JPH04288593A - Image display device - Google Patents

Abstract

PURPOSE:To enable continuous scrolling by dividing an image into proper size and storing it in a 1st storage means, and transferring the image to a 2nd storage means and a 3rd storage means when it needs to be displayed. CONSTITUTION:The large-scale image is divided and stored in the 1st storage means 19 and when the image is displayed, data of the divided images whose size are larger than a display part are copied to the 2nd storage means 21. When the image is scrolled and data in a range to be displayed after the scrolling are present in the 2nd storage means 21, the necessary data are copied from the 2nd storage means 21 to the 3rd storage means 7, and transferred to a display means 3, which displays the scrolled image. When the data in the range to be displayed after the scrolling are not present in the 2nd storage means 21, data of a part which becomes unnecessary are discarded and data in a new necessary range are transferred from the 1st storage means 19 to the 2nd storage means 21; and the data required for the display are copied from the 2nd storage means 21 to the 3rd storage means 7.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] This invention relates to a computer-based image display device, and in particular, it is capable of scroll display (shifting the display position of an image on the screen and displaying an image that was previously not displayed). The present invention relates to an imaging device.

0002

2. Description of the Related Art FIG. 8 is an overall configuration diagram of a conventional image display device disclosed in, for example, Japanese Unexamined Patent Publication No. 62-98389. In the figure, 1 is an input circuit that controls the input of image data G, and the image data G is input to the CPU 2. CPU2
The data processing means 2A performs data processing on the image data G and outputs the result as display data H, and the display means 2A extracts address information from the image data G and displays the image on the display screen of the CRT 3, for example. It is equipped with address calculation means 2B that outputs address data A for position determination, and VRAM write area determination means 2C. The calculation results of CPU2 are stored in WORK RAM.
4, and also includes an address data ROM5.

Display data H and address data A displayed by the CPU 2 are input to the VDP 6. The VDP 6 includes a writing unit 6A that writes the display data H into the VRAM 7 and the image data G based on the VRAM writing area determining unit 2C, and a reading unit 6B that executes a display function of reading display data stored in the VRAM 7 and displaying it on the CRT 3. and. 8 indicates a storage means provided in the VRAM 7.

The processing method of this storage means 8 will be explained using FIG. This figure shows the position of image data viewed on the display screen of the CRT 3, and is divided into areas 9 to 17. 9 is an area that is actually displayed, and 10 to 17 are areas that are not displayed. The conventional image display device configured as described above was capable of scrolling image data existing in the storage means at high speed.

[0005]

[Problems to be Solved by the Invention] However, in the image device configured as described above, for example, the image is
In the case of a large scale such as 10,000 x 10,000 pixels with 8 bits per pixel, the amount of data is 100 megabytes, and in order to store all this data in the second storage means, a storage area of more than 100 megabytes is required. It has been difficult to scroll large-scale images at high speed.

The present invention has been made to solve the above problems, and it is possible to scroll and display large-scale images at high speed, and to display not only images but also large-scale figures such as points, line segments, and areas. By managing data in a unified manner at the same time, the aim is to perform high-speed scrolling when displaying them in an overlapping manner.

[0007]

[Means for Solving the Problems] An image display device according to the present invention includes display means for displaying image data and a scrolling function for moving displayed content in any direction such as up, down, left, or right on the display screen. , a first storage means for storing divided image data, a second storage means for storing data in a larger range than the portion displayed on the display means among the data in the first storage means, and a first storage means. The divided image management means detects data to be stored in the second storage means out of the data therein and copies it to the first storage means, and the third storage means stores display contents.

[0008] Furthermore, the above-mentioned image display device has a graphic that integrates a divided image management means using a tree structure for recursively dividing and managing space and a division management means for managing line segment data using the same tree structure. It is equipped with management means.

