JPH04123581A - Simple double buffer display device - Google Patents

Abstract

PURPOSE:To realize a simple double buffer display device offering fast and easy processing with simple constitution by providing a means converting a written still picture data and a means to rewrite a content of a lookup table so as to obtain a desired direction effect when a still picture data by two converted patterns is displayed on the display device. CONSTITUTION:A picture data of still pictures 1, 2 is written in a frame memory 10. Then according to a command of a host computer 18, in order to a desired direction effect as to a picture, the data of the pictures 1, 2 is read in the lump in a form of 8-bit data and a lookup table section 12 converts the integrated data of the pictures 1, 2 into 8-bit picture data of the pictures 1, 2 according to the content of the lookup table. Then a display controller 14 based on the 8-bit data of the converted pictures 1, 2 displays the pictures 1, 2 onto a screen of a monitor 16 in a way of R, G, B full color. Thus, the simple double buffer display device implementing fast and simple processing is realized without use of a complicated picture arithmetic processor.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a simple double-buffer display device, which is suitable for use in obtaining desired effects for, for example, still image television video programs, especially video programs that require a large capacity frame memory such as high-definition. Use a double-buffered display device.

[Conventional technology]

When producing a still image television video program, such as a high-definition video program, when switching from one still image being displayed to the next still image, various production processes, such as wipe processing, are performed to obtain a desired production effect. There are cases. Conventional techniques used for such production processing include those that use frame memory (single-buffer frame memory) consisting of memory for one still image screen, and those that use memory for two still images (each screen Some use a frame memory (double-buffer type frame memory) having two separate memories called front memory and back memory. In the technology using the single-buffer frame memory mentioned above, still image data stored in various disk devices, etc., is read out one by one and transferred to the frame memory, and the processing of the still image data is devised during the transfer. This is done in a variety of ways, and various effects are applied. In addition, in the double-buffer type frame memory, still image data is transferred from each of the disk devices to the back memory, image data is transferred from the layer memory to the front memory, and images between the front memory and the back memory are transferred. The data is inverted and various effects are applied.

Problem to be Solved by the Invention 11NI However, when using the single buffer type frame memory, since still image data is transferred one by one to the frame memory, there are considerable restrictions on the performance effect function. There is a problem in that it is only possible to achieve a performance of the width. Furthermore, in the double-buffer type frame memory, in addition to wiping, it is also possible to realize various effects such as cut switching and fade switching. However, in order to realize this double-buffered memory frame for still image data consisting of a large amount of image data, such as a high-definition still image, a frame memory with a capacity of 12 Mbytes or more is usually required. In addition, for example, in order to perform dissolve processing, a separate dedicated image processing processor is required, resulting in a complicated and expensive device configuration. Furthermore, when performing performance techniques such as dissolve using a double-buffer frame memory, high-speed arithmetic processing is difficult due to the large amount of data to be handled. The present invention has been made in order to solve the above-mentioned conventional problems, and it is possible to use a single-buffer frame memory with a relatively simple configuration to create complex effects similar to those of a double-buffer frame memory. At the same time, it is a simple and easy-to-use system that allows you to perform effects techniques such as dissolves, which were difficult to perform at high speed with conventional double-buffer frame memory, with a simple configuration and without the use of a special processor. An object of the present invention is to provide a double buffer display device. [Means for Solving the Problems] The present invention provides a device for displaying still image data written in a single-buffer type frame memory on a display screen with a presentation effect, in which each pixel in the frame memory Means for writing still image data consisting of pixel data of half the number of bits of each unit memory storing data into the frame memory for two screens; Means for converting pixel data of the number of bits of the unit memory into two screens worth of still image data by referring to an up-table, and a desired effect when displaying the converted two screens worth of still image data. The above problem is solved by providing means for rewriting the contents of the lookup table so that the lookup table is obtained.

[Effect]

In the present invention, when displaying still image data written in a single-buffer type frame memory on a display screen, pixels with a number of bits that is half the number of bits of each unit memory storing each pixel data in the frame memory are used. Two screens worth of still image data consisting of data is written to the frame memory, and the written still image data is read as a still image data for two screens consisting of pixel data of the number of bits of the unit memory by referring to a lookup table. Convert to image data. During this conversion, the contents of the lookup table can be rewritten, so that the still images of two screens can be displayed independently, cut switching, fade-in, and fade-out processing can be performed, and each screen can be combined with the desired brightness. Various effects such as dissolving the image and dissolving the image are displayed. Therefore, since it is possible to handle image data like a double-buffer frame memory using a single-buffer frame memory with a relatively simple configuration, there are no restrictions on production functions as in the past, and various complicated functions can be handled. You can get a dramatic effect. In addition, effects techniques such as dissolves, which are difficult to perform at high speed with the conventional double buffer system, can be performed easily and at high speed with a simple configuration without using an image arithmetic processor.

