JPH01109393A - Video animation display area assigning system for work station - Google Patents

Abstract

PURPOSE: To display a video dynamic picture on an optional position of a virtual terminal screen by an optional shape in each dot and to prevent colors to be used for the virtual terminal screen from being restricted by combining a level detector, a display area setting register and a mode setting register. CONSTITUTION: A CR controller 2 reads out a picture signal from a frame memory 3 through synchronizing signals 17, 18 and outputs the read signal to a signal switch 10 through an A/D converter 4. The levels of R, G and B signals in a video signal are judged by a level detector 16, and when the levels are less than a threshold level, an external video signal 16 is displayed. When the levels are over the threshold level, the signal 15 is displayed. A display screen switching signal generator 9 logically operates the combination of display screen selecting signals 19, 20 based upon a mode signal 21 outputted from a mode setting register 8, and when a processor generates a black virtual terminal screen in the memory 3, the signal 16 is displayed on the generated screen. A display area specification memory 7 specifies an area for displaying the signal 16.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a workstation that inputs a video signal to the workstation and displays a video moving image, and particularly relates to a video signal level detector and a moving image frame specification area. The present invention relates to a workstation suitable for displaying video motion pictures in a variety of formats in combination with memory.

[Conventional technology]

On workstations with traditional virtual terminal functionality, a second
As shown in the figure, a virtual terminal screen created by a processor 1 in a frame memory 3 via a bus 12 is converted into an analog workstation video signal by a D/A converter 4, and converted into an analog workstation video signal for a display 11 as shown in the figure. 15 and an externally input video signal!
! Rectangular area-television signals were displayed by mixing at 24.

[Problem that the invention seeks to solve]

The above conventional technology does not take into account the possibility of displaying a video in an arbitrary shape, can only display a video in a rectangular shape, and can specify the horizontal position and display status only in units of characters, not units of dots. There was a problem. Furthermore, when displaying a video moving image, there is a problem in that the colors used on the overlapping screen and the colors used on other virtual terminal screens are restricted. More specifically, the function of displaying an external video signal in a rectangular area is realized by the CRT controller 3, such as the Hitachi CRT controller HD634.
5 (CRTC-II), the rusk scan type CRT
Generates various timing signals for the display.

FIG. 2 shows a system configuration for displaying a television signal on a virtual terminal screen while synchronizing with the television signal using the television synchronization mode of the CRT controller.

In this configuration, although it depends on the function of the CRT controller, in the case of the HD6345, the vertical display position can be set in rask units, and the horizontal display position can be set in character units, but it is not possible to display in an arbitrary shape only in a rectangle. , the only way to display a virtual terminal screen with only video moving images is to dim the level of the frame memory output video signal (
For example, when displaying a video (for example, by specifying black as the video area), there are drawbacks such as restrictions on the colors that can be used on other virtual terminal screens.

SUMMARY OF THE INVENTION An object of the present invention is to provide a workstation that allows video moving images to be displayed dot by dot in arbitrary shapes and at arbitrary positions on a virtual terminal screen, and which does not limit the colors used on other virtual terminal screens.

[Means for solving problems]

The above purpose is to perform workstation D/A (Digit
A signal switcher for switching between (al/Analog) conversion output and video video signal output, and for signal switching,
A level detector is provided to detect the level of the D/A conversion output of the workstation.

By providing a memory 7 for specifying a video display area in synchronization with the dot output timing, the video display area can be specified by the memory 7, and the level detector can realize superimposition of the video video and the workstation screen. This is achieved by creating a video region with an arbitrary shape at an arbitrary position.

[Effect]

The workstation according to the present invention has five means for displaying a video moving image on a virtual terminal screen: a level detector 1 display area designation memory, a display mode setting register, a display screen switching signal generator, and a signal switching device. . The first means, a level detector, detects when the analog video signal output produced by the workstation exceeds a defined level.

It is set to logic "1" and outputs logic "0" when it does not exceed it. The output of the level detector is input to a single display screen switching signal generator and becomes one of the video animation and workstation video output screen selection signals.

