JP3162231B2 - Digital image display system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital image display system comprising a digital data output device such as a computer and a display device for displaying an image transmitted from the digital data output device. .

[0002]

2. Description of the Related Art At present, most display devices used in computer terminals and the like use analog RGB video signals as an interface for input video signals, and display resolution tends to be high in recent high definition displays. , The horizontal deflection frequency is 90 kHz, and the video signal band is about 150 MHz. For this reason, there are problems such as a loss when transmitting a video signal to a display device distant from the computer main body and generation of unnecessary radiation noise.

[0003] In order to solve the above-mentioned problem, the computer main body transmits the low-frequency digital video data to a display device without converting the video signal into an analog signal.

[0004] As a prior art of this type of display device, for example, the one described in JP-A-61-233779 can be mentioned. Here, the digital video data read from the image memory of the computer main body is output to the display device as a parallel signal as it is, and the display device performs digital-to-analog conversion and returns to an analog video signal to display the video. .

[0005]

In the above conventional example, for example, one screen is 640 × 480 (horizontal 6 pixels) at a standard display resolution used in a normal personal computer class.
When each of the RGB video signals has 8-bit gradation (that is, 16.67 million colors can be displayed per one dot of the above resolution) in the case of 40 dots and 480 vertical dots, the digital video data is The amount of data transfer required for transfer to the display device side reaches about 55 Mbytes / sec. Furthermore, one screen is one screen with the high definition display resolution used in the workstation class.
Approximately 280 × 1024 dots, and a transfer amount of about 80 Mbytes / sec is required even when the display color per dot is 256 colors. At present, this resolution is in the direction of further improvement, and the display color is also approaching 16.67 million colors that enable natural images to be displayed on a display device.

As described above, when an image to be displayed on a display device is transmitted as digital image data from the computer main body, the amount of data to be transmitted is enormous. Therefore, in the above conventional example, when digital video data is transmitted in 8-bit parallel, a transfer clock frequency of about 55 MHz is simply required for the standard display resolution and about 80 MHz for a high definition display resolution. As a result, as a result, the effect of reducing the unnecessary radiation is not so obtained. Further, it is practically difficult to realize such high-speed data transfer while maintaining the reliability without the influence of bit omission or noise. Furthermore,
If the data width to be transmitted is increased from 8 bits to doubled 16 bits and doubled 32 bits, the frequency of the transfer clock can be reduced, but the number of lines of the digital video data transfer cable increases and the routing becomes extremely large. This is inconvenient, and it is not practical to increase the distance between the computer body and the display device.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a digital image display system which requires a small amount of data to be transmitted when transmitting an image from a computer or the like to a display device. Another object of the present invention is to further improve the functions of the display device by digital signal processing.

[0008]

In order to solve the above-mentioned problems, a computer body is newly provided with an interface means, and an interface means for receiving a drawing command signal , a drawing processing means, a video memory means, and a video memory on the display device side. Digital-to-analog conversion means is newly provided.

Further, the display device further includes voice processing means, voice memory means, voice digital / analog conversion means, speaker, microphone, and voice analog / digital conversion means.

Alternatively, the display device includes pre-processing means, clock generation means, video analog-to-digital conversion means and digital interface means, drawing processing means different from the above, switching control means, video memory means, and video digital / digital conversion means. Analog conversion means is newly provided.

Alternatively, the display device includes a digital interface unit, a switching control unit, another drawing processing unit, a video memory unit, and a video digital
An analog conversion unit, another analog video signal input unit, and a video switching unit are newly provided.

Further, the display device is further provided with sensor means, A / D conversion means, arithmetic control means, and characteristic memory means for storing characteristic data.

Alternatively, the computer side is provided with drawing processing means, compression processing means and digital interface means, and the display device side is newly provided with digital interface means, decompression processing means, memory means and video digital / analog conversion means. .

Alternatively, the computer main body is provided with drawing processing means, video memory means, compression processing means and digital interface means, and the display device side is provided with digital interface means, decompression processing means and video digital / analog conversion means. Newly provided.

Alternatively, an input device interface means for an input device is further provided on the display device side. Also on
In order to solve the above problem, a display device of the present invention
Can be connected to a digital data output device,
Digital video output from a digital data output device
A drawing command is input, and the digital video drawing data is
Create analog video drawing data and synchronization signal based on
Conversion processing means, and the analog video drawing data
Video processing means, and a deflection for inputting the synchronization signal.
Processing means, the video processing means and the deflection processing means,
Display means for displaying video by the control of
Configuration. In order to solve the above problems, the present invention
The display device outputs a digital image drawing command.
Digital data communication with digital data output devices
Digital interface means for enabling
Digital video input to digital interface means
Synchronize digital video data and synchronization signal based on drawing command
Drawing processing means for creating, and the digital video data
Digital / analog converting to analog video drawing data
Conversion means, the analog video drawing data and a synchronization signal
And display means for displaying video based on the
And

[0016]

Each of the above means operates as follows. The digital interface means between the computer and the display device outputs a drawing command and a voice command signal of the display device to the display side, and exchanges information such as a control command, an operation state, a voice file, and display characteristic data from the display device side. . The drawing processing means creates video data for displaying a video from the drawing command. The video memory means holds the video data created by the drawing processing means for one screen. The video digital / analog converter converts the video data read from the video memory into an analog video signal.

The voice processing means creates voice data from a voice command signal sent from the digital interface means, and conversely sends the voice data to the digital interface means as a voice command or a voice file.
The voice memory means temporarily holds the voice data created by the voice processing means. The audio digital / analog conversion means converts the audio data into an audio signal and generates sound from a speaker. The voice analog / digital conversion means converts the sound taken from the microphone into voice data.

