JPH08212332A - Image display device - Google Patents

Abstract

PURPOSE: To obtain an image display device which can generate an image with a small amount of data in a short time and display it by holding an image in an image data storage means as image data divided into several blocks including data of the image itself. CONSTITUTION: The image display device has an image data ROM (image data storage means) 11 which holds image data regarding an image to be displayed, an image controller(image write control means) 12 which inputs image data from the image data ROM 11, temporarily holds screen information that can immediately be displayed as a frame buffer, and outputs it as image information, and a display device (display means) 15 which inputs the image information from the image controller 12 and displays its image. The image data ROM 11 holds the image data as image data divided into several blocks including the data of the image itself.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display device,
Particularly, it relates to a device for displaying a large image.

[0002]

2. Description of the Related Art In an on-vehicle navigation device as an image display device, for example, to guide a driver to a route, when a vehicle approaches a point such as an intersection, a route guidance is displayed on the screen of the display to inform the driver of the direction of travel. There is one that displays an arrow as an image (see, for example, Japanese Patent Laid-Open No. 6-341850). FIG. 5 is an enlarged view for explaining the structure of the arrow A, and the displayed arrow A has a width of 40 bits (x0 to x).
39) x vertical 35 bits (y0 to y34) matrix. Therefore, the arrow A requires an image data amount of 1400 bits.

[0003]

With such a configuration, although the data itself indicated by the arrow A requires only 353 bits in total (hatched portions in FIG. 5), it requires image data of 1400 bits. It is a very inefficient one with a utilization rate of 25% (353/1400). Then, in the case of displaying based on such image data, there is a problem that the screen creation time becomes long.

Further, as shown in FIG. 6, when an auxiliary line B is displayed as another image near the arrow A, the auxiliary line B is 40 bits wide (x0 to x39) × 15 bits vertical (y25
~ Y39), but part of it overlaps the matrix of arrow A. In this matrix, it is necessary to have not only the data of the auxiliary line B but also the image data of the overlapping point C of the arrow A. The image data of the overlapping point C should be provided in both the arrow A and the auxiliary line B. Therefore, it is still inefficient. And naturally, the screen creation time also becomes long.

[0005]

SUMMARY OF THE INVENTION In view of the above problems, the present invention provides an image data storage means for holding image data relating to an image to be displayed, and the image data from the image data storage means is input and immediately displayed. Image writing control means for temporarily storing and holding possible screen information as a frame buffer and outputting as image information, and display means for inputting the image information from the image writing control means and displaying the image, The image data storage means holds the image data divided into a plurality of blocks including the data of the image itself.

Further, according to the present invention, the image data storage means holds the image data divided into a plurality of blocks of a minimum size including the data of the image itself.

[0007]

The image data storage means holds the image data divided into a plurality of blocks including the data of the image itself so that an image can be created and displayed in a short time with a small amount of data. The device can be realized. In particular, when the image data divided into the blocks has a minimum size including the data of the image itself, the effect is great when a large image is displayed.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An image display device and an image display method according to the present invention will be described below based on an embodiment in which the vehicle-mounted navigation device shown in FIGS.

In the embodiment, the azimuth sensor 1a is the traveling azimuth of the vehicle according to the geomagnetism, the angular velocity sensor 1b is the angular velocity,
The distance sensor 1c detects traveling distance, respectively, and these sensors 1a to 1c constitute a traveling state detection sensor group 1, and a GPS (Global Positioning System) 2 detects the current position of the vehicle from latitude and longitude information. The detection signal from the traveling state detection sensor group 1 and the position signal from the GPS 2 are detected by the interface 3 that performs A / D conversion and the like.
Is supplied to the CPU 4 which calculates the amount of movement based on the data from the interface 3 and performs various processes.

In the CPU 4, RAM 5 and C in which information necessary for executing the program is written and read.
A ROM 6 in which various processing programs of the PU 4 and necessary information are stored in advance, a storage device 7 including a storage medium such as a CD-ROM or an IC card in which digitized map information is stored, a key operation by a user, for example, An input device 8 including an input operation member such as a keyboard for sending various commands such as route setting to the CPU 4 is connected. Also, C
A buffer memory 9 which is composed of V-RAM or the like for graphic data of map information and temporarily stores and holds screen information which can be immediately displayed as a frame buffer in response to a command from the PU 4.
A graphic controller 10 for drawing and outputting as graphic information is connected. An image data ROM (image data storage means) 11 that stores and holds image data relating to images such as route guidance marks,
The image data to be displayed according to the command from the CPU 4 is VR
An image controller (image writing control means) 12 which is composed of AM or the like and which temporarily stores and holds screen information that can be displayed immediately as a frame buffer and outputs it as image information is connected. And these constitute the system controller 13 as a whole.

Reference numeral 14 denotes a display device for displaying map information, which is located in front of the user such as the center console and for displaying map information, and 15 is located in front of the driver such as the center console. It is a display device (display means) for route guidance display including an LCD or the like for displaying an image such as a route guidance mark. That is, when the display device 14 performs a predetermined display according to the graphic information a from the graphic controller 10 according to a command from the CPU 4 and approaches a point such as an intersection that requires the determination of the traveling direction, the CP
The display device 15 displays according to the image information b from the image controller 13 by a command from U4 by a method described later.

