JPH06335022A - Still picture storage device - Google Patents

Abstract

PURPOSE:To provide still picture storage device storing graphics data and video data while overlapping them without deterioration in picture quality. CONSTITUTION:Graphics data drawn to picture memories 2, 3 by a processor 1 are overlapped by using a data selector 8 and a lookup table 9 according to the detection of a transparency detection section 7. Video data decoding an NTSC signal and graphics data processed in a form suitable for storage by an arithmetic operation circuit 10 are overlapped by a data selector 11 and stored in a frame memory 103 according to the control of a frame memory control section 12. A still picture called by the frame memory section 103 is outputted as both of the NTSC signal and the digital data from a still picture output section 104.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a still picture storage device for superimposing and storing still picture video data and graphics data such as characters and figures.

[0002]

2. Description of the Related Art FIG. 7 is a block diagram showing a conventional still picture storage device for storing video data of one still picture.
In the figure, reference numeral 21 denotes NTSC as a television signal.
A decoder for converting a composite signal (hereinafter, simply referred to as NTSC signal) into RGB (red, green, blue) signals, and 22 is an A / D for converting the RGB signals into digital video data.
It is a converter, and the video data generation unit 2 together with the decoder 21.
00 is configured. 23 is the above video data in RGB
A frame memory unit that stores one frame for each image of
24 is a frame memory unit 22 based on an instruction from the outside.
A frame memory control unit that controls writing and reading of video data to and from the frame memory unit; 25 is a D / A converter that converts the RGB video data read from the frame memory unit into an analog signal; and 26 is an original RGB analog signal. NT
D / A converter 2 which is an encoder for converting to SC signals
5 and 5 constitute a still image output unit.

Next, the operation will be described. During the still image storing operation, an analog NTSC signal input from the outside is converted into an RGB signal by the decoder 21. This RGB
The signal is converted by the A / D converter 22 into digital video data having a form in which RGB data exists for each dot clock, as shown in FIG. The frame memory control unit 24 divides the digital still image data for one screen of the designated storage area of the frame memory unit 23 into RGB data and stores the data.

During the display operation, the frame memory controller 2
Reference numeral 4 calls the digital still image data for one screen in the designated area from the frame memory unit 23 in the same form as in FIG. The D / A converter 25 converts this digital still image data into analog still image data, and the encoder 26 converts it into an NTSC signal and outputs it.

FIG. 9 is a block diagram showing a conventional image superimposing device for superimposing one video data and two graphics data. In FIG. 9, 27 is a processor for producing two graphics data A and B. Lookup tables A and B for expanding the RGBI 8-bit graphics data based on the RGBI (red, green, blue, luminance) 1-bit graphics drawing data
Is. 28 is digital graphics data A, B
A transparent detection unit for detecting a transparent portion other than the portion drawn from the reference numeral 29, and RG from the look-up tables A and B27.
A data selector that switches the B data according to the detection of the transparency detection unit 28, and a data selector 30 that switches the data from the data selector 29 and the RGB video data according to the detection of the transparency detection unit 28.

Next, the operation will be described. The RGBI 1-bit drawing data created by the processor is input to the lookup tables A and B 27 in the form shown in FIG. The look-up tables A and B27 are expanded to 8-bit RGB data as shown in FIG. 11 and output in the same form as the video data shown in FIG. At the same time, the transparency detector 28 detects transparency data in which each RGBI bit is 0 and outputs a switching signal. The data selector 29 selects high priority digital graphics data A or B according to the switching signal. The digital graphics data and the video data edited in this way are overlapped by being switched by the data selector 30 in the next stage in accordance with the switching signal output from the transparency detector 28.

[0007]

Since the conventional still picture storage device is constructed as described above, since the still picture is stored as RGB digital still picture video data, the frame memory 23 is used. The number of In addition, when digital graphics data such as characters is to be superimposed on a video still image, an image superimposing device as shown in FIG. 9 is required outside the still image storage device. Further, when performing image superposition control, it is necessary to re-decode the still image output from the still image storage device as an NTSC signal, perform A / D conversion into digital still image data, and then perform superimposition. Therefore, there is a problem that the capacity of the lookup tables A and B 27 increases and the image quality of the still image deteriorates.

The invention of claim 1 has been made in order to solve the above problems, and obtains a still picture storage device capable of storing graphics data and video data as digital still picture data by superimposing them. With the goal.

It is an object of the present invention to provide a still picture storage device capable of reducing the frame memory.

It is an object of the present invention to obtain still image data with little deterioration and to obtain a still image storage device capable of monitoring a still image.

It is an object of the present invention to provide a still picture storage device capable of easily superimposing graphics data and video data.

It is an object of the present invention to provide a still image storage device capable of reducing a look-up table for converting the form of graphics data.

