JPS62232688A - Image processor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention is capable of displaying the image by reading out predetermined partial images stored in each memory and superimposing these images on an image display means. The present invention relates to an image processing device that displays a certain image on the device.

[Conventional technology]

It is used when In this case, the background as a constituent part of the image to be displayed is stored in the first frame memory, the mountain is stored in the second frame memory, and
The sun is stored in a third frame memory, and the background is extracted from these frame memories.

The entire image is displayed on the image display means by sequentially reading out the mountain and the thick part and displaying these on the display image means. In this case, it is set in advance which frame memory the contents are read out first.

FIG. 2 shows the configuration of such an image processing device.

In the figure, 1 and 2 indicate frame memories. These frame memories 1.2 store image data corresponding to each partial image to be displayed in an overlapping manner.

Here, each of these frame memories 1 and 2 stores image data for one screen.

Therefore, for example, if a mountain image is stored in frame memory 1,
When the sun image is stored in the frame memory 2, "0" is stored.

3.4 indicates a register provided after each of the frame memories 1 and 2 described above. Each of these registers 3 and 4 temporarily stores each image data output from each of the frame memories 1.2.

5.6 shows a look amplifier table provided after each of the registers 3 and 4 described above. Each of these lookup tables 5.6 outputs image color data corresponding to each image data output from each register 3.4.

7 indicates selection means. The selection means 7 gives priority to one of the two image color data and outputs it to the subsequent image display means 8 for display. in this case,
Other image color data are output to the image display means 8 later.

Reference numeral 9 indicates a ranking determining means for controlling the selecting means 7. The ranking determining means 9 determines which of the two image color data is to be displayed first in the frame memory 1.
, 2.

Further, 10 is a control signal generation circuit, which generates control signals necessary for the image display means 8 inside the image processing device,
Thus, the storage address of the image data stored in the frame memories 1 and 2 and the display position of the image display means 8 are operated to be uniquely determined.

The data converter A is constituted by the registers 3 and 4, the lookup table 5.6, the selection means 7, and the ranking determination means 9. The data converter A converts the image data stored in the frame memories 1 and 2 into image color data and outputs the image color data to the image display means 8.

Next, the operation will be explained.

The image data stored in the frame memory 1.2 is sequentially read out in accordance with the address signal specified by the control signal generation circuit 10 and sent to the registers 3 and 4. The image data stored in these registers 3.4 are
This is the input to lookup table 5.6, and the output is:
Image color data corresponding to the input image data is sent out.

The image color data sent from these lookup tables 5 and 6 is applied to selection means 7 and ranking determination means 9.

The ranking determining means 9 determines whether the image color data of the frame memory with a high priority specified in advance has a color (for example, if the image color data is all "0", it is determined that there is no color), If there is a color, the selection means 7 operates to select image color data with a high priority. on the other hand,
If there is no color, the image color data in the frame memory with a lower priority is selected. Ranking determination means 9
By repeating the above operation for each display pixel,
Images are superimposed pixel by pixel and an image signal is sent to the image display means 8.

[Problem that the invention seeks to solve]

However, the image processing apparatus according to the prior art has the following problems.

That is, when displaying a plurality of images in a superimposed manner, it is necessary to have lookup tables equal to the number of images to be superimposed. Further, the number of elements of the selection means 7 depends on the bit width of the image color data, but since the bit width of the image color data is several times larger than the bit width of the image data, there is a problem that the number of elements increases. was there.

Here, the reason why the number of elements of the selection means 7 depends on the bit width of the image color data is as follows.

That is, assume that image data for one pixel is 4 bits, and this is converted into 12-bit image color data (image color data corresponds to three primary colors) using lookup table 5.6. In this case, in order to superimpose the images in the two frame memories 1.2 pixel by pixel, it is necessary to convert 12 bits×2=24 bits into 12 bits.

If the image color data is 18 bits, 18 pinot) x 2 =
It is necessary to change 36 bits to 18 bits.

