JPS6014356B2 - image display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an image display device, and particularly to a display device that displays large amounts of image data in sections.

In a dot refresh type image display device, before displaying, image data to be displayed is stored in a refresh memory with a capacity corresponding to the number of pixels for one display image screen, and the image data is stored or stored in the fresh memory. By reading out the image data for each refresh cycle,
The image is displayed.

Therefore, conventionally, when displaying a large amount of image data that spans multiple display screens, it is fixedly divided in advance into partial images of a size equivalent to the amount of data that can be stored in the refresh memory, that is, the size of one display screen. Then, each partial image is displayed individually, or the large-capacity image data is coarsely resampled so that it can be stored in a refresh memory, and the fineness of the original large-capacity image is reduced and displayed. Therefore, it has been impossible to display an arbitrary region of a large amount of original image data with arbitrary precision. An image data display device that improves these drawbacks uses an electron tube as the image memory, reads out the display area using a beam addressing method, and can change the display area and accuracy of image data. The drawback is that it has a limited capacity and cannot display large amounts of image data.

In order to eliminate these drawbacks, the present invention provides a plurality of display reference points in large-capacity image data in association with two-dimensional images, thereby creating a data-compressed image corresponding to the image area to be displayed. The purpose is to enable high-speed data reading, and the figures will be explained in detail below.

FIG. 1 shows a block diagram showing the configuration of an embodiment of an image display device of the present invention.

In the figure, 1 is a large capacity image file, 2 is a refresh memory, 3 is a display section, 4 is an operation section, and 5 is a control section. In accordance with instructions input from the operating section 4, the control section 5 reads out required image data from the large-capacity image file and sends it to the refresh memory 2. The display section 3 displays the image data in the refresh memory 2 while refreshing it.
FIG. 2 is an explanatory diagram of the relationship between image data and display reference points, where 6 is image data, 7 is a display reference point, 8 is a data block, 9 is a display image data area, 10-1 is absent, and 1 is a display reference point.
0-4 are the four vertices P, , of the display image data area 9, respectively.
They are P2, P3, and P4.

In this figure, image data is illustrated as two-dimensional array data for convenience of explanation and to facilitate association with images. The display reference point 7 is located at a lattice point when the two-dimensional image is divided into a lattice shape, and the area Z divided by each lattice becomes a data block 8. For the sake of explanation, the display reference point 7 will be referred to as the (1, J) reference point using grid coordinates, and the data block in which the display reference point (1, J) is located at the upper left corner will be referred to as the (1, J) block. It is assumed that the large-capacity image data 6 is stored in two parts each block 8 as a unit. Next, the difficulty of reading out the display image data area 9 will be explained.

From the operation unit 4 to the starting point (P,) 10 of the display image data area 9
-1 and the resolution d are specified, the control 2 section 5 determines a data block including the display image data area 9.

That is, the position of the starting point P of the display image data area 9 is (
i, j), then the data block containing P is as follows.

Here, (M×N) is the size of data block 8, (V×
H) is the number of display pixels for one screen of the display device, and d is the display resolution on the image data 6. As a result, 1,≦1≦12
, J, ≦J≦J2, it is only necessary to access the data block (1, J) within the range by determining the address using the table. FIG. 3 is an explanatory diagram of the readout range of data from the data block 8 including the boundary of the display image data area 9, where 'a}, 'd, {d, and (g} are blocks (1,, 1, ), (12, J2), (1
3, J3), (14, J4) reading range, {b',
'Kawama blocks (1,, J), (12, J), however, the reading range of J, ≦J≦J2, [d', (h) is
Blocks (1, J,), (1, J2), but 1, respectively
The reading range of the SIS12 is shown.

In each figure 'a' to (h), parts 1 and 4 are given as follows.
However, mod (x, y) indicates the remainder of x modulo y.

) By reading out the data at the pixel position corresponding to the resolution d from the data in the display image data area 9 determined above, it is possible to display any image area in the large capacity image data 6 with any precision. Become.

Here, if the resolution d is 1'2, every other pixel is set, and if the resolution d is 1'3, every other pixel is
If every pixel, . . . , 1/k, data in the image data is sampled every (k-1) pixel. FIG. 4 is a block diagram showing the configuration of one embodiment of the control section 5.
12 is a calculation section, 12 is a table circuit section, and 13 is a block buffer.

The calculation unit 11 calculates the female point P. of the display image data area 9, which is input information from the operation unit 4. Using the coordinates (i, j) of
≦J2). The table circuit unit 12 has an address conversion table that indicates the correspondence between the block number and the start address indicating the storage location of each block data in the large-capacity image memory, and uses the address conversion table to convert large block data. Read from capacity image memory to block buffer 3. The arithmetic unit 11 calculates
Each data read range shown in FIG. 3 is calculated according to the formula, and only data within the data read range is sampled according to the resolution d and sent to the refresh memory 2. Blocks that do not include the boundaries of the display image data area 9
Data is sampled according to resolution d and sent to refresh memory 2. The arithmetic unit 11 can be easily realized using a known technique by using a microprocessor. Furthermore, the table circuit section 12 and block buffer 3 can be easily realized using known memory control techniques.
Refresh memory 2 stores the sent data.
Next, display image data is formed by arranging the data, and the image is displayed on the display unit 3 by refreshing the data using a conventional method.

The present invention is particularly effective because a large amount of image data is encoded, the amount of data is compressed, and the data is stored in the image file 1.

That is, when encoding image data and storing it in a file, it is generally possible to associate the position of a two-dimensional image with the encoded data by decoding the encoded data. Therefore, it has been difficult to access encoded data corresponding to a required pixel position at high speed when using large-capacity image data.However, as in the present invention, image data is divided into data blocks, and the data・By aligning the start position of the block with the reference point on the two-dimensional image as a display reference point and encoding the image data in units of data blocks, the decoding process is shortened and access to the required data is made easier. It becomes possible to perform the process at high speed. Even for encoded image data, access to data block 8 is performed according to equation {1-.

Further, the readout range from the data block 8 including the boundary of the display image data area 9 is determined by '2} after decoding the encoded image data onto the block buffer 13.
It can be done according to the formula. Note that although the above description has been made regarding a refresh type display device, it goes without saying that the present invention can also be applied to a storage type display device.

As explained above, according to the present invention, by providing a plurality of display reference points in large-volume image data in association with two-dimensional images, any area in large-volume image data can be displayed with any precision. It has the advantage of being able to display efficiently.

[Brief explanation of the drawing]

FIG. 1 is a block configuration diagram of an embodiment of the image display device of the present invention, FIG. 2 is an explanatory diagram for explaining the relationship between image data and display reference points, FIG. 3 is an explanatory diagram for explaining the data read range, and FIG. FIG. 4 shows a block diagram of an embodiment of the control section according to the present invention. 1...Image data file, 2...Refresh
Memory, 3...Display unit, 4...Operation unit, 5...Control unit, 6...Image data, 7...Display position reference point,
8... Data block, 9... Display image data area, 10... Display image data area vertex, 11... Arithmetic unit, 12... Table circuit unit, 13... Block buffer. Figure 7 Figure 2 Hair 3 Figure 4

Claims (1)

[Claims] 1 In an image display device that extracts data from an image and displays it on a display unit, an image file device stores continuous image data larger than one display data in data compression encoded form, and An address conversion table showing the correspondence between the coordinates of the display position reference point installed in An image display device comprising: a control section that reads image data corresponding to one display at a data sampling density; and a display section that displays the read image data for one display.