Further, the pre-processing means performs a clamping process of an analog video signal input to the display device, extracts a synchronizing signal, and the like. The clock generating means generates a sampling clock phase-synchronized with the synchronizing signal, and The digital conversion means digitizes the video signal according to the sampling clock. Further, another drawing processing means creates video data from the drawing command signal, and appropriately switches between the video data and the digitized video signal or performs an imposition process. The switching control means instructs such switching of the video processing mode by another drawing processing means.

Still another drawing processing means creates video data of various resolutions, and the video switching means has two types of video signals, namely, a video signal from an analog video signal input means and a video signal based on the video data generated by the drawing processing means. Switch the video signal. At this time, the switching control means controls the definition of the video data created by the drawing processing means, and also controls the video switching means via the drawing processing means.

The sensor means detects the display characteristics of the display device, the A / D conversion means digitizes the posted value, the arithmetic control means calculates and generates the digital value as the characteristic data of the display device, Control. Further, the characteristic memory means holds characteristic data.

The compression processing means performs information compression processing on the video data created by the drawing processing means to reduce the amount of information. The decompression processing means reproduces the compressed video data into the original information.

Further, the input device interface means takes in a control command from an input device such as a keyboard, a mouse, a touch panel, and a pen input tablet into a display device and converts it into a format which can be transmitted to the computer main body by the digital interface means.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a reference example useful for understanding the present invention . In the figure, a portion 1A surrounded by a dashed line is a computer main body.
Is a bus for data, address, and control signals;
1 is an arithmetic control circuit (hereinafter referred to as a CPU), 12 is a main memory, 13 is an input / output port for connecting a computer external device such as a printer or a modem to the computer main unit 1A, and 14 is an external storage device 3 described later. An external storage device interface for transferring data, 15 is an input device interface for inputting a control command from an input device 4 described later, and 16 is a video drawing command transmitted as digital data through the bus 10 A digital data interface (hereinafter, referred to as a digital I / F) for transmission to a display device.

A portion 2A surrounded by another dashed line is a display device, in which 21 is a digital I / F for receiving a video drawing command transmitted as digital data from the computer main body 1A. 22
Is a drawing processing circuit for creating digital image data for displaying an image from the image drawing command received by the digital I / F 21, and 23 is an image memory (hereinafter, referred to as an image memory for holding the digital image data created by the drawing processing circuit 22). , VRAM), 24 is a look-up table (hereinafter, LUT), 25 is a digital-to-analog converter (hereinafter, DAC), 26 is a video circuit, 27 is a deflection circuit, and 28 is a color display tube (hereinafter, CDT). ).

Reference numeral 3 denotes an external storage device using a storage medium other than the main memory 12, such as a floppy disk, hard disk, magneto-optical disk, or magnetic tape, and 4 denotes a keyboard, a mouse, a pen input tablet, or a touch panel. Input devices 5 are digital I / Fs 16 and 21
CD that handles digital video data that can be connected to
It is a digital video media device such as a ROM, a magneto-optical disk recording / reproducing device, a scanner, an electronic still camera, a digital VTR, and a camera-integrated VTR (generally called a movie) capable of handling digital video data.

The operation of FIG. 1 is as follows. The computer main body 1A is a computer main body having the same configuration as a general personal computer or a workstation, but is usually connected to the bus 10 and has analog RGB components.
A digital I / F 16 is connected instead of a video graphic circuit for creating a video signal. Then, when a control command is read from the input device 4 such as a keyboard or the external storage device 3 such as a floppy disk drive, the control command is taken into the CPU 11 via the external storage device interface 14 or the input device interface 15. In response to the control command, the CPU 11 issues a video drawing command. The image drawing command is transmitted as digital data to the display device 2A via the digital I / F 16.

On the other hand, the display device 2A receives the transmitted video rendering command via the digital I / F 21, and the rendering processing circuit 22 interprets the received video rendering command to create digital video data. , A synchronization signal (Hs,
Vs) also occurs. The created digital video data is sequentially stored in the VRAM 23 and then read out for video display. Therefore, the VRAM 23 used here is a two-port memory type having separate input / output ports. The LUT 24 stores a conversion table for converting digital video data read from the VRAM 23 into digital video data having color signal amplitude information to be actually displayed. Digital video data with signal amplitude information is DAC
25. The DAC 25 converts the digital video data into an analog RGB video signal and converts the digital video data into an input video signal form of a general display device. In addition, LUT
The contents of the conversion table stored in 24 can be rewritten by a rewriting signal from the drawing processing circuit 22, and the color displayed on the screen of the CDT 28 can be freely changed. Further, the LUT 24 can be omitted. In this case, the contents of the VRAM 23 correspond one-to-one to the signal amplitude information of each of the RGB colors. The converted analog RGB video signal is input to the CDT 28 via the video circuit 26, and the synchronizing signal generated by the drawing processing circuit 22 is also input to the CDT 28 via the deflection circuit 27, and is used for a general display device. Similar image display is performed.

As described above, in the present embodiment , the image to be displayed from the computer main unit 1A is transmitted to the display device 2A as an analog image signal or digital image data obtained by digitally converting the analog image signal, as in the related art. Instead, the data is transmitted to the display device 2A as a video rendering command, which is digital data, to reduce the amount of data to be transmitted.

Here, how the amount of data to be transmitted differs between the case where the image to be displayed is transmitted as an image drawing command and the case where the image to be displayed is transmitted as digital image data will be described with reference to FIG.