The second means, the display area specifying memory, sets the display area of the video moving image by the processor, and outputs the contents of the display area specifying memory to the one display screen switching signal generator in synchronization with the dot clock of the display screen. This operates as one of the display screen selection signals. The display mode setting register, which is the third means, sets the display mode from the processor, and the first means, which is a mode that uses only the level detector output, and the second means, which is the output of the display area specification memory A display mode signal indicating a mode in which only the video is used, a mode in which the first and second means are used together, and a mode in which no video is displayed is output to the display screen switching signal generator. Fourth
The display screen switching signal generator which is the means of the first. A logical operation is performed on the display screen selection signal outputted by the second means based on the mode signal outputted by the third means, and the result is outputted as a display screen switching signal to the signal switching device which is the fifth means. The signal switching device dynamically switches between the external video signal and the analog video signal of the workstation based on the display screen switching signal output by the fourth means.

The output of the signal switch is input to the display based on the synchronization signal detected from the external video signal, allowing the video animation and the output screen of the workstation to be displayed simultaneously on the display.

By configuring as described above, a video moving image and a workstation output screen can be arbitrarily mixed and displayed on a raster scan type display.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 and 3.

FIG. 1 shows a block diagram of one embodiment of a video signal display section of a workstation according to the present invention.

As shown in the figure, a display 11 that displays a virtual terminal screen
It is composed of a processor 1 that processes virtual terminal control, a frame memory 3, and a peripheral display control device.

An external video signal 16 is input to the workstation from the outside.

The external video signal 16 is one of the candidates for the output video signal 23.
As one, it is input to the signal switch @10.

The external video signal 16 is also input to the synchronization signal detection device 5, and the horizontal synchronization signal 17. A vertical synchronization signal 18 is extracted. Signals 17 and 18 are connected to display 11 and CR
It is output to the T controller 2 and used as a basic synchronization signal for one-screen display.

The processor 1 connects the virtual terminal screen display frame memory 3 . A CRT controller 2 that controls the frame memory 3 to display on the display 11. It is connected to an area designation memory 7 that indicates the area where the external input video signal 16 is to be displayed on the display 11, and a display mode setting register 8 that specifies the output mode of the display screen.

The CRT controller 2 reads the image signal from the frame memory 3 based on the synchronization signals 17 and 18, and converts it into an analog signal using the D/A converter 4.

As the processor side video output signal 15, the signal switch 1
0 as another input. The processor side video output signal 15 is a basic luminance signal of a color video signal, R
(Rad) signal, Q (Green) signal.

It consists of three signals, a B (Blue) signal, and a level detector 6 determines the level of each of these R, G, and H signals. Here, in order to display a video moving image, R,
When all the G and B signals are below a predetermined threshold level, the output of the level detection l16 becomes logic "0".

If the output of the level detector is logic "0", which is logic "1" at other times, external video signal 16
Logic "1" indicates a request to display the video output signal 15 on the processor side.

For example, when the detection level is set to the lowest level, the processor video signal 15 can display an arbitrary shape external video signal at an arbitrary position on the display 11.

When an external video signal area is specified in the display area specification memory, any color can be freely used for the processor side video signal.

The mode setting register 8 is a register for specifying a combination of the above two display methods, and can be configured with a 2-bit register, for example, so that four modes can be set. The first mode is a mode in which only the output of the level detector 6 is used as the display screen switching signal 22, and the second mode is a mode in which only the output of the level detector 6 is used as the display screen switching signal 22.
The third mode is a mode in which only the output of the display area designation memory 7 is used as the display screen switching signal 22, the third mode is a mode in which the logical product of the output signals 6 and 7 is used as the display screen switching signal, and the fourth mode is
These modes are all modes in which the one-display screen switching signal 22 is fixed at logic "1" in order to display the processor-side video signal.

In order to realize the above four modes, the display screen switching signal generator 9 performs a logical operation on the combination of display screen selection signals 19 and 20 based on the mode signal 21 output from the mode setting register 8, and switches the display screen. A request signal for displaying the external video signal 16 in the black portion of the signal 22 is output from the level detector 6 as a display screen selection signal 19 to the display screen switching signal generator 9.

