JPH0421154Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field This invention is based on the chain code signal.
The present invention relates to an improvement in an image display device that displays symbols on a display section, and particularly to a magnification setting device for an image display device that can facilitate conversion of the magnification of figures and symbols by converting a chain code signal into a coordinate data signal.

BACKGROUND TECHNOLOGY In recent years, the development of image display devices that display various information using display screens such as CRTs has progressed rapidly. , technology for displaying road map information, etc. is being developed.

The technique disclosed in Japanese Utility Model Application Publication No. 59-98489 is an example of this. Conventional technology displays a road map and information on facilities on the map on a CRT display device, and draws marks on the screen that indicate the road network and facilities such as golf courses and gas stations on the road map. In this case, the above-mentioned image is generally drawn by setting one dot for each step in the direction indicated by a chain code signal from an image data transmission source or the like.

FIGS. 9 to 11 show examples of drawing based on the chain code signal in the prior art.

In FIG. 9, the symbol SP indicates the coordinate position of the drawing starting point, and the numbers 4, 5, . . . , 7, 0, . . . are chain codes indicating the drawing progress direction. Here, the chain codes 4, 5, 7, 0, etc. are predefined to advance in the directions shown in FIG. The number 7 means one step to the bottom left, and the number 0 means one step to the left.

That is, if drawing is performed according to the chain code shown in FIG. 9, a diagram as shown in FIG. 11 will be drawn.

Note that the arrows in FIG. 11 indicate the direction in which one dot is set for each step, and the portions a ₁ , a ₂ , a ₃ . . . indicate each dot.

Problems to be Solved by the Invention According to the above-mentioned conventional technology, the scale of the line diagram drawn according to a series of chain codes is one type, and in order to enlarge or reduce the size of the image, a different scale is required. It is necessary to generate and draw a chain code. In other words, if you want to change the scale arbitrarily, you need to prepare an arbitrary number of chain codes.

In other words, it is necessary to increase the capacity of the storage means for storing the chain code of the image data transmission source that generates the chain code signal, which is an obstacle to miniaturization and cost reduction of the device. .

Furthermore, the chain code signal itself from the image data transmission source is just a code signal, and the code signal itself cannot be processed by adding, subtracting, multiplying, or dividing, and the chain code signal cannot be processed by circuitry or hardware. Therefore, it was impossible to use it in a wide variety of ways.

Means for Solving the Problems The present invention was made in response to the above-mentioned problems, and converts the chain code signal into a coordinate data signal and sets the magnification of the figure/symbol. It is an object of the present invention to provide a technique that can set an arbitrary magnification without increasing the capacity of a signal storage means, and can perform arithmetic processing for setting the magnification using hardware.

In order to achieve this purpose, in an image display device that displays figures and symbols on a display unit based on a chain code signal from an image data transmission source, the chain code is There is provided a magnification setting device for an image display device, characterized in that a signal conversion means for converting a signal into a coordinate data signal is interposed between the image data transmission source and the display section.

Function The present invention operates as follows due to the above-mentioned configuration.

That is, a chain code signal for drawing a figure/symbol transmitted from an image data transmission source is input to a signal converting means, and the signal converting means converts the chain code signal into a coordinate data signal and transmits it to a subsequent stage according to the drawing magnification. Output. Thus, the display section draws figures and symbols at respective magnifications based on the coordinate data signals inputted via the signal conversion means.

Embodiment Referring to FIGS. 1 to 8, a preferred embodiment of the present invention in which the present invention is applied to an automobile navigator device will be described.

First, in FIG. 1, 1 is an image data transmission source,
2 is a conversion section, 3 is a conversion data generation section, 4 is a magnification instruction section, 5 is a control section, and 6 is a display section. Here, the conversion section 2, the conversion data generation section 3,
The magnification instruction section 4 and the control section 5 constitute a signal conversion means.

To be more specific, the image data transmission source 1 transmits a chain code signal for drawing a map to a subsequent stage based on map data read from a storage means such as a compact disk in response to input from a key switch, direction sensor, etc. (not shown). It is a means of outputting.

Further, the converting section 2 is a means for converting the chain code signal from the image data transmission source 1 into a coordinate data signal based on the input from the converted data generating section 3 and the magnification instruction section 4.

The conversion data generating section 3 is a means for outputting coordinate data of a section C corresponding to a chain code as shown at section b in FIG. 2 to the conversion section 2.

In addition, the symbol dx shown in part C in Fig. 2,
dy indicates the amount by which a dot drawn on the screen is moved on the coordinate system when the display screen of the display unit 6 is a two-dimensional coordinate system. For example, as shown in Figure 2, the amount of movement of the dot corresponding to chain code 0 is dx = -1, dy = 0, indicating that it moves one dot to the left on the x-axis, and similarly dx is positive (+ ) moves to the right, minus (-)
If dy is positive (+), it will be moved up; if dy is negative (-), it will be moved down.

Further, the magnification instruction section 4 is a means for inputting a coefficient k for calculating the coordinate data to the conversion section 2 by inputting from a switch or an external device (not shown). For example, when the coefficient k output from the magnification indicator 4 is "2", the coordinate data corresponding to chain code 0 shown in part b of Fig. 2 is as shown in Fig. 5.
When dx=-2, dy=0 and the coefficient k is "3", although not shown, calculations are made as dx=-3, dy=0 in the same way as described above.