[0013]

According to another aspect of the present invention, there is provided a still image storage device including a graphics data generating section for generating a plurality of digital graphics data and a video data generating section for decoding a television signal to digitize it. Section, a superposition control section that superimposes the data generated by the graphics data generation section and the data generated by the video data generation section and outputs as luminance / color difference data, and a frame memory section that holds the luminance / color difference data. And are provided.

A still image storage device according to the invention of claim 2 is
The digital graphics data is converted into the same format as the video data and then superimposed.

A still image storage device according to a third aspect of the present invention is
A still image output unit for outputting the still image data read from the frame memory unit and the original television signal restored from the still image data is provided.

A still image storage device according to a fourth aspect of the present invention is
A lookup table for converting graphics data as primary color / luminance data into luminance / color difference data is provided.

A still image storage device according to the invention of claim 5 is
By switching the graphics data and the video data obtained from the look-up table on the basis of the signal in which the transparent portion of the graphics data is detected, the two data are superposed.

[0018]

In the still picture storage device according to the present invention, since the digital data is superposed, the superposed image of the graphics data and the video data can be stored without deterioration of the image quality, and the digital luminance / color difference can be stored. Since an image in which graphics data and video data are superposed is stored as data, the number of frame memory units can be reduced.

According to the second aspect of the present invention, in the still image storage device, the graphics data and the video data are converted into the same luminance / color difference data form as the video data before the data is superposed, and the data after the superposition is converted. Can be stored as luminance / color difference data, so that the frame memory can be reduced.

In the still picture storage device according to the third aspect of the present invention, the digital still picture and the television signal can be simultaneously obtained from the still picture output section.

In the still image storage device according to the fourth aspect of the present invention, the look-up table can easily convert the form of graphics data into the same form as video data.

In the still picture storage device according to the fifth aspect of the present invention, by switching to the video data at the transparent portion of the graphics data, the two data can be easily overlaid and the lookup table can be reduced.

[0023]

EXAMPLES Example 1. An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 100 denotes a graphics data generation unit for generating two graphics data, each of which is RGBI data as two primary color / luminance data, based on an external drawing control command.
Reference numeral 01 is a video data generation unit that generates video data of luminance / color difference data from the NTSC signal, and 102 is two graphics data generated by the graphics data generation unit 100 and video data generated by the video data generation unit 101. A superposition control unit for performing superposition control, 103 is a frame memory unit that stores an image of one frame superposed by the superposition control unit 102 separately into luminance Y and color difference data C, and 12 is a frame memory unit. A frame memory control unit that controls writing and reading of data to and from 103, and a frame memory unit 1
03 is a still image output unit that outputs the still image.

In the graphics data generation unit 100, 1 is a processor that draws image data and controls data setting in a look-up table 9 and a frame memory control unit 12, which will be described later, and 2 stores image data with high priority. The image memory 3 for serial output outputs image data having a low priority and serially outputs the image data.

In the video data generation unit 101, 4 is an NTSC signal for luminance / color difference analog video data Y, R.
NTSC-luminance / color difference decoder for converting into Y, BY, 5 is an A / D converter for converting the above Y, RY, BY data into digital data, and 6 is a parallel R-
It is a parallel-serial conversion circuit (P / S) that converts Y, BY digital data into serial data.

In the superposition control unit 102, 7 is a transparent detection unit for detecting a transparent portion from two graphics data from the image memories 2 and 3, and 8 is an image memory 2 and 3.
The data selector for switching the graphics data of 8 in accordance with the detection of the transparency detection unit 7, and the control unit 9 controls the data from the data selector 8 together with the data from the transparency detection unit 7 into 8-bit Y, RY, B A double-capacity look-up table for converting to -Y data, and 10 is an arithmetic circuit for arithmetically processing Y, RY, and BY graphic data from the look-up table 9 and converting it into a form suitable for storage. , 11 are data selectors that switch the graphics data from the arithmetic circuit 10 and the video data from the video data generation unit 101 in accordance with the detection of the transparency detection unit 7 and send them to the frame memory control unit 12.

In the still image output unit 104, a serial-parallel conversion circuit (S / P) for converting the serial color difference data C composed of RY and BY read from the frame memory unit 103 into parallel data, Reference numeral 14 is a D / A converter that converts the luminance data Y read from the frame memory unit 103 and the RY and BY data from the serial-parallel conversion circuit 13 into analog signals, and 15 is digital data Y. , RY, BY are encoders for converting to NTSC signals. In addition, the still image output unit 10
Reference numeral 4 is adapted to output the luminance data Y and the color difference data C as digital data as they are. In addition,
Numerical values “4” and “8” on the line in FIG. 1 indicate the number of bits.