That is, if the processor generates a black virtual terminal screen in the frame memory 3, when the external video signal wants to superimpose the 0 character displayed on the black virtual terminal screen, on this black virtual terminal screen, This can be realized by displaying a character with a luminance higher than the threshold level of the level detector.

However, at this time, on other virtual terminal screens, the external input video signal is also superimposed on portions where colors below the threshold level are used.

Next, the display area designation memory 7 constitutes a 1-bit memory corresponding to a dot on the display screen in order to indicate the area where the external video signal is displayed, and is configured with a logic "0" from the processor.
The area set with `` is the area where the external video signal 16 is displayed, and the area where the logic ``1'' is set is the area where the processor side video output signal 15 is displayed.

Any pattern can be specified for dot correspondence.

FIG. 3 shows a diagram of the principle of the level detector 6.

When level detection is performed using the R signal of the processor-side analog video signal 15 as an example, the R signal as shown in FIG.
When the signal VR is input to the level comparator 25 and exceeds the threshold voltage Vth, an output that becomes logic "1" appears on the comparator output signal 26-1.

The G signal and B signal were generated in the same manner.

Comparator output signal 26-2, 26-3 and the above 26-
1 is logically summed to obtain a display screen selection signal of 1.9.

In this way, when all of the R, G, and B signals are below Vth, the display screen selection signal 19 becomes logic "0", making it possible to specify display of the external video signal.

FIG. 3(b) shows the setting relationship between the video signal voltage and Vth when the brightness gradations of R, G, and B are each 8 gradations.
aVth where the external video signal is displayed when is 4 or less
If the brightness level is set to 1 or less, the external video signal will be displayed only when 15 is black.

Another way to set the threshold is to limit it to one arbitrary color, so that only one color is restricted outside the area where the external video signal is displayed.

Also, the level detection method uses R, G, and B signals.

In the method of comparing only the added luminance signals, the limited colors are more limited, and the comparator is also small and inexpensive.

As described above, according to this embodiment, it is easy to set an external video signal display area of any shape at any position on the workstation display, and the function of the mode setting register allows for a wide variety of external video signal display areas. A superimpose mode can be achieved.

(Effects of the Invention) According to the present invention, by combining a level detector, a display area setting register, and a mode setting register, it is possible to easily set the area on the virtual terminal screen of a workstation. When superimposing with the output screen, the colors used can be arbitrarily restricted, allowing a variety of superimposition screens to be constructed, and is effective in organically utilizing the work flow and other video equipment.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of a video signal display section of a workstation according to the present invention, and FIG. 2 is a diagram. A configuration diagram of a video signal display section of a conventional workstation. FIG. 3(a) is a diagram of the principle of level detection used in the present invention. FIG. 3(b) is a diagram of setting the video output voltage and brightness level. Show a graph showing the relationship. 1... Processor, 2... CRT controller, 3
...Frame memory, 4...D/A converter, 5...
・Synchronization signal detection device, 6... Level detector, 7...
Display area specification memo 1c 8...Display mode setting register, 9...Display screen switching signal generator, 10...Signal switcher, 11...Display, 12...Processor bus, 13... Display timing signal, 14... Digital image data, 15... Processor side video output signal, 16... External input video signal, 17... Horizontal synchronization signal, 18... Vertical synchronization signal, 19. 20...
Display screen selection signal. 21... Display mode signal, 22... Display screen switching signal, 23... Output video signal, 24... Mixing device, 25... Comparator, 26-1.2.3...
- Comparator output signal, 27... logical sum.

Claims (1)

[Claims] 1. In a workstation having a virtual terminal control function, a first means for detecting the level of a screen output signal of the workstation, a second means for storing a video display area, the first means and the second means; a third generating mode for specifying logical combinations of the outputs of
and a fourth means for performing a logical operation on the outputs from the first, second, and third means and outputting a screen selection signal for switching between an externally input video signal and an image output signal of the workstation. and fifth means for dynamically switching the output video signal based on the screen selection signal output from the fourth means. .