[Operation] In the image display device configured as described above, a large-scale image is divided in advance and stored in the first storage means, and when displaying the image, one portion of the display portion of the divided image is divided. Copy large data to the second storage means. When scrolling, if data in the range to be displayed after scrolling exists in the second storage means, the necessary data is copied from the second storage means to the third storage means and transferred to the display means. indicate. When the data in the range to be displayed after scrolling does not exist in the second memory,
After discarding the unnecessary part of the data in the second storage means and transferring the newly necessary range of data from the first storage means to the second storage means, the data necessary for display is transferred to the second storage means. The information is copied from the means to the third storage means and transferred to the display means.

Furthermore, in order to speed up the display, display content management means is provided, which specifies data that does not exist in the third storage means among the data to be displayed after scrolling, and transfers such data from the second storage means to the third storage means. Copy to storage means. Then, the data in the third storage means is transferred and displayed on the display means.

[0010] Furthermore, the above-mentioned image display device manages graphical data such as points, line segments, and regions stored in the first storage means in advance using a tree structure or the like, and operates the graphical management means. The divided image management means discovers the necessary image data as described above and copies the display data to the third storage means, and furthermore, the division management means copies the graphic data necessary for display to the third storage means. Since the data in the third storage means is transferred to the display means, the graphic data is scrolled and displayed at the same time.

[0011]

[Example] Example 1. One embodiment of this invention will be described based on FIG. 1. FIG. 1 is a block diagram showing one embodiment of the present invention. Image data G is input by an input circuit 1. The input image data G is processed by a divided image management means, for example, an image dividing device 18, and is stored in a first storage means, for example, a hard disk 19. When displaying an image, a divided image management means, such as a divided image management device 20, operates, and this divided image management device 20 stores image data unnecessary for display on a second storage means, for example, a logical screen 21. is discarded, and only the image data necessary for display is sent to the logical screen 2 through the writing device 22.
1 is stored. Then, the display content management means, such as a VRAM writing device 23, stores the portion of the data in this logical screen 21 to be displayed in a third storage means, such as a
Copy to RAM7. The data in the VRAM 7 passes through the output circuit 24 and is displayed on a display means such as a CRT 3. At this time, the image dividing device 18 and the divided image managing device 20 exchange information with the CPU 2 to proceed with the process. Here, the image dividing device 18,
The divided image management device 20, VRAM writing device 23, logical screen 21, and VRAM 7 exist in the main memory 25. By providing the display content management means in this manner, the amount of image data to be transferred from the second storage means to the third storage means is reduced, the time required for display is shortened, and scrolling display is also made faster.

Next, the processing of the image dividing device 18 will be explained. When the image data G is input to the image dividing device 18, the image is developed and divided into appropriate sizes, for example, 512×512 pixels in this embodiment. These divided images are each downloaded to a file on the hard disk 19 in an appropriate format such as run length or bit image. When downloading to a file, a file for image data management is also created on the hard disk 19. This file contains the file name, seek address, top left coordinates of the image,
This is a table that describes management information such as the coordinates of the lower right corner.

The processing of the divided image management device 20 will be explained based on FIG. 2. First, initial input for reading a file for image data management (step 26) is performed. After the initial input, the system waits for an input until a command to scroll is input (step 27). When a command to scroll is entered, it is checked whether the entire range to be displayed after the scroll is executed is present in the logical screen 21 (step 28). If all the data exists in the logical screen 21, the process returns to step 27 without doing anything. Furthermore, if the display position after scrolling protrudes from the logical screen 21, unnecessary parts are discarded (step 29).
. After that, after searching for the necessary part (step 30), the part necessary for display is transferred from the hard disk 19 to the logical screen 21 through the writing device 22 (step 31).
After doing so, the process returns to step 27.

