JPH08335036A - Navigation device - Google Patents

Abstract

PURPOSE: To provide a navigation device in which map image of a wide range can be contracted and displayed without scrolling the display image or changing the scale. CONSTITUTION: Map data are stored in a map data recording medium 2, and the present position of a vehicle is measured by a present position measuring part 1. The map data including the present position of the vehicle is read from the map data recording medium 2 by a map data reading part 3. From the read data, a picture element group containing at least the picture elements of a prescribed number-fold number larger than 1 of the picture element number indicatable on the display screen of a display part 10 at once is generated by a microcomputer 7, and stored in a map data accumulating RAM 4. From this picture element group, the number of picture elements indicatable on the display screen at once is selected by the microcomputer 7 while subtracting the picture elements at the interval determined by the prescribed number. The selected picture element group is stored in a drawing RAM 5. The stored picture element group is converted into an image signal by a drawing processing part 6, and this image signal is outputted to the display screen of the display part 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a navigation device mounted on a vehicle and displaying the current position of the vehicle on a display screen together with a map image, and more particularly to scrolling (moving) of the display screen by a user and map image The present invention relates to a navigation device suitable for displaying a wide range of map images without changing the scale.

[0002]

2. Description of the Related Art As a conventional system for displaying a map image, there is a system described in JP-A-6-110998. This is because it stores map data related to a detailed map image in a narrow range in which place names and roads are shown in detail, and a detailed map image is displayed on the display screen based on the stored map data, and a map of a wide range is displayed. This is a method in which the user scrolls the display screen when viewing the image.

Further, in various recently proposed navigation devices, map data relating to a detailed map image in a narrow range in which place names and roads are shown in detail, and a wide range of rough outlines in which only main place names and roads are shown. A plurality of map data having different scales, including map data relating to various map images, are stored, the scale is designated by the user, the map data having the designated scale is selected, and the map image is selected based on the selected map data. Is displayed on the display screen.

[0004]

In the technique described in the above publication among the above-mentioned conventional techniques, the user scrolls the display screen in an attempt to find a destination while displaying a detailed map image on the display screen. You may have to do it. In this case, the user has to perform an operation such as pressing and holding the scroll button.
At this time, it is necessary to keep looking at the display screen until the destination is displayed, or to see it frequently. For this reason,
The operation is time-consuming, and if the vehicle is operated while driving, attention may be diverted from the driving operation.

Further, when a rough map image of a wide range is displayed by changing the scale, there is a problem that the detailed information of the place name and the road cannot be displayed.

It is an object of the present invention to reduce a detailed map image in a wide range and display it on a display screen, so that a detailed geographical name in a wide range can be displayed without scrolling the display screen and without changing the scale. It is to be able to confirm information such as roads at a glance.

[0007]

In order to solve the above-mentioned problems, according to the present invention, in a navigation device mounted on a vehicle and displaying the current position of the vehicle together with a map on a display screen, Current position measuring means for measuring the current position, map data storage means for storing vector data representing the road shape in the map, and vector data including the current position of the vehicle measured by the current position measuring means. Based on the map data reading means for reading from the map data storing means and the vector data read by the map data reading means, the number of pixels that can be displayed at one time on the display screen is more than 1. Generating means for generating a data group including at least display information corresponding to a large predetermined number of pixels, and data generated by the generating means. First storage means for storing the data group,
From the data group stored in the first storage means, only display information of an amount that can be displayed on the display screen at a time is displayed at intervals determined by the predetermined number. Means for selecting by thinning, second storing means for storing the data group selected by the selecting means, and an image represented by the data group stored in the second storing means are displayed. Display means for outputting to the screen.

Further, in a navigation device mounted on a vehicle and displaying the current position of the vehicle together with a map on a display screen, a current position measuring means for measuring the current position of the vehicle and a road shape in the map are displayed. Map data storage means for storing vector data representing the map data, and map data read means for reading vector data including the current position of the vehicle measured by the current position measurement means from the map data storage means; First storage means for storing the vector data read by the reading means, and a number of pixels that can be displayed on the display screen at one time based on the vector data stored in the first storage means. A data group including at least display information corresponding to a predetermined number of pixels larger than 1 is generated, and the generated data group is Control means for selecting only the amount of display information that can be displayed on the display screen at one time by thinning out data at intervals determined according to the predetermined number, and the control means. It is also possible to have a second storage means for storing the data group and a display means for outputting an image represented by the data group stored in the second storage means on the display screen.

