general road.

FIG. 7 is a flowchart illustrating a map matching process according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main apparatus 2 Monitor 3 Imaging device 11 Flash memory 12 VRAM 13 RAM 14 GPS unit 15 Gyro 16 CPU 17 White line monitoring part 18 Disk reproduction unit 19 Bus 21 Touch sensor 22 Remote control light receiving part

Claims (5)

[Claims] An image capturing section for capturing a landscape image of a vehicle traveling direction including a road surface, and a lane image drawn on a road surface is obtained from the landscape image captured by the image capturing section and measured by a predetermined timer. An image analysis unit to be extracted, a travel distance calculation unit that calculates a travel distance of a vehicle that has traveled from a reference screen to a predetermined screen according to an output of a vehicle speed pulse indicating a vehicle speed, and a lane image extracted by the image analysis unit. A road determination unit that determines the number of lanes according to the travel distance calculated by the travel distance calculation unit and determines the type of road; and a storage unit that stores the type of road determined by the road determination unit. A navigation system comprising: 2. A current position obtaining means for obtaining a current position of the own vehicle, a storage means for storing map information, an image pickup means for sequentially picking up a road surface image on which the own vehicle including a lane is traveling, and the image pickup means According to the road surface image captured by, measuring means for measuring the distance of the lane interval, according to the distance measured by the measuring means, determining means for determining the type of road traveling, according to the type determined by the determining means, A correcting means for specifying a traveling road from the map information stored in the storage means and correcting the current position obtained by the current position obtaining means; and a map image according to the map information stored in the storage means. A display unit that combines and displays a symbol mark indicating the current position corrected by the correction unit. 3. The lane number measuring means for sequentially specifying lane portions included in a road surface image picked up by the image pick-up means, and measuring the number of the specified lane portions within a predetermined time, A traveling distance measuring unit for measuring a traveling distance of the vehicle within a predetermined time according to the acquired vehicle speed data, and a number of lane portions measured by the lane number measuring unit, and the traveling distance. The navigation system according to claim 2, further comprising: a lane interval measuring unit that measures a distance of a lane interval drawn on a traveling road surface according to the traveling distance measured by the measuring unit. 4. A current position obtaining step for obtaining a current position of the own vehicle, an image capturing step for sequentially capturing a road surface image of the own vehicle including a lane in which the own vehicle is traveling, and a road surface image captured in the image capturing step. A measuring step of measuring a distance between lanes, a determining step of determining a type of a traveling road according to the distance measured in the measuring step, and a predetermined storage in accordance with the type determined in the determining step. And a correction step of correcting a current position acquired in the current position acquisition step by identifying a traveling road from the map information stored in the section. 5. A current position obtaining step for obtaining a current position of the own vehicle, an image capturing step for sequentially capturing a road surface image in which the own vehicle including a lane is traveling, and a road surface image captured in the image capturing step. A measuring step of measuring a distance between lanes, and a determining step of determining a type of a traveling road according to the distance measured in the measuring step;
In accordance with the type determined in the determination step, a traveling step is specified from map information stored in a predetermined storage unit, and a correction step of correcting the current position acquired in the current position acquisition step is provided. A computer-readable recording medium that records a program for causing a computer to execute the map matching method.