JP2668464B2 - Cursor display control method in image synthesizer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cursor display control method in an image synthesizing apparatus for synthesizing an image from a main unit and its own image and displaying the image on a display screen.

[0002]

2. Description of the Related Art An image synthesizing apparatus for realizing simultaneous display of different images by synthesizing an image signal from a main body with an image signal of another screen is known. In this type of image synthesizing apparatus, an image from the main body and an image from another screen are synthesized by performing analog addition of two image signals. Also, in order to realize a multi-window, a mask memory having a mask bit corresponding to a pixel unit is provided, and by changing the contents of the mask memory, exclusive display at the time of window superimposition is realized. There is.

However, in the above-described image synthesizing apparatus, since the character cursor and the mouse cursor can be superimposed on the synthetic screen regardless of the multi-window, the superimposed portion of the cursor becomes mixed color, making it difficult to see. There was a problem that it would end up. In order to solve this problem, an apparatus as shown in FIGS. 6 and 7 has been devised.

FIG. 6 is a diagram showing a conventional example of an image synthesizing apparatus for preventing color mixture at a cursor superimposed portion. In the figure,
Reference numeral 1 denotes a frame memory, 2 denotes a mask memory, 3 denotes a mask circuit, 4 denotes a D / A converter, and 5 denotes an analog OR circuit.

Pixel data forming an image is stored in the frame memory 1. One pixel is composed of a plurality of bits. The mask memory 2 has a plurality of mask bits, and the mask bits of the mask memory 2 and the pixel data of the frame memory 1 have a one-to-one correspondence. A mask bit is a bit in the mask memory.
For example, 1 indicates that there is a mask, and 0 indicates the mass.
Indicates that there is no black. From frame memory 1 to address A _ij
Assuming that the pixel data at the position (corresponding to the positions i and j on the display screen) has been read, the mask bits at the address A _ij are simultaneously read from the mask memory 2.

The pixel data from the frame memory 1, the mask bits from the mask memory 2, and the display presence / absence signal from the main unit are input to the mask circuit 3. The display presence / absence signal from the main body indicates whether or not the pixel data at the address A _ij sent from the main body is blank. If the pixel data is blank, the display presence / absence signal has a value of “0”. If not blank, the display presence / absence signal has a value of "1". The mask circuit 3 outputs a blank signal when one or both of the input mask bit and the display presence / absence signal are “1”, and otherwise outputs the input pixel data as it is. To do.

[0007] Pixel data output from the mask circuit 3 is input to a D / A converter 4. D / A converter 4
Generates and outputs an analog pixel signal based on the value of the input pixel data. The output of the D / A converter 4 is input to the analog OR circuit 5. Analog OR
The analog pixel signal output from the main body side is input to the other input of the circuit 5. The analog OR circuit 5 adds the input signals in an analog manner. In the figure, D
Although only one output from the / A converter 4 is shown, it actually outputs R, G, and B analog signals. The same applies to the analog pixel signal from the main body side. Analog O
There are actually three R circuits 5.

FIG. 7 is a diagram showing another conventional example of an image synthesizing apparatus for preventing color mixture of a cursor superimposed portion. In the figure, reference numeral 6 denotes a display presence / absence detection unit. In addition, the same code | symbol as FIG. 6 shows the same thing. The display presence / absence detecting unit 6 checks whether or not the analog pixel signal indicates a blank based on the level of the analog pixel signal sent from the main body.
If it is blank, it outputs "0", and if it is not blank, it outputs "1". Display presence / absence detection unit 6
Is input to the mask circuit 3. The other configuration is the same as that of the conventional example shown in FIG. 6, and the operation is substantially the same.

[0009]

In the image synthesizing apparatus shown in FIGS. 6 and 7, it is possible to prevent the color mixture at the cursor superimposed portion, but in each case, the hardware needs to be changed, which increases the cost and increases the mounting cost. Has the drawback of being complicated. The present invention has been made in view of this point, and in an image synthesizing apparatus that synthesizes an image on the main body side and an image of the user and displays the image on a display screen, the color mixing of a cursor superimposed portion is performed with a simple configuration. The purpose is to be able to prevent.