[0009]

In the navigation device mounted on the vehicle and displaying the current position of the vehicle together with the map on the display screen, first, vector data representing the road shape in the map is stored. Next, the current position of the vehicle is measured, and the vector data including the measured current position of the vehicle is read out. Based on the read vector data, the number of pixels that can be displayed at one time on the display screen is 1
A data group including at least display information corresponding to a predetermined multiple of the larger pixels is generated, and the generated data group is stored. From the stored data group, only the amount of display information that can be displayed at once on the display screen is selected by thinning out the data at intervals determined according to the predetermined number, The selected data group is stored. An image represented by the stored data group can be output to the display screen.

Further, in a navigation device mounted on a vehicle and displaying the current position of the vehicle together with a map on a display screen, first, vector data representing a road shape in the map is stored. Next, the current position of the vehicle is measured, vector data including the measured current position of the vehicle is read, and the read vector data is stored. Generating a data group including at least display information corresponding to a predetermined number of pixels larger than one, which is the number of pixels that can be displayed at one time on the display screen, based on the stored vector data; From the generated data group, only the amount of display information that can be displayed at one time on the display screen is displayed at intervals determined according to the predetermined number.
The data is selected by thinning out the data and the selected data group is stored. An image represented by the stored data group can be output to the display screen.

[0011]

FIG. 1 shows an embodiment of the present invention.

The navigation device of FIG. 1 has a current position measuring means 1, a map data recording medium 2, a map data reading means 3, and a random access memory 4 for storing map data.
(Map data storage RAM 4), drawing random access memory 5 (drawing RAM 5), drawing processing unit 6, microcomputer 7 (microcomputer 7), control program storage unit 8, drawing process switching control unit 9, and display means 10. The microcomputer 7 controls the entire navigation device via the control bus and the data bus according to the control program stored in the control program storage unit 8.

In FIG. 1, the microcomputer 7 controls the map data reading means 3 in accordance with the data obtained by measuring the current position of the vehicle by the current position measuring means 1, and the road in the map including the measured current position. The vector data representing the shape is read from the map data recording medium 2. The microcomputer 7 converts the read vector data into dot data, and temporarily stores it in the map data storage RAM 4.

Next, according to an instruction from the microcomputer 7, a specific portion of the data stored in the RAM 4 for storing map data, that is, the data of the range displayed on the display screen of the display means 10 is read out, and is read into the drawing RAM 5. Remembered. The drawing processing unit 6 converts the data stored in the drawing RAM 5 into an image signal and outputs the image signal to the display screen of the display unit 10, thereby, for example, a map including the current position of the vehicle as shown in FIG. The image is displayed on the display screen of the display means 10. In the map image of FIG. 2, a road and a park are shown, and the current position of the vehicle is shown by a triangle mark.

In the above description, when there is no instruction from the drawing process switching control section 9, the microcomputer 7 has a range m corresponding to one screen of the display screen of the display means 10 as shown in the image of FIG. Data of pixels × n rows are continuously read and stored in the drawing RAM 5. On the other hand, when an instruction is input from the drawing process switching control unit 9, the microcomputer 7 as shown in the image of FIG. 4, data in a wider range than one screen of the display screen of the display unit 10, for example, 2
Data for m pixels × 2n rows is read. Here, the microcomputer 7 controls the reading in this case not to be continuous as described above but to be performed every other column and every other row as shown in FIG. 5, for example. That is, RA for storing map data
R for drawing by intermittently reading the data stored in M4
Store in AM5.

By the control described above, compared with FIG. 2, which is a map image in which data is continuously read out from the RAM 4 for storing map data, the map image has two vertical and horizontal directions.
It is possible to reduce and display the map image in the range of double the length, that is, in the range of four times as shown in FIG.