[81st Example] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. This embodiment uses lookup table control to display two still images (Image 1, Image 2) individually or in a combined manner.
This is a simple double-buffer display device configured as shown in the figure. As shown in FIG. 1, this simple double-buffer display device mainly includes a frame memory 10, a look-up table (LUT) #12, and a display controller 1.
4, a monitor (display unit) 16, and a host computer 1
8 is provided. The frame memory 10 has red (R), green (G), and blue (
B) 1920 pixels horizontally that can store one screen worth of still image data consisting of 8-bit pixel data for each of the three primary colors.
It is a frame memory having a size of 1035×1035 pixels (vertical). When storing still image data for two screens in the frame memory 10, R,
In a unit memory that stores 1 pixel data of frame memory of 8 bits each for G and B, 4 bits of still image (image 1, image @ 2) data are written in the upper 4 bits and lower 4 bits respectively. The data of image 1 and image @2 to be written need only be 4-bit data at the time of writing, and it is possible to write image data originally consisting of 8-bit data as 4-bit still image data. can. In this case, for example, as shown in FIG.
The upper 4 bits of the 8-bit image data of image 2 are written to the upper 4 bits of the unit memory, and the upper 4 bits of the 8-bit image data of image 2 are written to the lower 4 bits of the unit memory. Write. Thereby, still image data for two screens can be written into the frame memory 10 in the form of pixel data of half the number of bits of the unit memory. In addition, by using the upper 4 bits of the original 8-bit data in this way, the upper 4 bits represent the characteristics of the data, but the image quality deterioration caused by the removal of dirt from the 4-bit data can be minimized. It can be stopped. Also, of course, 4-bit data can be used as the original still image data. When this 4-bit image data is used, it can be easily handled because it can be written into the upper and lower 4 bits of the IT frame memory. The look-up table unit 12 stores a look-up table, and reads the image data of 4 bits each of image @1 and image 2 stored in each unit memory of the frame memory 10 at once in 8 bits. , the data of image @1 and image 2 read with reference to the lookup table are converted into 8-bit format and output. Furthermore, by rewriting the contents of the lookup table, a desired presentation effect can be obtained. Here, the lookup table is, for example, shown in Figure 3 (A), (
Those shown in B) can be used. Note that in the same figure or in Figure 6, etc., the horizontal axis represents the data (○ to 255) grouped in 8 bits of the unit memory.
The upper 4 bits are 0.16.32 to 24.
0 and the lower 4 bits correspond to 0 to 15, and the vertical axis is the luminance signal. Also, the lookup table in Fig. 3(A) has the upper 4 bits (16 out of 0~255, such as 16.32.48...
output data according to the value of
Figure (B) shows the lower 4 bits (0 to 15.0.1.2.3.
0, which allows output data to be obtained according to the value of
For example, when displaying image 1, the data of image 1 stored in the upper 4 bits (16 to 255) of the unit memory is converted to 8 bits (0 to 255) by referring to the lookup table shown in FIG. 3(A). ) is converted to luminance data. In addition, when displaying image 2, the data of image gA2 stored in the lower 4 bits (0 to 15) of the unit memory is converted into 8 bits by referring to the lookup table shown in FIG. 3(B), for example. It is converted into the displayed luminance data (0 to 255). As will be described later, when you want to display only image 1, use the step-like lookup table in Figure 3 (A), and when you want to display only image 2, use the diagonal lookup table in Figure 3 (B). Only content consisting of lines is converted using a lookup table. Further, the contents of the lookup table for applying various other effects will be explained in detail later with reference to FIG. 6 and the like. The post computer 18 includes the frame memory 1
0 and the lookup table unit 12 to instruct read and write processing of image data in the foam memory 10 and rewrite processing of the contents of the lookup table in order to obtain a desired production effect. It is something. The display controller 14 displays the converted image 1, image! The 8-bit still image data of Image 2 is transferred to the monitor 16, and Image 2 of Image 1 is displayed in full color on the monitor screen. Next, the operation of the embodiment will be explained. In the simple double-buffer display device according to this embodiment, processing from writing and reading image data in the frame memory 1o to displaying it with a predetermined effect is carried out according to the procedure shown in FIG. That is, first, the image data of the still image 1.2 is written into the frame memory 18 (step 1), and this image data is
As shown in FIG. 2, it is 8-bit data consisting of full colors of R, G, and B. The upper 4 bits of one image data are written to the upper 4 bits of the unit memory from 8 bits 1 in the frame memory 10, and the image is The upper 4 bits of 2 data are written to the lower 4 bits of the unit memory, and the written state is schematically shown in FIG. 5(A). Next, in accordance with instructions from the host computer 18, a lookup table with contents as shown in FIG. (Step 2). Next, the image 1.2 data in the frame memory 10 is
The readout data is read out all at once in the form of data and input into the lookup table section 2 (step 3). Next, the look-up table unit 12 stores the image 1.2.
By referring to the lookup table, the summarized data is converted to image 1 according to the contents of the lookup table.
．． 2 into 8-bit image data (step 4). Next, the display controller 14 displays the image 1 and the image gIA2 in full colors of R, G, and B on the screen of the monitor 16 based on the converted 8-cut data of the image 1.2 (step 5). Next, it is determined whether or not to end the image display at this time (step 6), and if the display is to be continued, the process returns to step 2 to write or rewrite the contents of the lookup table.
On the other hand, if the process is to be terminated, the procedure shown in FIG. 4 is terminated. In addition,