Next, an image display method of the display device 15 for route guidance display will be described by taking as an example the case where the display device 15 displays the arrow A in FIG. 2 as an image.

The image data ROM 11 stores the image data of the arrow A in five blocks A1 (address 00 in FIG. 2), A2 (same 01) and A3 in 8 bits in the x direction in FIG.
In (02), A4 (03) and A5 (04), the length of the y method in FIG. 2 is determined so that each block A1 to A5 has the minimum size including the data of the arrow A itself. The blocks A1 to A5 are divided and held, and the blocks A1 to A5 have addresses 00 to 0B, 01 to 12, 04 to 17, and 1 in FIG. 2, respectively.
The data of 0 to 1F and the data of 18 to 22 are held.

Specifically, the blocks A1 to A5 shown in FIG.
Are sequentially rearranged (FIG. 3 (a)), and bits with arrow A and bits without arrow A are separated by "1" and "0" (FIG. 3).
(B)), this is coded in hexadecimal, and at the beginning of each block A1 to A5, an area of initial data indicating the size of the block and the screen start position is added (FIG. 3 (c)). . For example, regarding the block A1, the address 00 is 12 of the addresses 03 to 0E which is the size of the data.
The address "01" has "0.C", the address 01 has the screen start position of the block A1 as "0. 0" in the x direction 00 in FIG. Also,
Regarding the block A2, the address 0F is "1.2" that indicates 18 addresses 12 to 23, which are the data size, and the address 10 is the screen start position of the block A2, and the x direction 01 in FIG. 2 is "0.1". , Address 11 has y direction 01 as “0.1”. Then, in the image data ROM 11, the data of FIG. 3C corresponds to 8 bits and is "0".
It is stored and held as "1" (FIG. 3 (d)).

An area corresponding to the screen of the display device 15 shown in FIG. 2 is prepared in the V-RAM (not shown) in the image controller 12, and the CPU 4 sets "0.0" in all the areas. To write and clear (Fig. 4
(A)). Next, the CPU 4 obtains, as image data, each data and screen start position (x, y) of the five blocks A1 to A5 relating to the arrow A of the image data ROM 11, and based on these image data, the arrow A of the V-RAM is displayed. Data is written (FIG. 4 (b)).

Then, the image controller 12 outputs the image information based on the written arrow A to the display device 15, so that the display device 15 displays the image as shown in FIG.

In this image display method, the image data amount of arrow A is 616 bits (total bits of blocks A1 to A5)
And it will be about 44% of the conventional example, which will be extremely small. In addition, the utilization rate has improved significantly to about 57% (about 25% in the conventional example),
Since the image data amount of the arrow A is smaller than that of the conventional example, the writing time is shortened and the display can be updated in a short time. Especially, the effect is great in a device that displays a large image.

Even when a plurality of images as shown in FIG. 6 are displayed close to each other, each image is divided into blocks having a minimum size including the data of the image itself, and this block is divided into blocks. By storing the image data for each, it is possible to reduce duplicate image data,
The total amount of image data can be reduced.

Further, in the above-mentioned embodiment, the case of dividing every 8 bits has been described, but it may be finely divided (for example, 4 bits) or conversely divided largely (for example, 16 bits).

[0020]

According to the present invention, image data storage means for holding image data relating to an image to be displayed, and screen information which can be displayed immediately by inputting the image data from the image data storage means are temporarily stored as a frame buffer. Image writing control means for holding and outputting as image information, and display means for displaying the image by inputting the image information from the image writing control means, the image data storage means includes the image itself. The image data is held as image data divided into a plurality of blocks including the above data, and the amount of image data is extremely small. Further, the utilization rate is greatly improved, and the image data amount is smaller than that in the conventional example, so that the writing time is shortened and the display can be updated in a short time.

Further, according to the present invention, the image data storage means displays a large image by holding the image data as image data divided into a plurality of blocks having a minimum size including the data of the image itself. The effect is great when you do.

[Brief description of drawings]

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

FIG. 2 is a diagram for explaining a display example and a method of creating image data on the display device for route guidance display of the above.

FIG. 3 is a diagram illustrating data stored in an image data ROM of the above.

FIG. 4 is a diagram illustrating writing of data in a V-RAM of the image controller of the above.

FIG. 5 is a diagram illustrating a display example of a conventional example and a method of creating image data.

FIG. 6 is a diagram illustrating another display example of the conventional example and a method of creating image data.

[Explanation of symbols]

 11 image data ROM (image data storage means) 12 image controller (image writing control means) 15 display device (display means) for route guidance display A arrow (image) A1 to A5 blocks

Claims (2)

[Claims] 1. An image data storage means for holding image data relating to an image to be displayed, and screen information that can be immediately displayed by inputting the image data from the image data storage means is temporarily stored and held as a frame buffer and the image is displayed. Image writing control means for outputting as information and display means for displaying the image by inputting the image information from the image writing control means are provided, and the image data storage means includes data of the image itself. An image display device, which holds the image data divided into a plurality of blocks. 2. The image according to claim 1, wherein the image data storage means holds the image data divided into a plurality of blocks having a minimum size including the data of the image itself. Display device.