Further, when the microcomputer 7 controls to read data from the RAM 4 for storing map data as shown in FIG. 7 so as to read two columns out of three columns and two rows out of three rows, a map image is displayed. 1.5 times the length in both the vertical and horizontal directions, that is, 2.2 in the case of FIG.
It is possible to reduce and display the map image in the range of 5 times.

In the above description, an example of displaying the map image in the range of 4 times or 2.25 times is shown, but the map image in the range other than the above is changed by changing the interval of reading the data from the map data storage RAM 4. Needless to say, can be displayed reduced.

Further, in the above description, an example of intermittently reading the data from the map data storage RAM 4 has been shown, but the data is continuously read from the map data storage RAM 4 and input to the drawing RAM 5. The same effect can be obtained by controlling only the desired data to be input.

Further, in the above description, the microcomputer 7 converts the vector data read from the map data recording medium 2 into dot data and stores the dot data in the map data storage RAM 4. Vector data read from the medium 2 is stored in the map data RAM 4
The microcomputer 7 may convert the vector data into dot data and input the vector data to the drawing RAM 5 continuously or intermittently.

As described above, according to the present invention, it is possible to reduce the size of a map image in a wider range compared to the normal display as shown in FIG. 2 without scrolling the display screen or changing the scale.

[0022]

As described above, according to the present invention, a navigation device can reduce and display a wide range of map images without scrolling the display screen or changing the scale of the map. it can.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an example of a display screen.

FIG. 3 is an explanatory diagram showing an example of a data array of a drawing RAM 5.

FIG. 4 is an explanatory diagram showing an example of a data array of a RAM 4 for storing map data.

FIG. 5 is an explanatory diagram showing an example of a data array of a drawing RAM 5;

FIG. 6 is an explanatory diagram showing an example of a display screen.

FIG. 7 is an explanatory diagram showing an example of a data array of a drawing RAM 5.

[Explanation of symbols]

1 current position measuring unit 2 map data recording medium 3 map data reading unit 4 random access memory for storing map data (RAM for storing map data) 5 random access memory for drawing (RAM for drawing) 6 drawing processing unit 7 microcomputer (microcomputer) ) 8 control program storage unit 9 drawing process switching control unit 10 display unit

Claims (2)

[Claims] 1. A vehicle mounted on a vehicle, the current position of the vehicle is
In a navigation device displaying together with a map on a display screen, a current position measuring means for measuring the current position of the vehicle, a map data storage means for storing vector data representing a road shape in the map, and the current position measuring means. On the display screen based on the vector data read by the map data reading means for reading the vector data including the current position of the vehicle measured by the map data storage means, Generating means for generating a data group including at least display information corresponding to a predetermined number of pixels larger than one, which is the number of pixels that can be displayed at one time, and data generated by the generating means. A first storage means for storing a group and a group of data stored in the first storage means, which are displayed on the display screen at a time. Means for selecting only the amount of display information that can be reproduced by thinning out the data at intervals determined according to the predetermined number, and a second means for storing the data group selected by the selecting means. A navigation device comprising: a storage means; and a display means for outputting an image represented by the data group stored in the second storage means to the display screen. 2. A vehicle mounted on a vehicle, the current position of the vehicle,
In a navigation device displaying together with a map on a display screen, a current position measuring means for measuring the current position of the vehicle, a map data storage means for storing vector data representing a road shape in the map, and the current position measuring means. Map data reading means for reading vector data including the current position of the vehicle measured by the map data storing means, and first storing means for storing the vector data read by the map data reading means. And, based on the vector data stored in the first storage means, display information corresponding to at least a predetermined number of pixels larger than one that can be displayed at one time on the display screen. A data group containing the generated data is generated, and the generated data is generated.
Control means for selecting, from among the data group, only display information in an amount that can be displayed on the display screen at a time by thinning out data at intervals determined according to the predetermined number; Second storage means for storing the data group selected by the means, and display means for outputting an image represented by the data group stored in the second storage means to the display screen. Navigation device.