FIG. 2 is an explanatory diagram showing a comparison between a case where a video to be displayed is transmitted as a video drawing command and a case where it is transmitted as digital video data.

For example, the display resolution of the display device 2A is 640 × 480 per screen (640 dots horizontally, 4 dots vertically).
(80 lines) dots,
Consider the case where a line is displayed on the first line.
As shown in FIG. 2A, when this video is transmitted as a video rendering command, "LINE (0,0)-(0,640)" which is a command (command) for displaying a line on the first line. Is transmitted from the computer main body 1A to the display device 2A as digital data, and digital video data for displaying a video is created inside the display device 2A and displayed on the screen. Therefore, basically, it is only necessary to transmit a simple video drawing command “LINE (0,0)-(0,640)” in the form of digital data from the computer main body 1A to the display device 2A. The data volume is small.

On the other hand, as shown in FIG.
In the case of transmission as digital video data, data "11111 ... 111111" representing a line on the top line, that is, "1" as data for one line corresponding to the top line (indicating that screen display is performed) Data) to 640
After the data is transmitted from the computer main body 1A to the display device 2A, data for the remaining number of lines (479 lines) is transmitted and displayed on the screen in the display device 2A as it is. That is, when transmitting as digital video data, the data to be transmitted has a one-to-one correspondence with the display screen.
Needs to transmit 640 × 480 data to the display device 2A, and the amount of data to be transmitted becomes very large.

As described above, in the present embodiment , when an image to be displayed on the display device is transmitted from the computer main body, the amount of data to be transmitted can be reduced by transmitting the image as an image drawing command. Therefore, the signal frequency in the transmission path is reduced, unnecessary radiation can be reduced, and there is no need to worry about the effects of bit omission and noise, and it is not necessary to increase the number of cables.

Although the digital I / Fs 16 and 21 can use their own interfaces,
By using a general-purpose parallel interface such as a CSI interface or a printer interface, or a general-purpose serial interface such as a network interface, applications can be expanded. That is, for example, SCS
When the I interface is used, a multimedia image device such as a CD-ROM or an image capturing device such as a scanner is connected as the digital image media device 5 to the interface portion, and the digital image data sent from the device 5 is displayed. It can also be taken into the device 2A and directly displayed on the display device 2A.
In this case, the drawing processing circuit 2 inside the display device 2A
2 communicates with the digital video media device 5 via the digital I / F 21 and determines what type of digital video media device 5 is connected. It has an intelligent processing function that can be used.

Therefore, in the present embodiment , the video can be displayed on the screen of the display device 2A without the help of the computer main unit 1A by directly connecting the digital video media device 5 capable of reproducing various video media. .

In this embodiment , the digital I / F 1
6 and 21 are connected by a bidirectional bus, so that the drawing processing circuit 22 and the VR
The operating states of the AM 23, the LUT 24, and the like are detected, and the detection results can be transmitted as commands to the computer main unit 1A via the digital I / Fs 16 and 21.
When such transmission is performed, the operation can be checked when the power is turned on or at the time of factory adjustment.

FIG. 3 is a block diagram showing another embodiment of the present invention . In the figure, a portion 2B surrounded by a dashed line is a display device, in which 29 is an audio processing circuit, 210 is an audio memory circuit, 211 is a DAC for converting digital audio data into analog audio, 21
Reference numeral 2 denotes a speaker, 213 denotes an analog / digital converter (hereinafter, referred to as ADC), and 214 denotes a microphone. The same reference numerals as those in FIG. 1 denote the same components as those in FIG.

The operation of FIG. 3 will be described below. Ginseng
In the example , as shown in FIG. 3, a video rendering instruction and an audio processing instruction are transmitted as digital data from the computer main unit 1A or the digital video media device 5 shown in FIG. Will be. The transmitted digital data is received via a digital I / F 21, and from the image rendering command, a circuit composed of a rendering processing circuit 22, a VRAM 23, an LUT 24, a DAC 25, and the like, like the display device 2A of FIG. An analog video signal is obtained. The voice processing command is demodulated by the voice processing circuit 29 with an actual voice image, and converted into digital voice data in the voice memory 210.
, And is converted to an analog audio signal by the D / A converter 211. This audio signal is output as an audio through the speaker 212.

As described above, in the present embodiment , video and audio can be transmitted as the video rendering command and the audio processing command using the same interface, and the need for additional lines is eliminated. Furthermore, when application software that handles video and audio is operated on the computer main unit 1A side, by connecting the display device 2B of this embodiment , video display and audio can be easily performed without the need for other additional circuits. The output is obtained.

In this embodiment , the voice is fetched from the microphone 214, converted into digital voice data by the A / D converter 213, modulated by the voice processing circuit 29, and then transmitted via the digital I / F 21 to the computer main body. 1A and can be utilized as audio data. Note that a speaker 2 is used instead of the microphone 214 as a voice input device.
12 can also be used. In this case, as shown by the dotted line in FIG.
It is input to a transform 213 and processed as described above.

Based on the above, FIG. 4 is a block diagram showing an embodiment of the present invention . In the figure, a portion 2C surrounded by a dashed line is a display device.
Reference numeral 33 denotes a drawing processing circuit different from the drawing processing circuit 22 shown in FIGS. 1 and 3, reference numeral 34 denotes a preprocessing circuit, reference numeral 35 denotes an ADC, reference numeral 36 denotes a buffer circuit, reference numeral 37 denotes a PLL circuit, reference numeral 38 denotes a signal switching circuit. 1 and 3 denote the same components.

