JP3093228B2 - Image processing apparatus and method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus capable of performing a restoration process and a method thereof.

[Related Art] In an image processing apparatus having data in a bit map format, a restoration process (UNDO) for canceling the latest input data and returning to the previous state is indeterminate. is there. In order to realize such processing, in the conventional technology, a double drawing buffer for holding data in a bit map format is prepared, data before input is saved in one buffer, and character input is performed. Draw the subsequent data in the other buffer and display it, and if UNDO is done, switch the buffer of interest to the previous buffer or replace the data of the bit map It was realized by.

[Problems to be Solved by the Invention] However, in the above-mentioned conventional technology, a large number of memories are required and a compact system is configured because buffers for holding bit map data must be prepared in duplicate. It was difficult.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a position information storage unit capable of storing a plurality of pieces of position information for displaying a graphic in an input order, Display means for displaying a figure based on the stored position information; one image storage means for storing the position information as image data; and storing new position information when new position information is input. Storage control means for storing the position information previously input among the position information stored in the position information storage means as image data in the image storage means; Means for instructing invalidation of the display of the image, and when the instruction means instructs invalidation of the display for the latest input, the image of the figure stored in the image storage means is invalidated. Display control means for controlling the display means so as to display image data.

Further, the present invention stores a plurality of pieces of position information for displaying a figure in a position information storage means in the order of input, displays a figure based on the position information stored in the position information storage means, and displays new position information. Is input, the position information is stored in the position information storage means, and the position information previously input among the position information stored in the position information storage means is stored as one image data as image data. Means for controlling the display means to store the image data of the figure stored in the image storage means when invalidation of the display for the latest input is instructed. Provide a way.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing a basic configuration of the present invention. 1
Is an input device, and accepts drawing instructions such as input of an image and designation of an input position from a user, and various instructions such as UNDO described later. Reference numeral 2 denotes a command analysis device which determines whether the input from the input device 1 is a command for UNDO or a drawing instruction, corrects the command to a command suitable for the system, and outputs the command to the command management device 3.

When the input command is related to a drawing instruction, the command management device 3 stores the command in the table 11 or
The data is held in the vacant ones and output to the display controller 4 for displaying the data corresponding to the command. At this time, if there is a table in which the data is stored, the command management device 3 fetches the command of the table after outputting to the display control device 4 and sends it to the drawing device 7. If the input command is an UNDO instruction, the display control device 4 is instructed to display the data in the drawing buffer 8 to perform the UNDO.

The drawing device 7 transfers the data in the bit map format to the drawing buffer 8 via the command expanding device 6.

The display control device 4 adds a parameter for display to the command if necessary, and displays the data on the display device 5 as bit map data via the command expanding device 6. In addition, the data of the drawing buffer 8 is displayed according to a command from the command management device 3.

FIG. 2 is a diagram showing a specific configuration example of an image processing apparatus according to one embodiment of the present invention.

Here, the CPU is a microprocessor, which performs operations and logical judgments for various processes and performs address bus A
B, control components connected to these buses via the control bus CB and the data bus DB.

The address bus AB transfers an address signal specifying each component to be controlled by the microprocessor CPU, and the control bus CB transfers and supplies a control signal to each component to be controlled by the microprocessor CPU. I do. The data bus DB transfers and transfers data between the constituent devices.

The ROM is a read-only fixed memory, and a microprocessor CPU described later with reference to the flowchart of FIG.
The procedure of various processes, such as the control procedure of, is stored.

The RAM is a writable random access memory, and is used to temporarily store various data from each component. In particular, the drawing buffer 8 and the table 11,
There are also areas corresponding to 12.

CRT is a display unit for screen display.
It has a VRAM for storing as an image, so that it is displayed on the screen.

The PD is a pointing device that is used to select the type of image to be input, to specify an input position, and to issue an instruction such as UNDO.

FIG. 3 is a flowchart of the processing operation of this embodiment, and FIG. 4 is a specific display example of a CRT at the time of UNDO processing in this embodiment. The operation of this embodiment will be described with reference to the example of FIG. 4 based on the flowchart of FIG.

Here, FIG. 4 shows a straight line (straight line A ₁₎ connecting A ₁ and A _{2 first.}
A ₂₎ to draw a (FIG. 4 <a>), then B _1, B ₂ by drawing a straight line (straight line B ₁ B ₂₎ connecting (Figure 4 <b>), then draw the straight line B Undo processing was performed on ₁ B ₂ (Fig. 4 <c>)
This shows how the display of the CRT changes at the time.

Also, it is assumed that the straight line data is registered in the table in a format as shown in FIG. That is, in the table, the two-dimensional coordinates of the start point and the end point corresponding to the position specified by the input on the CRT are registered as a pair. Note that, here, only two tables, 11 and 12, will be described, and only tables corresponding to one straight line (line segment) will be described.

Also, the VRAM and the drawing buffer are configured to be coordinated in bit units as shown in FIG.
The format of the RAM and the drawing buffer is the same except for the address.

Now, a specific operation will be described. In the flowchart of FIG. 3, first, in step S1, parameters, tables, and buffers necessary for the present process are initialized.
Next, in the input process of step S2, the process waits until an image input or an UNDO process is instructed by the user. Note that details such as a method of inputting a straight line are omitted because they are conventional techniques.