The unnecessary and necessary parts for the above-mentioned display will now be explained based on FIG. 3. It is assumed that the 3×3 rectangle on the left side of this figure is the data in the current logical screen 21, and the shaded A in the figure is data stored in the VRAM 7, that is, data displayed on the CRT 3. The size of this logical screen 21 is set to be one size larger than the size of data stored in the VRAM 7. Since the image data is divided into 512 x 512 pixels as described above, the logical screen 21 has 1536 x 1536 pixels. When the display portion moves in the direction of the arrow in the figure by scrolling, the display portion A protrudes from the logical screen 21. Therefore, we discarded parts that were not needed for the time being, and
The part to be displayed is brought to the logic screen 21. The shaded part B in the diagram is considered not to be necessary for display for the time being.
This shaded part B is called an unnecessary part. On the other hand, the diagonally lined portion C in the figure is necessary for display, and the diagonally shaded portion C in this figure is called a necessary portion. And V.R.A.
The M writing device 23 is activated after a scroll command occurs and the operation of the divided image management device 20 is completed, and writes the VRAM.
The writing device 23 calculates the portion necessary for display on the logical screen 21 and copies the data to the VRAM 7.

Example 2. A second embodiment of the invention will be described below. The configuration is similar to that of the first embodiment, but the difference is that a tree structure is used for processing by the divided image management device 20. Further, among the processes of the divided image management device 20, the processes of initial input (step 26) and search for necessary portions (step 30) are different from the first embodiment, and these processes will be explained based on FIG. 4. For example, 4
The case of management using branch trees will be explained. The space in which the image data G exists is considered to be the entire space. The entire space is recursively divided into four parts, and the divided images in the space corresponding to each node of the tree are stored in that node. For example, G1 in FIG. 4(a) occupies one-fourth of the total space, so it is stored in the node corresponding to the child of the root as shown in FIG. 4(c). On the other hand, Figure 4
F1 in (b) occupies another quarter of the space corresponding to G1, so F1 is added to the child node of the node that stores G1.
Remember 1. When the divided images in FIGS. 4(a) and 4(b) are put into a tree structure in this way, a tree structure as shown in FIG. 4(c) is created. Initial input (step 26) is performed in this manner. On the other hand, when searching for a necessary part, consider a rectangle of the necessary part. Starting from the roots of the tree, trace the nodes that manage the spaces that overlap this rectangle. As you trace the children, you can find nodes that match the display magnification. List all divided images stored in such a node. Search for the required part (
Step 30) is performed in the manner described above. This results in
This has the effect of speeding up the search for divided images to be displayed, shortening the time required for display, and speeding up scrolling.

[0016] In the second embodiment, a quadrilateral tree with equal area division was used, but other tree structures such as k-d tree, BD tree, etc.
Processing may be performed using a tree structure such as an MD tree, and similar effects can be achieved.

Example 3. A third embodiment of the invention will be described below. The configuration is the same as in Example 1, but V
The difference is in the processing of the RAM writing device 23. The processing of this VRAM writing device 23 will be explained based on FIG. 5. Let rectangle A in FIG. 5 represent data currently in the VRAM 7. Assume that a scroll command causes the contents of the VRAM 7 to be moved in the direction of the arrow to the position of rectangle B in FIG. At this time, the overlapped part of A and B is VRAM7
The data of the part that remains in the VRAM 7 and is included in A but not included in B is discarded from the VRAM 7, and the data of the part that is not included in A but included in B is copied from the logical screen 21 to the VRAM 7. The above is the processing of the VRAM writing device 23. This has the effect of reducing the amount of data transferred from the logical screen 21 to the VRAM 7 and increasing the scrolling speed.

Example 4. Regarding an image display device that displays line segment data at the same time as an image according to a fourth embodiment of the present invention,
This will be explained based on FIG. 1 to 25 in the figure are the same as in the second embodiment. However, the divided image management device 20 is placed in a figure management device 32, which is a figure management means, for example, and the figure management device 32 has the divided image management device 20 and a line segment division management device 33, which is a division management means, as components. have as. The line segment data v is sent to the hard disk 19 via the input circuit 34.
stored above. Then, initial input is performed in advance using the line segment division management device 33. In response to a display command such as a scroll command, the figure management device 32 operates, image data is displayed on the logical screen 21, and line segment data is displayed on the V
Both are transferred to the RAM 7 via the writing device 22.