The operation of FIG. 4 will be described below. In this embodiment, as shown in FIG. 4, an image rendering command is transmitted as digital data from the computer main unit 1A shown in FIG. 1 to the display device 2C, and a general computer main unit, VTR, LD player, etc. An analog video signal (hereinafter, referred to as a video signal) is transmitted from the video output device. The video drawing command transmitted as digital data is received via the digital I / F 21, and the drawing processing circuit 22 creates digital video data based on the video drawing command.

On the other hand, the transmitted video signal is input to the pre-processing circuit 34, where the video signal is subjected to a video clamping process and, if the video signal is a composite type, a process of extracting a synchronization signal from the video signal. The video signal subjected to these processes is converted by the ADC 35 into digital video data. Here, the sampling clock used for the ADC 35 is created by a PLL circuit 37 including a general phase lock circuit in order to synchronize with a synchronization signal output from the preprocessing circuit 34. The digital video data obtained by the conversion is sequentially read into the drawing processing circuit 33 via the buffer circuit 36.

The switching control circuit 38 is provided with an instruction from the user outside the display device 2C as to what kind of video processing is to be performed, and the digital I / F 21 and the drawing processing circuit 33 from the computer main unit 1A. , A switching control command is given. The switching control circuit 38 interprets the given instructions and commands and gives predetermined instructions to the drawing processing circuit 33. In accordance with an instruction from the switching control circuit 38, the drawing processing circuit 33 switches and outputs digital video data created based on a video drawing command and digital video data obtained by converting a video signal, and Image processing. As a display form obtained by the switching or the video processing, when either the video based on the video drawing command or the video based on the video signal is displayed on the CDT 28, one of them is displayed on the screen of the CDT 28, There is a case where the other is displayed in a window at an appropriate place, a case where the other is superimposed on one of the displayed images, or a case where the image is enlarged, reduced or scrolled in each of the above cases. . The digital video data that has been switched or subjected to video processing by the drawing processing circuit 33 is then written to the VRAM 23. Subsequent circuit operations are the same as in FIG.

Therefore, in this embodiment, not only the video signal is transmitted to the display device 2C but also a normal video signal, so that any one of those video images can be displayed on the screen. Different types of images can be displayed simultaneously in various display modes.

FIG. 5 is a block diagram showing another embodiment of the present invention . In the figure, a portion 2D surrounded by a dashed line is a display device, in which 41 is a drawing processing circuit different from the drawing processing circuit 22 in FIGS. 1 and 4, and 42 is an analog signal switching circuit (hereinafter, referred to as an analog signal switching circuit). SW)
The same reference numerals as in FIGS. 1, 3, and 4 denote the same components.

The operation of FIG. 5 is as follows. In the present embodiment, as shown in FIG. 5, the display device 2D includes:
As in FIG. 4, a video rendering command is transmitted as digital data from the computer main unit 1A shown in FIG. 1, and a video signal is transmitted from a general computer main unit or a video output device such as a VTR or an LD player. .
In the processing inside the display device 2D, the video signal is directly input to the SW 42, and no digital processing is performed. On the other hand, the video drawing command is generated by the drawing processing circuit 41, VR
The signals are converted into analog video signals by the respective circuits of the AM 23, the LUT 24, and the DAC 25, and are input to the SW 42.

Here, the drawing processing circuit 41 responds to an instruction from the switching control circuit 38 similar to that shown in FIG.
And determining whether to select the image based on the image drawing command or the image based on the video signal as the image to be displayed in step S8.
W42 is controlled. The control method is as follows.

In the first display control mode, one of the video based on the video drawing command transmitted to the display device 2D and the video based on the video signal is displayed on the CDT 28. At this time, if an image based on the video signal is selected, the synchronizing signals Hs and Vs input to the display device 2D accompanying the video signal are once input to the drawing processing circuit 41 and directly provided to the deflection circuit 27. . Therefore, the synchronization signals Hs and Vs are equal to the synchronization signals Hs 'and Vs' output from the drawing processing circuit 41. Conversely, when an image based on the image drawing command is selected, the synchronization signal H
s 'and Vs' are asynchronous with the synchronization signals Hs and Vs and are generated at a period suitable for display.

Next, in the second display control mode, while displaying an image based on the video signal, the image based on the image drawing command is window-displayed. At this time, the input / output synchronization signal of the drawing processing circuit 41 is the same. Here, if the display resolution of the video based on the video signal is sufficiently higher than the display resolution of the video based on the video rendering command, the rendering control circuit 4
In step 1, digital video data is created based on a video rendering command in synchronization with the synchronization signals Hs and Vs. Thereafter, all digital video data is read from the VRAM 23 at a predetermined timing, and is converted into an analog signal by the LUT 24 and the DAC 25. The analog video signal is switched with the video signal at a predetermined timing in the SW 42, and the video based on the video drawing command is window-displayed in the display area of the video based on the video signal.

This situation is shown in the timing chart of FIG. The display period of the video signal is the T1 period in FIG. 6 with respect to the horizontal synchronization signal Hs of the video signal, and the drawing processing circuit 41
Selects the analog video signal output from the DAC 25 in the T2 period shorter than the T1 period, and selects the video signal in other periods. As a result, the output from the SW 42 is switched as shown in FIG. 6, and a window can be displayed in the horizontal direction. When the read start time of the digital video data read from the VRAM 23 with respect to the horizontal synchronization signal Hs is shifted in accordance with an instruction from the switching control circuit 38, the window display position is controlled by a control signal S issued from the drawing processing circuit 41.
1 also moves as shown by the dotted line in FIG. 6, and the window display position can be changed. The same can be done in the vertical direction.