[0010]

FIG. 1 is a diagram illustrating the principle of the present invention. As shown in the figure, the cursor display control method in the image synthesizing apparatus of the present invention comprises a frame memory for storing pixel data, and a mask memory having bits corresponding to the pixel data of the frame memory on a one-to-one basis. If the bit read from the mask memory indicates that a mask is present, blank data is output, and if the bit read from the mask memory indicates no mask, the blank data is output. A mask circuit that outputs the output pixel data as it is, a D / A converter that converts the pixel data output from the mask circuit into an analog pixel signal, an output of the D / A converter, and an analog signal transmitted from the main unit. Analog O that adds signals in analog
A cursor display control method in an image synthesizing apparatus comprising an R circuit, and a processing device having a cursor download command processing means and a cursor movement command processing means, wherein the cursor download command processing means transmits a command from a main unit. A cursor download command that is received by the image synthesizing apparatus and is operated so as to hold a cursor pattern added to the cursor down command in a storage unit; The means operates when the image compositing apparatus receives a cursor movement command sent from the main unit, and stores the previous cursor pattern in the mask memory.
Process to delete it, then move the cursor
The cursor display position after movement added to the command
And the window mass stored in the mask memory
Cursor to see the cursor pattern
Configured to perform processing for expansion to disk memory.
It is characterized by having been done.

[0011]

The pixel data at the address A _ij of the frame memory and the bit (referred to as a mask bit) at the address A _ij of the mask memory are simultaneously read. The read pixel data and mask bits are input to the mask circuit. The mask circuit outputs blank data when the input mask bit indicates that there is a mask, and outputs the input pixel data as it is when the input mask bit indicates that there is no mask. To do. The pixel data output from the mask circuit is input to the D / A converter. The D / A converter converts the input pixel data into R, G, B analog pixel signals. The analog pixel signal output from the D / A converter is analog O
It is input to the R circuit, and the analog pixel signal from the main body device is also input to the analog OR circuit. The analog OR circuit adds the input analog signals in an analog manner. The output of the analog OR circuit is sent to a display.

The main unit transfers the cursor download command to the image synthesizing apparatus in advance. A cursor pattern is added to the cursor download command. When the cursor download command is received by the image synthesizer, the cursor download
The command processing means starts operating and writes the transferred cursor pattern into the storage unit.

When changing the display position of the cursor, the main unit transfers a cursor movement command to the image synthesizing apparatus. Cursor display position data after movement is added to the cursor movement command. When the cursor movement command is received by the image composition device, the cursor movement command processing means starts operating. The cursor movement command processing means masks and memoizes the previous cursor pattern.
Process to delete from the
The cursor display position after the move that is added to the move command
Windows stored in memory and mask memory
The cursor pattern that is being held by referencing the mask
Is performed to expand the in the mask memory.

[0014]

FIG. 2 is a block diagram showing one embodiment of the present invention. In the figure, 10 is an image synthesizing device, 11 is a frame memory, 12 is a mask memory, 13 is a mask circuit, 14 is a D / A converter, 15 is an analog OR circuit, 16 is a working RAM, and 17 is a microprocessor. ,
18 is an interface circuit, 19 is a CRT control circuit, 2
0 is a main unit, 21 is a frame memory, 22 is a microprocessor, 23 is an interface circuit, and 24 is a D /
An A converter, 25 is a CRT control circuit, and 30 is a CRT.

A frame bus 11, a mask memory 12, a working RAM 16, and a microprocessor 17 are connected to the common bus. The pixel data read from the frame memory 11 is input to the upper input terminal of the mask circuit 13, and the mask bits read from the mask memory are input to the lower input terminal of the mask circuit 13. The mask circuit 13 outputs blank data (all 0) when the input mask bit is “1”, and outputs the input pixel data as it is when the input mask bit is “0”. . The output of the mask circuit 13 is D
It is input to the / A converter 14. Analog OR circuit 1
5 adds the analog pixel signal from the D / A converter 14 and the analog pixel signal from the main unit 20 in an analog manner. The output of the analog OR circuit 15 is a CRT.
Sent to 30.

The work RAM 16 stores temporarily used data. The microprocessor 17 performs various processes. The interface circuit 18 has a function of transmitting data to the main device 20 and receiving data from the main device 20. CRT control circuit 1
9 generates a horizontal synchronizing signal and a vertical synchronizing signal to be transmitted to the CRT 30 according to the synchronizing signal transmitted from the CRT control circuit 25, and also generates an address to be transmitted to the frame memory 11.

The frame memory 2 is also included in the main unit 20.
There is one. The frame memory 21, the microprocessor 22, and the interface circuit 23 are connected to a common bus. An address from the CRT control circuit 25 is input to the frame memory 21, and pixel data corresponding to this address is read from the frame memory 21. The microprocessor 22 performs various processes. The interface circuit 23 transmits data to the image composition device 10 and receives data from the image composition device 10. The frame memory 2 is used as the D / A converter 24.
Pixel data from 1 is input. D / A converter 2
The output of 4 is input to the analog OR circuit 15. CRT
The horizontal synchronization signal and the vertical synchronization signal generated by the control circuit 25 are sent to the CRT control circuit 19.

FIG. 3 is a diagram for explaining the mask memory. The mask memory has one mask bit corresponding to one pixel of the frame memory. When the value of the mask bit is "1", display of the corresponding pixel of the frame memory is prohibited.