FIG. 2 shows a form of data output from the double-capacity lookup table 9 shown in FIG. FIG. 3 shows a form of data output from the arithmetic circuit 10 in FIG. FIG. 4 shows that the NTSC signal is decoded into analog video data of luminance / color difference Y, RY, BY by the NTSC-luminance / color difference decoder 4 and digitized by the A / D converter 5 to obtain digital video data. It is a form. Figure 5
Is a form of digital color difference data C multiplexed by the parallel-serial conversion circuit 6 in FIG. FIG. 6 shows the form of data stored in the lookup table 9 shown in FIG.

Next, the operation will be described. First, the operation of the graphics data system will be described. The processor 1 draws image data having a high priority in the image memory 2 and image data having a low priority in the image memory 3 by using RGBI (red, green, blue, luminance) 1-bit data for each pixel, for example. Also, the processor 1
Sets the luminance / color difference data for the image memory 2 and the image memory 3 in the lookup table 9 as shown in FIG.
The image memory 2 and the image memory 3 serially output the drawn image data pixel by pixel in the form shown in FIG.
The transparency detection unit 7 detects a transparency signal in which each bit of RGBI is 0 output from the image memory 2 and the image memory 3, and outputs a switching signal. The data selector 11 switches the image data output from the image memory 2 and the image data output from the image memory 3 according to the switching signal.

When the switched 4-bit image data is input to the lower address 4 bits of the lookup table 9 and the switching signal is input to the 5th bit of the highest address, when the transparent signal is 1, that is, the image memory 2 is transparent. 6, the luminance / color difference data for the image memory 3 at the addresses 10h to 1Fh in FIG.
The luminance / color difference data for the image memory 2 of ˜0 Fh is output from the lookup table 9. As described above, the image data in the image memory 2 and the image data in the image memory 3 are overlapped, and at the same time, bit expansion from 4 bits to 2 bits and RG are performed.
The BI data is converted into luminance / color difference data Y, RY, BY. The arithmetic circuit 10 is a lookup table 9
The data output in the form of FIG. 2 is calculated and output in a form in which the color difference data is represented as the average value of the adjacent pixels as shown in FIG.

Next, the operation of the video system will be described.
The NTSC-luminance / color difference decoder 4 decodes the NTSC signal into analog luminance / color difference data Y, RY, BY, and the A / D converter 5 converts the analog luminance / color difference data into the luminance band of the color difference data C. Utilizing the fact that it is narrower than the data Y and the sampling frequency can be half, it is converted into the digital luminance / color difference data of the form shown in FIG. The parallel-serial conversion circuit 6 multiplexes the color difference data and outputs it in the form of the color difference data C shown in FIG.

The video data and the digital graphics data output from the arithmetic circuit 10 are output when both the data in the image memory 2 and the data in the image memory 3 detected by the transparency detector 7 are transparent. The data selector 11 switches according to the switching signal. The frame memory control unit 12 stores the digital still image data for one screen superimposed in this way in the frame memory unit 10.
The data of Y and C are separately stored in the designated storage area 3 of FIG.

The frame memory control unit 12 calls the digital still image data for one screen in the designated area from the frame memory unit 103 in the same form as in FIG.
The serial-parallel conversion circuit 13 separates the digital still image data in the form of FIG. 5 into the form shown in FIG. D /
The A converter 14 converts the digital still image data into analog still image data, converts it into an NTSC signal by the luminance / color difference-NTSC encoder 15, and outputs it. Further, the digital luminance data Y and the digital color difference data C are output as they are from the frame memory unit 103 in the form of FIG.

Example 2. In the first embodiment, an example in which 4-bit image data per pixel is drawn in the image memories 2 and 3 has been described. However, the number of bits per pixel is 6 bits,
Any number such as 8 bits is acceptable.

Example 3. Although the lookup table 9 for expanding the image data of 4 bits per pixel to the image data of 24 bits is used in the first embodiment, the number of output bits of the lookup table 9 is changed to 2
It can be extended to more than 4 bits.

[0036]

As described above, according to the first aspect of the present invention, the digital graphics data and the digital video data are generated, the two data are superposed in the form of the luminance / color difference data, and then the frame memory is used. Since it is configured to be stored in the unit, there is an effect that still image data without deterioration can be stored and the frame memory can be reduced.

According to the second aspect of the present invention, since the graphics data is converted into the data having the same form as the video data before the superimposition is performed, the superimposition can be easily performed and the frame memory can be reduced. effective.

According to the third aspect of the present invention, since the still image output section for simultaneously outputting the still image data and the original television signal is provided, the still image data without deterioration can be obtained and the television can be obtained. This has the effect of monitoring the signal.

According to the fourth aspect of the invention, since the lookup table for converting the graphics data composed of the primary color / luminance data into the luminance / color difference graphics data is used, the graphics as the primary color / luminance data is This has the effect of eliminating the need for a conversion circuit for converting data to luminance / color difference graphics data.