For example, when performing fade-in, fade-out processing, or dissolve processing, which will be described later, to display images 1 and 2 while changing their brightness over time, one or more steps (steps) are performed depending on the time interval of screen switching. Every time steps 2 to 6) are completed, the contents of the lookup table are rewritten. Next, various production effect processing by rewriting the contents of the lookup table 12 will be explained. First, an example of the contents of a lookup table for performing cut switching (when switching display images, one image is erased and the other is displayed) is shown in Figure 3<A). , When instantaneously cutting and displaying 6 images @ 1 and 2 as shown in (B), first write the contents of Fig. 3 (A) in the lookup table. , the image 1.2 data stored in the frame memory 10 as shown in FIG. This read data is converted to 8-bit data by referring to the lookup table shown in FIG. 3(A), and as shown in FIG. 5(B), only the data of image 1 is displayed. Write the contents shown in FIG. 3(B) into the table section 12. Next, the image 1.2 data in the frame memory is written in 8-bit format into the look-up table section 12.
This data is converted into 8-bit data by referring to the lookup table shown in Fig. 3 (B), and then converted into 8-bit data as shown in Fig. 5 (
In this way, only the data of image 2 is read out as shown in C), so that a cut switching effect can be created as if instantaneously switching from image 1 to image f&2. In addition, an example of the contents of a lookup table for creating a fade switching effect (when switching display images, the brightness of two images is changed and displayed on the monitor screen) is shown in Figure 6 (
In this production effect shown in A) and (B), each time the 4-bit image 1.2 data is converted to 8-bit data, the slope of the lookup table is changed as shown by the arrow in Figure 6. By changing and rewriting the image, one image is erased W1 (the lookup table for the image to be erased is not written), and the image gradually becomes brighter (fade in) and gradually darkens ( When trying to fade in as shown in Figure 6 (A) and (B), the tilt of the lookup table should be brought closer to the vertical direction, and on the other hand, when trying to fade out, the lookup table can be All you have to do is let the inclination lie down. Also, dissolve processing (when switching display images, the brightness of the initially displayed image fA1, for example, is gradually lowered (darkened), and then the image to be displayed next, for example gA2, is changed to
Gradually increase the brightness (brighter) to create image 1.
FIG. 7 shows an example of the contents of a look-up table for applying the effect of changing the display to show the image @2 through the image. The lookup table for performing this dissolve processing is the lookup table for fade in and fade out shown in Figures 6 (A) and (B) above.
In FIG. 7, the components for image 1 of the look-up table are shown by a dashed-dotted line, and the components for image 2 are shown by a dashed-dotted line. For example, when switching from image 1 to image 2 by dissolving, the slope of the step of the lookup table component for the initial plane ff1l is maximized or strong, and the slope of the lookup table component for the image t&2 is set to the maximum or strong slope. is set to the minimum or weakest, and the lookup table is rewritten so that the step is gradually weakened for image gA1 and the slope is strengthened for image 2. Note that the conversion rate of the lookup table component of image 1 is (ratio of converted data value to original data) and the conversion rate of the lookup table component of image 2 should always be 100%.1 For example, if the lookup table component conversion rate of image (!1 is 90%) %, the lookup table component conversion rate of image 2 is set to 10%.In Figure 7, image 1:
This shows the case where t, 2 is approximately 50% = 50%. In this way, one image, for example, image 1, is gradually darkened, and the other image, for example, image 112, is gradually brightened. , it is possible to perform a dissolve effect in which both are transparent and combined. Note that the frame memory 10 according to this embodiment can originally be used in a single buffer system, and by selecting the contents of the lookup table, a dissolve effect can be performed. The mode used in the buffer method (single mode) can be switched to the simple double buffer (double buffer mode) display according to the present invention.In other words, the unit is displayed as shown schematically in FIG. 8(A). When 8-bit image data A is initially stored in the memory and the image is displayed in single mode, the image data A in the unit memory can be retrieved using the lookup table shown in Figure 3 (A) above. As shown in FIG. 8(B), leave the upper 4 bits data A1 and discard the lower 4 bits data A2. Next, write the 4 bits data of image B into the lower 4 bits in the unit memory. In this case, for example, Image A1 can be displayed by referring to the lookup table in Figure 3 (A) (Figure 8 (D)).
, Image B can be displayed by specifying the lookup table in Figure 3 (B) (Figure 8 (E), that is, it can be displayed in double buffer mode, and various effects processing can be performed by rewriting the lookup-pull contents. On the other hand, if you want to return the double buffer mode to the single buffer mode, first discard the lower bit image B data in the unit memory using the lookup table in Figure 3 (Figure 8). (F) Insert the lower 4 bit data A2 of image A into the empty space (Fig. 8 (G)). This allows use as a single buffer mode in which the 8 bit data of image @A is not stored in the frame warp. In the above embodiment, color image data of 2A consisting of 4 bits is divided into 2A of color image data consisting of 4 bits using a lookup table.
An example is given of a case where various processes are applied to convert color image data into a sheet of color image data. When converting 8-bit image data to 4 bits, deterioration in image quality is unavoidable, but it is extremely useful when presentation is given priority over image quality.1 For example: There is a method in which 4-bit data is written in a vacant part of an audio data frame on a so-called compact disc used for audio reproduction, and image information that has been subjected to various effects processing along with the audio signal is obtained. By applying the present invention to such image data with a restriction on the number of bits, it is possible to provide a wide variety of performance functions. However, the number of bits of the frame memory in carrying out the present invention is not limited to 8 bits, and the present invention can be carried out in other frame memories of, for example, 16 bits or 32 bits.