Here, it is assumed that the straight line A ₁ A ₂ is input _first . Then, in the determination processing of whether or not the instruction is the UNDO of step S3,
Since the image input has been made, the process proceeds to step S4 assuming that the instruction is not an UNDO instruction. In step S4, the input straight line data is registered in the empty table. Since both tables 11 and 12 are empty tables now, the position coordinates of the start point and the end point are registered in the table 11. In the present embodiment the position coordinates of A ₁ and A ₂ are registered.

Next, in step S5, the data is developed on the VRAM using the data of the table 11 just registered and displayed. Thus, as shown in FIG. 4 <a>, the first straight line A ₁ A ₂
Displayed above, it appears to the user as if a conventional image input was performed. However, as can be seen from the above description, writing has not yet been performed on the drawing buffer 8.

Next, in step S6, it is checked whether or not the previous character input is registered in the table. Since this is the first input, processing is performed assuming that there is no previous image input. When the above process ends, the process returns to the process of step S2. Here, as in the first explanation,
Wait for instructions.

It is assumed that a straight line B ₁ B ₂ shown in FIG. 4 <b> has been input as the next input. Then, UNDO is checked in step S3, and in this case, the process proceeds to step S4. Step S4
Then, the empty table is table 12, so this table
The position coordinates of B ₁ and B ₂ are recorded. In step S5,
Drawing is performed on the VRAM using the data in the table 12. In the next step S6, since the values of the position coordinates of the start point and the end point are registered in the table 11 in the previous image input, the process proceeds to step S7. In step S7, the table used for the previous drawing, that is, table 11 in this example is selected, and drawing is performed in the drawing buffer in step S7.

By the processing so far, the straight line A ₁ A ₂ has been recorded as a bit image in the VRAM and the drawing buffer. On the other hand, the straight line B ₁ B ₂ is only drawn on the VRAM.

Next, the process returns to step S2 and waits for an input again. Here UN
DO shall be instructed. Then, it is determined that an UNDO instruction has been made in step S3, and the process proceeds to step S8. In step S8, the table used immediately before is cleared. In this embodiment, the table 2 in which the straight lines B ₁ B ₂ are registered is cleared. Next, in step S9, the data in the drawing buffer 8 is transferred to the VRAM and displayed. By this processing, the straight line B ₁ B ₂ which is the immediately preceding drawing is undone for the user, and the object of the present invention is achieved.

[Other Embodiments] In the above embodiment, the table for storing image data is 2
Although there is only one, the number can be further increased to increase the number of drawings that can be undone.

Further, in the above embodiment, the table for storing the image data records only the start point and the end point of the straight line. However, the table stores the identifier indicating the type of the image and the parameters required for drawing in each type. (For example, coordinates of two points on the diagonal of a rectangle, coordinates and a radius of a center of a circle, etc.), UNDO can be performed on images of various shapes.

It is also possible to add a parameter such as a line type or a thickness and register the parameter.

In the above embodiment, the input / instruction is performed by the pointing device, but may be another device such as a keyboard.

Further, in the above embodiment, the VRAM and the drawing buffer have the same configuration, but it is also possible to add luminance information, color information, etc. to one or both of them without impairing the spirit of the present invention.

[Effects of the Invention] As described above in detail, according to the present invention, a plurality of pieces of information for displaying a graphic are stored in the order of input as position information, thereby displaying the graphic in a compact device with a reduced memory capacity. It is possible to realize the restoration processing in.

[Brief description of the drawings]

FIG. 1 is a basic configuration diagram of a first embodiment of the present invention, FIG. 2 is a block diagram of an image processing device of the first embodiment of the present invention, FIG. 3 is a flowchart of a display process, and FIG. FIG. 5 is a diagram showing a display example of an image, FIG. 5 is a diagram showing an example of a table of character data, and FIG. 6 is a diagram showing a configuration example of a drawing buffer and a VRAM according to the present invention. DESCRIPTION OF SYMBOLS 1 ... Input device 2 ... Command analysis device 3 ... Command management device 4 ... Display control device 5 ... Display device 6 ... Command expansion device 7 ... Drawing device 8 ... Drawing buffer 11, 12 ... Table CPU: Microprocessor AB: Address bus CB: Control bus DB: Data bus ROM: Fixed memory RAM: Random access memory CRT: Display unit PD: Pointing device

Claims (4)

(57) [Claims] 1. A position information storage means capable of storing a plurality of pieces of position information for displaying a figure in an input order; a display means for displaying a figure based on the position information stored in the position information storage means; One image storage unit for storing information as image data; and when new position information is input, the position information is stored in the position information storage unit, and the position information stored in the position information storage unit. Storage control means for controlling to store the position information previously inputted in the image storage means as image data, instruction means for instructing display invalidation for the latest input, and the latest input by the instruction means A display control unit that controls the display unit to display image data of a figure stored in the image storage unit when an instruction to invalidate the display is given. The image processing apparatus characterized by comprising a means. 2. The storage control unit according to claim 1, wherein when the instruction unit instructs invalidation of the display for the latest input, the storage unit deletes the position information for the latest input stored in the position information storage unit. The image processing apparatus according to claim 1, wherein 3. A plurality of position information for displaying a figure are stored in a position information storage means in the order of input, and a figure is displayed based on the position information stored in the position information storage means. When the position information is input, the position information is stored in the position information storage means, and the position information previously input among the position information stored in the position information storage means is stored as one image storage means as image data. And controlling the display means to display the image data of the graphic stored in the image storage means when the display of the latest input is invalidated. . 4. The apparatus according to claim 3, wherein when the invalidation of the display for the latest input is instructed, the position information corresponding to the latest input stored in said position information storage means is deleted. The image processing method according to the item.