Next, when the display resolution of the video based on the video signal is equal to or lower than the display resolution of the video based on the video rendering command, the following processing is performed. FIG. 7 shows a timing chart in this case. Drawing processing circuit 41
Therefore, if the digital video data held in the VRAM 23 is adjusted to the synchronization signal Hs and all the data is read as it is, the video signal exceeds one horizontal period of the synchronization signal Hs as in the output of the unprocessed DAC 25 shown in FIG. Will be. Therefore, the video processing circuit 41 generates the control signal S1 so that the video data held in the VRAM 23 is decimated and read out, and the video signal is sufficiently contained within the horizontal period as in the post-processing DAC output shown in FIG. SW42 is controlled. Similarly, processing is performed in the vertical direction.

In this way, the display device 2 shown in FIG.
In D, two video signals can be switched and a window can be freely displayed on the screen of the CDT 28.

FIG. 8 is a block diagram showing another embodiment of the present invention . In the figure, a portion 2E surrounded by a chain line
Denotes a display device, in which 71 is a drawing processing circuit different from the drawing processing circuit in each of the above drawings, 72 is a writable read memory (hereinafter referred to as ROM), 7
Reference numeral 3 denotes a CPU, 74 denotes an ADC, 75 denotes a light receiving device such as a sensor or a camera, and the same reference numerals as those in FIG. 1 denote the same components.

Hereinafter, the operation of FIG. 8 will be described. FIG.
1 , the drawing process is performed in exactly the same manner as in the reference example of FIG. 1. A video drawing command is transmitted from the computer main unit 1 </ b> A shown in FIG. 1 to the display device 2 </ b> E and received via the digital I / F 21. From the image drawing command, the drawing processing circuit 71, VRAM 23, LUT 24, DA
An analog video signal can be obtained by a circuit including C25 and the like.

On the other hand, the ROM 72, the CPU 73, the ADC 7
4. The portion composed of the light receiving device 75 measures and processes various characteristics related to the display of the display device 2E, and holds the obtained data. Here, the characteristics to be measured include:
The so-called gamma characteristics, the highest luminance, the lowest luminance, the color temperature, and the like of the CDT 28 are listed. As a method of measuring characteristics,
The CPU 73 controls the drawing processing circuit 71 to cause the CDT 28 to display an all-white screen, a single-color RGB screen, an intermediate luminance screen, a low luminance screen, and the like. At this time, the light receiving device 75 measures the state of the CDT 28 on the tube surface. . The measurement result is digitized by the ADC 74 and input to the CPU 73. CPU73
Performs a predetermined calculation based on the level of the analog video signal output from the DAC 25 and the measurement result, and uses the result as display characteristic data of the display device 2E in the ROM 7.
Write to 2. The data written in this way is transmitted to the computer main unit 1A via the digital I / F 21 when there is a request from the computer main unit 1A or when the power of the display device 2E is turned on. The transmitted characteristic data is read into the computer main body 1A, and is used for so-called color matching, for example, for matching the color of an image displayed on the display device 2E with the color of a printed matter when the color is output to a printer or the like. Correction instruction data for correcting the deviation from the printed matter at this time by the display device 2E is sent from the computer main body 1A to the display device 2E, and the drawing processing circuit 71 and the CPU 73 correct the analog video signal to be output to the DAC 25. Thus, it is possible to display an image in a color matching the printed matter.

FIG. 9 is a block diagram showing a reference example of the present invention . In the figure, a portion 1B surrounded by a dashed line is a computer main body, in which 81 is a drawing processing circuit, 82 is a compression circuit, and a portion 2F surrounded by another dashed line is a display device. Among them, 83 is a decompression circuit. The same reference numerals as those in FIG. 1 denote the same components.

The operation of FIG. 9 is as follows. CPU 11, main memory 12, I / O port 13, external storage device I / F 14, input device I / F 15 in the computer main body 1 B
Each of the circuit portions functions similarly to a general computer. Various control commands and digital video data input to the CPU 11 from the external storage device 3 and the input device 15 via the bus 10 are processed by the CPU 11. It is processed and sends a control command relating to video generation to the drawing processing circuit 81. The drawing processing circuit 81 develops this control command into digital video data for actually displaying a video. Here, the amount of information of this digital video data is a huge amount of information of about several hundred megabytes per second, and the data is compressed by the compression circuit 82 to about tens to hundreds of tens. To make the level transferable by the digital I / F 16.
The digital video data subjected to the compression processing is a digital I / O
It is output from F16 to the display device 2F.
In addition to the digital video data, the drawing processing circuit 81 also generates synchronizing signal information of the display device 2F and display control data for controlling the display state, and is output from the digital I / F 16 to the display device 2F together with the digital video data. You.

In the display device 2F, the digital I
The digital video data and the display control data compressed by / F21 are received and passed to the decompression circuit 83 at the next stage. The decompression circuit 83 decompresses the compressed digital video data, reproduces it as the original digital video data, and writes it into the VRAM 23. The expansion circuit 8
3 is the display device 2 from the display control data.
The horizontal and vertical synchronizing signals (Hs, Vs) necessary for driving the F deflection circuit 27 are generated, and the setting value of the LUT 24 is rewritten to change the display color of the display image and the image signal level. . As described above, after the digital video data is stored in the VRAM 23, the LUT 24 and the DA
An analog video signal is extracted by each process of C25, passes through the video circuit 26, and is displayed on the CDT 28 by driving the CDT 28. In the present embodiment , digital video data is compressed on the transmission side and decompressed on the reception side, so that digital digital video data can be transmitted in a system based on general interface specifications.