According to the fifth aspect of the invention, the transparent portion of the graphic data is detected, and the graphics data and the video data are switched based on the detection so that the superimposition is performed. This has the effect of reducing the number of tables.

[Brief description of drawings]

FIG. 1 is a block diagram showing a still image storage device according to an embodiment of the present invention.

FIG. 2 is a timing chart showing the form of digital graphics data output from the look-up table in FIG.

3 is a timing chart showing a form of digital graphics data output from the arithmetic circuit in FIG.

4 is a timing chart showing forms of video data output from the A / D converter and digital still image data input to the D / A converter in FIG. 1. FIG.

5 is a timing chart showing forms of video data input to the overlay control unit and digital still image data output from the frame memory control unit in FIG. 1. FIG.

6 is a timing chart showing a form of data stored in a lookup table in FIG.

FIG. 7 is a block diagram showing a conventional still image storage device.

8 is a form of video data output from the A / D converter in FIG. 7 and digital still image data output from the frame memory control unit, and digital graphics data expanded by the lookup table in FIG. 2 is a timing chart showing the form of video data.

FIG. 9 is a block diagram showing a conventional image superposing device.

10 is a timing chart showing a form of digital graphics data in FIGS. 1 and 9. FIG.

11 is a timing chart showing a form of data stored in the lookup table in FIG.

[Explanation of symbols]

 7 Transparency Detection Unit 9 Lookup Table 100 Graphics Data Generation Unit 101 Video Data Generation Unit 102 Overlay Control Unit 103 Frame Memory Unit 104 Still Image Output Unit

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[Procedure amendment]

[Submission date] August 16, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction content]

[0007]

Since the conventional still picture storage device is constructed as described above, since the still picture is stored as RGB digital still picture video data, the frame memory 23 is used. The number of In addition, when digital graphics data such as characters is to be superimposed on a video still image, an image superimposing device as shown in FIG. 9 is required outside the still image storage device. Further, when performing image superposition control, it is necessary to re-decode the still image output from the still image storage device as an NTSC signal, perform A / D conversion into digital still image data, and then perform superimposition. eyes, the image quality of the still image there is a problem such as a deteriorated.

Claims (5)

[Claims] 1. A graphics data generation unit for generating a plurality of digital graphics data in response to an external drawing control command, a video data generation unit for decoding a television signal to generate video data, and the graphic. Of the digital graphics data generated by the video data generation unit and the video data generated by the video data generation unit and output as luminance / color difference data, and the luminance obtained from the superposition control unit. A still image storage device including a frame memory unit that stores color difference data as still image data. 2. A graphics data generation unit for generating a plurality of digital graphics data in response to an external drawing control command, a video data generation unit for decoding a television signal to generate video data, and the graphic. Digital graphics data generated by the video data generation unit is converted into the same data form as the video data, and the converted data and the video data generated by the video data generation unit are superimposed and output as luminance / color difference data. A still image storage device comprising: an overlay control unit; and a frame memory unit that stores the luminance / color difference data obtained from the overlay control unit as still image data. 3. A graphics data generation unit for generating a plurality of digital graphics data in response to an external drawing control command, a video data generation unit for decoding a television signal to generate video data, and the graphic. Of the digital graphics data generated by the video data generation unit and the video data generated by the video data generation unit and output as luminance / color difference data, and the luminance obtained from the superposition control unit. A frame memory unit that stores color difference data as still image data, and outputs the still image data read from the frame memory unit,
A still image storage device including a still image output unit that outputs an original television signal restored from the still image data. 4. A graphics data generation unit for generating a plurality of digital graphics data each consisting of primary color / luminance data in response to a drawing control command from the outside, and a luminance / color difference data obtained by decoding a television signal. A video data generation unit for generating video data, a look-up table for converting the digital graphics data generated by the graphics data generation unit into graphics data composed of luminance / color difference data, and the look-up table A superimposition control unit that superimposes graphics data and video data generated by the video data generation unit as luminance / color difference data, and the brightness / color difference data obtained from the superposition control unit as still image data. Frame memory section to store Still image storage device having. 5. A graphics data generation unit for generating a plurality of digital graphics data each composed of primary color / luminance data in response to an external drawing control command, and a luminance / color difference data obtained by decoding a television signal. The video data generation unit that generates video data, the transparency detection unit that detects a transparent portion of the digital graphics data generated by the graphics data generation unit, and the brightness of the digital graphics data generated by the graphics data generation unit. Switching between the look-up table for converting to the graphics data composed of color difference data, the graphics data converted by the look-up table, and the video data generated by the video data generation unit based on the detection of the transparency detection unit Both de Still image storage device including a superposition control unit that superimposes the data and outputs it as luminance / color difference data, and a frame memory unit that stores the luminance / color difference data obtained from the superposition control unit as still image data. .