【Effect of the invention】

As explained above, according to the present invention, it is possible to perform the same effect processing as the double-buffer method using a single-buffer method frame memory. An excellent effect is that it is possible to perform production techniques such as dissolve processing, which are difficult to perform at high speed with memory, at high speed, simply, and economically without using a special expensive and complicated image processing processor. is obtained.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the overall configuration of a simple double-buffer display device according to an embodiment of the present invention, and FIG. 2 is a block diagram showing the structure of a unit memory in a frame memory for explaining the operation of the embodiment. FIG. 3 is a plan view schematically showing examples of pixel 4 and cut data of images 1 and 2; FIG. 3 is a diagram showing an example of a look-up table used for cut switching in the device; , Similarly, FIG. 5 is a plan view schematically showing the state of each data stored in the unit memory. Similarly, FIG. FIG. 7 is a diagram showing an example of a look-up table when performing switching processing; FIG. 7 is a diagram showing an example of a look-up table when performing resolve processing with the device; FIG. FIG. 3 is a plan view schematically showing an example of a memory state when the device is switched between single mode and double mode. 0... Frame memory, 2... Lookup table, 4... Display controller, 6... Monitor, 8... Host computer.

Claims (1)

[Claims] (1) Number of bits of each unit memory storing each pixel data in the frame memory in a device for displaying still image data written in a single-buffer type frame memory on a display screen with a presentation effect. Still image data consisting of pixel data with half the bit number of 2
means for writing into the frame memory the number of screens, and converting the written still image data into two screens worth of still image data consisting of pixel data of the number of bits of the unit memory by referring to a lookup table; and means for rewriting the contents of the lookup table so that a desired effect is obtained when displaying the converted still image data for two screens. A simple double-buffer display device.