In this embodiment , as in the case shown in FIG. 5, a switching control circuit 38, an analog signal switching circuit 42 and the like are provided. by controlling the analog signal switching circuit 42, it is possible to obtain the same effect as the embodiment of FIG. 5, an embodiment of the present invention configured
To achieve.

FIG. 10 is a block diagram showing still another embodiment of the present invention . In the figure, a portion 1C surrounded by a dashed line is a computer main body.
1 is a VRAM for storing digital video data,
Reference numeral 92 denotes a compression circuit, and the same reference numerals as those in FIGS. 1 and 9 denote the same components. A portion 2G surrounded by a dashed line is a display device, in which 93 is a decompression circuit, and other components that are the same as those in FIG. 1 are the same components.

In the present embodiment, as shown in FIG.
The control command relating to the video generation created by the PU 11 is sent to the drawing processing circuit 81 to create digital video data. The digital video data created by the drawing processing circuit 81 is temporarily stored in the VRAM 91, and is stored in the compression circuit 9 in the next stage.
2 reads the stored digital video data. The compression circuit 92 compresses the read digital video data and sets the data amount to an information amount that can be transmitted by the digital I / F 16. Further, from the drawing processing circuit 81, control data relating to display on the display device 2G, such as synchronization signal information and display colors, is output.
Sent to Accordingly, the digital I / F 16 compresses the digital video data and the display device 2G.
Is output.

In the display device 2G, the digital I
The data is sequentially sent to the decompression circuit 93 via / F21. The decompression circuit 93 expands the compressed digital video data, sequentially returns to the original digital video data format, and outputs the analog video signal to the video circuit 26 by the LUT 24 and the DAC 25. The expansion circuit 93
Is a synchronizing signal (Hs, Vs) to be given to the deflection circuit 27 from the control data of the display device, and the LUT 24
Create the set value change data for. As above,
A large amount of digital video data can be transmitted on a line based on a general interface specification, so that image quality deterioration and unnecessary radiation on the transmission line can be suppressed.

In this embodiment, as in the case shown in FIG. 5, a switching control circuit 38, an analog signal switching circuit 42, and the like are provided. By controlling the analog signal switching circuit 42, an effect similar to that of the embodiment of FIG. 5 can be obtained.

FIG. 11 is a block diagram showing still another embodiment of the present invention . In the figure, a portion 2H surrounded by a dashed line indicates a display device, in which 10H is shown.
1 is an input device interface circuit (hereinafter, input device I /
F) and 102 are input devices, and the same reference numerals as those in FIG. 1 have the same functions.

The operation of FIG. 11 will be described below. In this embodiment, a computer main body 1A as shown in FIG. 1 and a display device 2H are connected, and digital digital video data sent from the computer main body 1A is a digital I / F 21, a drawing processing circuit 22, a VRAM
1, an analog video signal is generated by the LUT 24 and the DAC 25 in the same manner as in FIG. 1, and an image is displayed on the CDT 28 by the video circuit 26 and the deflection circuit 27. Further, input devices such as a keyboard, a mouse, a touch panel, and a pen tablet are connected to the display device 2H shown in FIG. 11, and the input device I / F 101 is connected to the input device 102.
Capture information from. The input device I / F 101 converts the fetched information into a predetermined format and converts the information into a digital I / F.
The control command is sent as a control command to the computer main unit 1A via the control unit 21. The computer main unit 1A processes the control command and creates information to be displayed on the display device 2H. The information created in this way is converted into digital video data by the digital I / F 16 of the computer main unit 1A.
And the display device 2H performs a new video display.

As described above, in this embodiment, the display device 2H
By adding input means 102 to the computer main body 1
Even if the installation distance to A is long, information can be input immediately in the vicinity of the display device 2H, and a high-quality video can be displayed without loss of a video signal due to transmission.

FIG. 12 is a block diagram showing another embodiment of the present invention . In the figure, 1A is the computer main body, 2a, 2a
b and 2c are display devices, and IF is a digital interface. The computer main unit 1A is the same as that shown in FIG. 1, and each display device has the same configuration as that shown in FIG. 1, FIG. 3, FIG. 4, FIG. 5, FIG. 8, or FIG. In this embodiment, an image drawing command output from the computer main body 1A to the digital interface IF is input to each of the display devices 2a, 2b, and 2c connected to the digital interface IF, and an image is individually displayed. Here, prior to the video rendering command, when a selection command indicating which display device is to be output is output, the interface circuit of each display device determines this, and the video rendering command transmitted to the corresponding display device next. Is taken in.
In this way, the selection command is transmitted to the digital interface I
When all the display devices 2a, 2b, 2c connected to F are selected, the same image is displayed at the same time. When the selection command selects the display device 2a, only the image display on the display device 2a is switched to a new one. As described above, it is possible to connect a plurality of display devices to the digital interface IF and display images individually or to display all the images simultaneously with the same display content, thereby increasing usability.

[0070]

According to the present invention, information capable of realizing digital video data for displaying a high-resolution video from a computer to a display device using a digital interface generally used based on a standard is provided. Transmission can be performed at a transmission ratio, and it is possible to reduce line loss, influence of noise, unnecessary radiation due to a high frequency component of a signal to be transmitted, and the like, as compared with the case of transmission using a conventional analog video signal. Further, since the computer main body and the display device can be set apart from each other, the installable range is expanded as compared with the conventional system. Further, since the signal is transmitted in the form of a digital signal, an audio signal, display control information, and the like can be transmitted from the computer to the display device side in addition to the video signal on the same line. Conversely, the internal information of the display can be recognized from the display device side to the computer main body side. Further, since the display device performs the drawing processing, it is possible to display an image synthesized with another input image signal, so that further improvement of the function and usability can be easily achieved. As described above, the present invention exerts various effects.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a reference example for understanding the present invention .