The operation of the embodiment shown in FIG. 2 will be described. The main unit 10 preliminarily converts the cursor pattern into the image synthesizing device 10 via the command / status communication interface.
Download it to. The image synthesizing device 10 uses the downloaded cursor pattern as the work RAM 1
Save to 6. The cursor pattern has a value of "1"
Is composed of bits.

The main unit 20 sends a cursor movement command to the image synthesizing apparatus 10 in accordance with the display movement of the cursor. The cursor movement command has coordinate data indicating the position after movement as a parameter. Image synthesizer 1
0 expands the above-described cursor pattern downloaded in the mask memory 12 in accordance with the coordinates after the movement by the cursor movement command.

FIG. 4 is a diagram showing an example of a processing flow of the image synthesizing apparatus of the present invention. The image synthesizing device 10 performs the following processing. In step S1, it is checked whether a command has been received. In the case of Yes, it progresses to step S2.
If No, it waits until the command is received. In step S2, it is checked whether the received command is a cursor download command. If Yes, the process proceeds to step S6, and if No, the process proceeds to step S3. Step S
At 3, it is checked whether the received command is a cursor movement command. In the case of Yes, it progresses to step S4 and N.
If it is o, the process proceeds to step S5.

In step S4, cursor movement processing is performed. In step S5, other command processing is performed.
In step S6, the cursor pattern sent from the main unit is downloaded into the working RAM. In step S7, a command end status is transmitted.

FIG. 5 is a diagram showing an example of the cursor movement processing flow of the present invention. The following processing is performed in the cursor movement processing. In step M1, it is determined whether a cursor movement command has been received. If Yes, the process proceeds to step M2, and if No, the process proceeds to step M5. In step M2, it is checked whether or not the previous cursor position overlaps the area where the window mask is being performed. If Yes, the process proceeds to step M4, and if No, the process proceeds to step M3. Window mask
It is composed of a bit with a value of "1". At step M3, the cursor pattern developed in the mask memory is cleared. In step M4, the expanded cursor pattern is cleared for the area where the window mask is not set.

At step M5, the cursor position after the movement is stored in the RAM. In step M6, it is checked whether or not the moved cursor position overlaps the area where the window mask is being performed. If yes, step M
8. If No, go to step M7. In step M7, the cursor pattern is developed in the area of the mask memory corresponding to the new coordinate information. In step M8, a cursor pattern is developed in an area where a window mask is not set, corresponding to the new coordinate information.

[0025]

As is apparent from the above description, according to the present invention, it is possible to easily realize exclusive display when the cursor on the main body overlaps on the composite screen without changing the hardware.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of the present invention.

FIG. 2 is a block diagram of one embodiment of the present invention.

FIG. 3 is a diagram illustrating a mask memory.

FIG. 4 is a diagram showing an example of a processing flow of the image synthesizing apparatus of the present invention.

FIG. 5 is a diagram showing an example of a cursor movement processing flow of the present invention.

FIG. 6 is a diagram showing a conventional example of an image synthesizing apparatus.

FIG. 7 is a diagram showing another conventional example of the image synthesizing apparatus.

[Explanation of symbols]

 Reference Signs List 10 image synthesizing device 11 frame memory 12 mask memory 13 mask circuit 14 D / A converter 15 analog OR circuit 16 work RAM 17 microprocessor 18 interface circuit 19 CRT control circuit 20 main unit 21 frame memory 22 microprocessor 23 interface Circuit 24 D / A converter 25 CRT control circuit 30 CRT

Claims (1)

(57) [Claims] A frame memory for storing pixel data, and a bit corresponding to the pixel data of the frame memory on a one-to-one basis.
A mask memory with bets, if if the bits read from the mask memory indicates that there mask outputs blank data, bits read from the mask memory indicates a maskless A mask circuit for directly outputting the pixel data read from the frame memory, a D / A converter for converting the pixel data output from the mask circuit into an analog pixel signal, an output of the D / A converter, and a main unit. A cursor display control method in an image synthesizing apparatus comprising: an analog OR circuit that adds analog signals sent from the processor in an analog manner; and a processing device having cursor download command processing means and cursor movement command processing means. The cursor download command processing means is A cursor download command, which is operated when the image synthesizing apparatus receives the download command, and stores a cursor pattern added to the cursor down command in the storage unit. Operates when the image compositing device receives a cursor movement command sent from the device and masks the previous cursor pattern into a mask memo.
Process to delete from the
The cursor display position after the move that is added to the move command
Windows stored in memory and mask memory
The cursor pattern that is being held by referencing the mask
To expand to the mask memory.
A cursor display control method in an image synthesizing device characterized by being created .