[Means for solving problems]

The data converter in the present invention includes a selection means that sequentially selects one memory based on the determination result of the ranking determination means and outputs the image data of the memory, and converts the image data outputted by the selection means into image color data. It consists of a lookup table that is converted and output.

[Effect]

The selection means sequentially selects one memory and outputs the image data of the memory. The lookup table converts the image data selected by the selection means into image color data,
The image is displayed on the image display means.

〔Example〕

Embodiments of the present invention will be described below with reference to FIG. Note that the same components as those in the prior art are given the same reference numerals, and the description thereof will be omitted.

However, 11 indicates a selection means according to the present invention.

The selection means 11 is provided after the registers 3 and 4,
Each image data is input from both registers 3 and 4, and one of the image data is selected and output.

The selection means 11 determines from which register 3 or 4 image data is to be selected based on the output of the ranking determination means 12. Here, the ranking determining means 12 controls the selecting means 11 to select the image data of the frame memory 1 or 2 having a high priority specified in advance.

Further, reference numeral 13 denotes a second output table provided after the selection means 11. Word lookup table 1
Reference numeral 3 converts the image data selected and output by the selection means 11 into image color data and outputs it to the subsequent image display means 8.

The register 3.4, the selection means 11, the look-up table 13, and the ranking determination means 12 constitute a data conversion section B. The data converter B converts the image data stored in the frame memory 1.2 into image color data and outputs the image color data to the image display means 8.

Next, the effect will be explained.

The image data read from the frame memory 1.2 is temporarily stored in registers 3 and 4. Further, the read image data is applied to the selection means 11 and the ranking determination means 12. The ranking determining means 12 determines which frame memory 1 or 2 image data is to be selected, based on a table showing the correspondence between image data and image color data as to whether or not they have colors.

The selection means 11 selects image data and sends the selected image data to the lookup table 13 according to instructions from the ranking determination means 12 .

The lookup table 13 reads image color data corresponding to the image data and sends it to the image display means 8.

However, in this embodiment, the selection means 11 is provided before the lookup table 13, and the selection means 1
Since image data is input to the selection means 11, the number of elements in the selection means 11 can be small. In contrast, the selection circuit of the prior art had a large number of elements because the image color data was manually input.

Further, as described above, the lookup table 13 is located after the selection means 11. Therefore, the selection means 11
The image data selected by the selection means 11 is inputted to the . Therefore, the look amplifier table 13
It is not necessary to provide the same number of frame memories 1.2 as in the prior art, but one is sufficient.

In the above embodiment, the case where there are two frame memories 1 and 2 has been described, but the number of frame memories is the same as the number of images to be overlapped.

〔Effect of the invention〕

As explained above, according to the present invention, the selection means is provided before the look amplifier table, and the look amplifier table converts the image data selected and outputted by the selection means into image color data, and converts the image data selected and outputted by the selection means into image color data, Since the image is displayed in color, the following effects can be achieved.

That is, since the selection means handles image data having a smaller number of bits than image color data, the number of elements can be reduced compared to the selection means of the prior art.

Further, since the look-up table converts the image data selected by the selection means into image color data, it is not necessary to provide it for each memory as in the prior art, and only one look-up table is required.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a block diagram showing a conventional technique. 1.2... Memory (frame memory), 8... Image display means, 11... Selection means, 12... Rank determining means. Agent Masuo Oiwa (and 2 others) Figure 1

Claims (1)

[Scope of Claims] A plurality of memories that store image data of respective partial images constituting one display image, a data conversion unit that sequentially converts the image data of these memories into image color data, and the data conversion unit In an image processing device comprising an image display means for displaying an image in color based on outputted image color data, the data converting section comprises a ranking determining means for determining the selection order of the memory, and a determination by the ranking determining means. Based on the results 1
a selection means for sequentially selecting the memories of the memory and outputting the image data of each memory, and a selection means provided after the selection means, converting the image data outputted by the selection means into image color data and displaying the image data on the image display means. An image processing device comprising: a lookup table to output.