FIG. 2 is an explanatory diagram showing a comparison between a case where a video to be displayed is transmitted as a video rendering command and a case where it is transmitted as digital video data.

FIG. 3 is a block diagram showing another reference example of the present invention .

FIG. 4 is a block diagram showing one embodiment of the present invention .

FIG. 5 is a block diagram showing another embodiment of the present invention .

FIG. 6 is a timing chart illustrating the operation of FIG.

FIG. 7 is a timing chart illustrating the operation of FIG.

FIG. 8 is a block diagram showing another embodiment of the present invention .

FIG. 9 is a block diagram showing a reference example of the present invention .

FIG. 10 is a block diagram showing still another embodiment of the present invention .

FIG. 11 is a block diagram showing another embodiment of the present invention .

FIG. 12 is a block diagram showing another embodiment of the present invention .

[Explanation of symbols]

1A, 1B, 1C: computer body, 11: CPU,
16, 21 ... Digital interface circuit, 2A, 2
B, 2C, 2D, 2E, 2F, 2G, 2H ... display device, 22, 41, 71, 81 ... drawing processing circuit, 2
3, 91 ... Digital video data holding memory circuit, 2
4 Look-up table, 25 Digital-to-analog conversion circuit, 29 Audio processing circuit, 210 Audio memory circuit, 101 Second input device interface circuit

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G09G 5/36

Claims (10)