The control section 5 is composed of a CRT controller (not shown), etc., and is a means for moving dots on the screen of the display section 6 based on the coordinate data input from the conversion section 2 to draw a map or the like.

Further, the display unit 6 is composed of a CRT or the like, and is disposed at a predetermined location such as an instrument panel in an automobile.

Next, the operation of the preferred embodiment of the present invention having the above configuration will be explained based on the flowcharts shown in FIGS. 3 and 4.

Step 101: A chain code signal is read from the image data transmission source 1 into the converter 2. Assume now that the chain code signal shown in FIG. 2 has been read.

Step 102...The coordinate data corresponding to the chain code signal is read from the conversion data generator 3 and converted.

Step 103... The coordinate data is multiplied by the coefficient k read from the magnification instruction section 4 to obtain new coordinate data.

The coordinate data shown in FIG. 5 is based on the coefficient k=2
The chain code signal shown in FIG. 9 is converted into coordinate data. Note that the symbol "SP" in FIGS. 9 and 5 indicates the starting point of drawing.

Step 104: Add the coordinate data (dx, dy) to the line drawing start point (xs, ys) to calculate the line drawing end point (xE, yE).

Step 105: In step 201 of the line drawing routine shown in FIG. 4, a dot is moved on a straight line from the starting point (xs, ys) to the ending point (xE, yE) to draw a line.

For example, from the "SP" point shown in part d ₁ of Figure 5, d ₂
When the dot is moved according to the coordinate data dx=+2, dy=0 shown in the part, e ₁ to e ₂ shown in FIG.
The line is drawn from part e2 to part e3 in Figure 6 using the coordinate data shown in part _d3 in Figure 5, and the line is drawn in the same way from part _e2 to part _e3 in Figure 5. Line drawing is repeatedly executed up to the en section in FIG. 6, which corresponds to the coordinate data shown in the dn section of , and as a result, as shown in FIG. will be drawn on the screen of the display section 6.

Note that the above-described line drawing is repeated from step 102 to step 102, including the steps described later.
This is done by executing a loop consisting of 108 steps.

Step 106...The end point (xE, yE) obtained in step 104 is rewritten as the start point (xs, ys).

Step 107: Read the next chain code signal from the image data transmission source 1 into the converter 2.

Step 108...Determine whether all chain code signals have been read. If YES, proceed to the next step; if NO, return to step 102.

As described above, by converting the chain code signal into a coordinate data signal, for example, the map shown in FIG. 7 can be enlarged and displayed as the map shown in FIG. 8.

According to the preferred embodiment of the present invention described above, the coordinate data from the conversion data generating section 3 is a basic value, and the drawing magnification can be determined by multiplying it by the coefficient given by the magnification instruction section. However, the coordinate data itself may be set in various ways depending on the magnification.

Effects of the Invention The present invention achieves the following effects due to the above-mentioned structural action.

That is, by converting the chain code signal into a coordinate data signal, the coordinate data can be freely multiplied by a coefficient corresponding to the drawing magnification, and the magnification can be arbitrarily changed. Furthermore, it is not necessary to store each chain code signal corresponding to the type of drawing magnification, and the capacity of the storage means can be reduced, contributing to miniaturization and cost reduction of the apparatus.

Further, the coordinate data signal can be subjected to arithmetic processing, and therefore, the coordinate data can be processed by hardware, so that a wide variety of uses can be expected.

[Brief explanation of the drawing]

FIG. 1 is an electrical block diagram showing a preferred embodiment of the present invention. FIG. 2 is an explanatory diagram showing data output from the conversion data generation section shown in FIG. 1. FIG. 3 is a flowchart of a preferred embodiment of the present invention. FIG. 4 is a flowchart showing a subroutine for executing step 105 of the flowchart shown in FIG. FIG. 5 is an explanatory diagram showing coordinate data obtained by the converter shown in FIG. 1. FIG. 6 is an explanatory diagram showing an image drawn based on the coordinate data shown in FIG. 5.
FIG. 7 is an explanatory diagram showing a map drawn according to a preferred embodiment of the present invention. FIG. 8 is an explanatory diagram showing an enlarged display of the map shown in FIG. 7 according to a preferred embodiment of the present invention. FIG. 9 is an explanatory diagram showing a chain code signal in the prior art. FIG. 10 is an explanatory diagram showing the direction in which dots are advanced based on the chain code signal shown in FIG. 9. FIG. 11 is an explanatory diagram showing an image drawn based on the chain code signal shown in FIG. 9. 1... Image data transmission source, 2... Conversion unit, 3...
...Conversion data generation section, 4...Magnification instruction section, 5...
Control unit, 6...Display unit.

Claims (1)

[Scope of utility model registration request] In an image display device that displays figures and symbols on a display unit based on a chain code signal from an image data transmission source, a signal that converts the chain code signal into a coordinate data signal according to a set drawing magnification of the figure and symbol. A magnification setting device for an image display device, characterized in that a conversion means is interposed between the image data transmission source and the display section.