Next, the processing of the graphic management device 32 will be explained in detail. The figure management device 32 performs initial input of divided images and line segment data in advance using the divided image management device 20 and line segment division management device 33, respectively. The divided image management device 20 and the line segment division management device 33 are activated by the display command. Here, the initial input processing will be explained based on FIG. 7. It is assumed that FIGS. 7A and 7B represent divided images and line segment data existing in the management space, respectively. Similarly to the second embodiment, the divided image management device 20 stores divided images in nodes of a tree structure. The line segment division management device 33 recursively divides the space so that the number of data corresponding to the space of one node is less than a certain capacity, for example, two lines or less, and stores the data in the nodes whose capacity is less than the certain capacity. do. For example, there are three line segments in the upper right space that divides the entire space into quarters in Figure 7(b), so this space is further divided into four, and each line segment is divided into four parts. stored in the corresponding section. For example, in Figure 7 (
A line segment existing across the space of two nodes, such as line segment v2 in b), is stored in each corresponding node. In this way, when the data shown in FIGS. 7(a) and 7(b) exist in the entire space, a tree structure as shown in FIG. 7(c) appears. Initial input to the graphic management device 32 is performed in this manner. On the other hand, if a request for display occurs, the above-mentioned Example 2
Similarly, the search range is first determined, and by tracing the tree, the divided images and line segment data necessary for display are discovered. The above is the process of searching for necessary parts by the graphic management device 32. This allows not only images but also line segment data to be scrolled at high speed.

Furthermore, in the fourth embodiment, line segments are scrolled simultaneously with images, but only images may be displayed during scrolling, and line segments may be searched and displayed after scrolling has stopped; Scrolling becomes faster because less processing is required to scroll.

Furthermore, although only images and line segments were displayed in the fourth embodiment, it is also possible to store various figures such as points, areas, symbols, etc. in a tree structure using a similar method and display them scrolling. The same effect as in the fourth embodiment can be obtained.

[0022]

Effects of the Invention As described above, the present invention divides an image into appropriate sizes and stores them in the first storage means, and transfers them to the second storage means and third storage means as required for display. By doing this, when scrolling large images, the second
Even when the storage means cannot be large enough, scrolling can be performed continuously.

Furthermore, in the image display device of the second invention, by providing the figure management means that integrates the divided image management device and the division management means, not only image data but also other data can be superimposed at high speed. A scrollable display is possible.

[Brief explanation of the drawing]

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

FIG. 2 is a diagram illustrating processing of the divided image management device according to the first embodiment of the present invention.

FIG. 3 is a diagram for explaining data written to a logical screen and data discarded from the logical screen during processing by the divided image management device according to the first embodiment of the present invention.

FIG. 4 is a diagram for explaining the processing of the divided image management device according to the second embodiment of the present invention.

FIG. 5 is an explanatory diagram of processing of a VRAM writing device according to a third embodiment of the present invention.

FIG. 6 is a block diagram showing a fourth embodiment of the invention.

FIG. 7 is a diagram for explaining the processing of the graphic management device according to the fourth embodiment of the present invention.

FIG. 8 is a block diagram showing a conventional image display device.

FIG. 9 is a diagram illustrating a processing method of a storage means of a conventional image display device.

[Explanation of symbols]

3 Display means 7 Third storage means 8. Memory means 9 Display area 19 First storage means 20 Divided image management means 21 Second storage means 32 Graphic management means 33. Division management means

Claims (2)

[Claims] Claim 1: An image display device comprising display means for displaying image data and a scrolling function for moving displayed content in any direction such as up, down, left, or right on the display screen, in which divided image data is stored. first storage means;
a second storage means for storing data in a larger range than the part displayed on the display means out of the data in the first storage means; An image display device comprising a divided image management means for discovering data to be displayed and copying it to the first storage means, and a third storage means for storing display contents. 2. The image display device according to claim 1, wherein divided image management means uses a tree structure for recursively dividing and managing space, and line segment data is managed using the same tree structure. Equipped with figure management means that integrates division management means,
An image display device that displays line segment data superimposed on an image.