(57) [Claims] 1. An image display system comprising: a digital data output device; and a display device for displaying a video transmitted from the digital data output device, wherein the digital data output device is used for displaying a video. A CPU for creating and outputting a video drawing instruction and a switching control instruction for performing switching control, respectively;
And first digital interface means for transmitting the video drawing command and the switching control command output from the display device to the display device, wherein the display device receives the transmitted video drawing command and the switching control command. A second digital interface unit, a preprocessing unit that performs a clamping process on an analog video signal input from outside separately from the video rendering command and outputs the same, and extracts and outputs a synchronization signal from the analog video signal; A clock generation unit that generates and outputs a clock signal that is phase-synchronized with the synchronization signal from the synchronization signal output from the preprocessing unit, and that uses the clock signal output from the clock generation unit as a sampling clock. Converts the analog video signal output from the preprocessing means into digital video data Means for temporarily holding and outputting digital video data output from the analog / digital conversion means, and a switching control command received by the second digital interface means. A switching control means for outputting a switching instruction based on an instruction relating to video processing input from the outside in addition to the switching control instruction; and a digital image rendering instruction based on a video drawing instruction received by the second digital interface means. Data and a synchronizing signal, respectively, and, according to a switching instruction output from the switching control means, among the digital video data thus generated and the digital video data output from the temporary holding means, one of them is selected. Drawing processing means for outputting, and the drawing Image memory means for temporarily holding digital video data output from the image processing means and outputting the digital video data; digital / analog conversion means for converting the digital video data output from the image memory means into an analog video signal and outputting the analog video signal; A digital image display system, comprising: display means for displaying an image based on an analog video signal output from the digital / analog conversion means and a synchronization signal created by the drawing processing means. 2. An image display system comprising: a digital data output device; and a display device for displaying a video transmitted from the digital data output device, wherein the digital data output device is configured to display a video. A CPU for creating and outputting a video drawing instruction and a switching control instruction for performing switching control, respectively;
And first digital interface means for transmitting the video drawing command and the switching control command output from the display device to the display device, wherein the display device receives the transmitted video drawing command and the switching control command. Second digital interface means, and switching control for outputting a switching instruction based on a switching control instruction received by the second digital interface means or an instruction relating to video processing input externally separately from the switching control instruction Means, and in accordance with a switching instruction output from the switching control means, synchronously or asynchronously with a synchronous signal input from outside separately from the video rendering command, the video rendering received by the second digital interface means. Digital video Drawing processing means for generating image data and a synchronizing signal, and outputting a selection signal in accordance with a switching instruction output from the switching control means; and temporarily storing and outputting the digital video data generated by the drawing processing means Image memory means, digital / analog conversion means for converting the digital video data output from the image memory means into an analog video signal and outputting the same, and externally input according to a selection signal output from the drawing processing means. Selecting means for selecting and outputting any one of an analog video signal input from the outside together with the synchronizing signal and an analog video signal output from the digital / analog converting means; and an analog signal output from the selecting means. A video signal based on the video signal and the synchronization signal created by the drawing processing means; Digital image display system characterized in that it comprises an, and display means for displaying. 3. An image display system comprising: a digital data output device; and a display device for displaying a video transmitted from the digital data output device, wherein the digital data output device is for displaying a video. A CPU for creating and outputting a video drawing instruction;
And first digital interface means for transmitting the image rendering command output from the display device to the display device, the display device receiving the transmitted image rendering command, the second digital interface means, Drawing processing means for generating digital video data and a synchronizing signal based on the video drawing command received by the second digital interface means; and temporarily holding the digital video data generated by the drawing processing means and then outputting Image memory means for converting the digital video data output from the image memory means into an analog video signal and outputting the analog video signal; the analog video signal output from the digital / analog conversion means and the drawing Synchronization signal created by processing means Display means for displaying an image based on the display means, and an analog sensor connected to an external sensor for detecting and outputting a display state of the display means, converting a detection signal output from the external sensor into digital detection data and outputting the digital detection data. Digital conversion means, calculation means for generating characteristic data of the display device by calculation based on digital detection data output from the analog / digital conversion means, and temporarily holding the characteristic data generated by the calculation processing means After that, a memory means for outputting,
A digital image display system, wherein the characteristic data output from the memory means is transmitted to the digital data output device via the drawing processing means and the second digital interface means. 4. An image display system comprising: a digital data output device; and a display device for displaying an image transmitted from the digital data output device, wherein the digital data output device is used for displaying an image. A CPU that creates and outputs a command and a switching control command for performing switching control; a drawing processing unit that creates digital video data and synchronization signal data based on the command output from the CPU; Data compression means for compressing the digital video data created by the means and outputting as compressed video data, compressed video data output from the data compression means, synchronization signal data created by the drawing processing means, and the CPU The switching control command output from the The first digital interface means for transmitting the compressed video data, the synchronization signal data and the switching control command transmitted from the first digital interface means, respectively; A switching control means for outputting a switching instruction based on a switching control command received by the digital interface means or an instruction relating to video processing input from the outside separately from the switching control command; In accordance with the switching instruction, the compressed video data received by the second digital interface means is decompressed in synchronism with or asynchronously with a synchronization signal input from outside separately from the compressed video data and the synchronization signal data. To the original digital video data Data expansion means for generating a synchronization signal from the synchronization signal data received by the second digital interface means, and outputting a selection signal in accordance with a switching instruction output from the switching control means; An image memory means for temporarily storing digital video data output from the digital video data and outputting the digital video data; a digital / analog conversion means for converting the digital video data output from the image memory means into an analog video signal and outputting the analog video signal; According to the selection signal output from the decompression means, one of an analog video signal input from the outside together with the synchronization signal input from the outside and an analog video signal output from the digital / analog conversion means are selected. Means for selecting and outputting an output from the selecting means. A digital image display system comprising: a display means for displaying a video based on a analog video signal and a synchronization signal created by the data decompression means. 5. An image display system comprising: a digital data output device; and a display device for displaying a video transmitted from the digital data output device, wherein the digital data output device is configured to perform video display. A CPU that creates and outputs a command and a switching control command for performing switching control; a drawing processing unit that creates digital video data and synchronization signal data based on the command output from the CPU; Image memory means for temporarily storing the digital video data created by the means and then outputting the digital video data, and data compression means for compressing the digital video data output from the image memory means and outputting it as compressed video data And compressed video data output from the data compression means. First digital interface means for transmitting the synchronization signal data created by the drawing processing means and the switching control command output from the CPU to the display device, respectively, wherein the display device is A second digital interface means for receiving the compressed video data, the synchronization signal data and the switching control command, and a switching control command received by the second digital interface means or an external input separately from the switching control command. Switching control means for outputting a switching instruction based on an instruction relating to video processing, and synchronizing with an externally input synchronization signal separately from the compressed video data and synchronization signal data in accordance with the switching instruction output from the switching control means Or asynchronously The compressed video data received by the second digital interface means is decompressed and output as original digital video data, and a synchronization signal is generated from the synchronization signal data received by the second digital interface means. Data expansion means for outputting a selection signal in accordance with the switching instruction output from the switching control means, digital / analog conversion means for converting digital video data output from the data expansion means into an analog video signal and outputting the same, According to the selection signal output from the data decompression means, any one of an externally input analog video signal together with the externally input synchronization signal and an analog video signal output from the digital / analog conversion means is output. Selecting means for selecting and outputting; A digital image display system comprising: display means for displaying an image based on an analog video signal output from the selection means and a synchronization signal created by the data decompression means. 6. An image display system comprising: a digital data output device; and a display device for displaying a video transmitted from the digital data output device, wherein the digital data output device is for displaying a video. A CPU for creating and outputting a video drawing instruction;
And first digital interface means for transmitting the image rendering command output from the display device to the display device, the display device receiving the transmitted image rendering command, the second digital interface means, Drawing processing means for generating digital video data and a synchronizing signal based on the video drawing command received by the second digital interface means; and temporarily holding the digital video data generated by the drawing processing means and then outputting Image memory means for converting the digital video data output from the image memory means into an analog video signal and outputting the analog video signal; the analog video signal output from the digital / analog conversion means and the drawing Synchronization signal created by processing means Display means for displaying an image based on the command signal, and an input device for inputting a command from the outside and outputting the command signal as a command signal. The command signal output from the input device is connected to the second device.
And an input device interface means for sending the command signal to the digital data device when the command signal is sent from the input device interface means. A digital image display system, wherein the digital image is transmitted to a computer. 7. The digital image display system according to claim 1, wherein said first and second digital interface means comprise general-purpose interface means based on general-purpose interface specifications, A digital image display system, wherein a computer peripheral device having the general-purpose interface means can be connected between the first and second digital interface means. 8. The digital image display system according to claim 1, wherein the digital image display system comprises one digital data output device and a plurality of the display devices. Digital image display system. 9. A digital image display system according to claim 1, wherein said second digital interface means includes means for changing an operation state of said drawing processing means or image memory means to said digital data. A digital image display system which can be transmitted to an output device. 10. The digital image display system according to claim 1, wherein said digital data output device is a computer main body, a CD-R.
OM device, hard disk device, magneto-optical disk device,
Digital VTR, digital camera, scanner device,
A digital image display system comprising a modulation / demodulation device connected to a communication line or a demodulation device for receiving broadcast radio waves and reproducing it as video data.