JP2989057B2 - Character / graphic superimposition video 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 method and system for superimposing characters and graphics on a reproduced video signal (for a still image) which is recorded and reproduced repeatedly by recording a video signal.

[0002]

2. Description of the Related Art A conventional superimposing method of characters and figures for a video signal is disclosed in US Pat.
PECIAL NO. 5. “Special Features on Image Processing Circuit Technology” (1987), Chapter 5, “Design and Production of NTSC (Input Composite Video Signal) Decoder and Superimposer”, pp. 41-65. Conventionally, the type of input video symbol (video signal for superimposing a character or figure), the type of CRT to be displayed, and the superimposition control method to be handled are different depending on the type of display, but the composite video signal (NTSC signal) is not used. As a handling method,
Video processing is performed on a video signal reproduced after recording, and superimposition control is performed.

[0003]

In the prior art described above, in particular, in a method of superimposing a character or a figure on a still image signal in which a recorded video signal is repeatedly reproduced, a synchronization signal is converted from a recorded video signal. Superimpose control is performed by a superimposition control signal that is separated and synchronized with an external device or a character / graphics generating unit. Therefore, in a device or system that has a plurality of individual lines, each line separates the synchronizing signal from the video signal, and superimposes the graphic character, and outputs by adding a sync signal again.

Conventionally, in a device or a system having a plurality of individual lines, after separating a synchronization signal,
When superimposing different characters / graphics on different lines and superimposed reproduction screens for each line, it is necessary to control line connection, video recording, reproduction and superimposition of character / graphic for each line. Therefore, in the device or system that requires control of the plurality of lines, control is required for each line, respectively and a control unit, also hard interface and software interface with each line 必
It becomes important. In other words, conventionally, synchronization separation etc.
Video signal processing and superimposition control
The size of the hardware,
This is a problem for miniaturization and economy.

The present invention relates to a character / graphic superimposition having a plurality of lines.
In video systems, miniaturization of circuit scale and system
It aims at miniaturization and economy.

[0006]

[0007]

In order to achieve the above-mentioned object, a character / graphic superimposition display for outputting a video signal for each of a plurality of lines is provided.
In the image system, the plurality of lines are provided in common.
And a line corresponding unit provided for each of the plurality of lines.
And the common unit generates a synchronization signal from the video signal.
A separating part to be separated, and the same part separated by the separating part.
Sampling unit for digitizing the video signal in accordance with a period signal
According to the synchronization signal separated by the separation unit
A display area that indicates the area on the display
Display area for each video image display screen.
(A) a creation unit and character / graphic information displayed in the display area
A character / graphic generating unit for generating a report, and a digital
Video signal and the display screen of the video signal
Display area created by the display area creation unit
And a control unit for issuing a write instruction to the line.
The unit, when instructed to write by the control unit,
The video signal digitized by the sampling unit is converted to the synchronization signal
A video signal recording unit that records for each display screen according to
When a writing instruction is given by the storage controller, the display
The display area created by the rear creation unit follows the synchronization signal.
A display area recording unit for recording for each display screen,
Character diagram generated by the character / graphic generator according to the synchronization signal
A character / graphic recording unit for recording shape information;
Unit and the display area recording unit, synchronized with the synchronization signal
And read out for each of the display screens.
A) According to the display area read from the recording unit,
Video corresponding to the area of the display screen on which the character graphic is superimposed
When a signal is read, it is recorded in the character / graphic recording section.
Means for reading out character / graphic information,
The character / graphic information read from the graphic recording unit and the video signal
Superimposing section for superimposing the video signal read from the signal recording section
And

[0008] Further , the line corresponding section is multiplexed.
Extraction unit that extracts the video signal addressed to itself from the video signal
Can be obtained.

[0009]

[0010]

[0011]

[0012]

[0013]

[0014]

[0015]

A synchronizing signal (for example, a horizontal synchronizing signal, a vertical synchronizing signal, and other corresponding input composite signals that can be used as position information on a screen) from an input composite signal to be recorded in a memory corresponding to each line by a sync separation circuit. ). The display area creation unit creates a display area indicating the position information where the character or figure on the screen is superimposed on the basis of the synchronization signal of the input video signal.

When the detection of the synchronization of the input video signal is completed and the display area creating section is stabilized, the input video signal is input at a certain timing (for example, at the head of the frame, at the head of the line, or in the odd or even field). The signal is recorded in the video signal recording unit. At the same time, the above-described recording of the display area is also performed. The input composite video signal thus recorded and the display area corresponding to the corresponding screen are recorded in a state in which synchronization signals such as a horizontal synchronization signal and a vertical synchronization signal on a monitor (TV) screen are synchronized. Therefore, if the playback control of the video signal and the playback control (readout control) of the medium (memory or the like) on which the display area is recorded are controlled at the same timing, the display area of the character or graphic required for the playback video signal becomes Because it is always synchronized (stable)
Even if a malfunction occurs or a character or figure is superimposed on the corresponding reproduced video signal, no synchronization is lost.

According to this method, even if the input video signal to be recorded contains a little jitter (synchronization which can be pulled in by the monitor TV on the terminal side, an allowable error in the station, etc.).
Since the synchronization signal is extracted each time the input composite video signal is recorded, a display area corresponding to the corresponding reproduced video signal can always be obtained.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the circuit diagram shown in FIG. In FIG. 1, an input video signal sampling unit 01 samples an input composite video signal using a sampling clock Nfsc, converts the input composite video signal into a digital signal, and outputs the digital signal. Input video signal synchronization signal separation unit 02
Separates a video synchronization signal (a horizontal synchronization signal, a vertical synchronization signal, a signal indicating an odd or even field, a signal indicating a frame, etc.) from an input composite video signal. Multiple input composite video signals can be input,
Switching can be selected by the host controller. The host control device includes an input unit for receiving an input instruction for character / graphic information, and a display unit for monitoring video information and the like. The synchronizing signal separation unit 02 has a synchronizing signal stable state monitoring function for monitoring that the synchronizing signal of the input video signal is stabilized within an allowable value, in order to cope with a case where the switching of the input composite video signal is selected. When the switching is performed and the synchronization signal of the input video signal is stabilized, a synchronization pull-in completion signal SCOK is notified to the control unit 03.
(Note that the control unit 03 can arbitrarily read the synchronization pull-in state as a status from the synchronization signal separation unit 02.) The synchronization signal of the stable input video signal extracted by the synchronization signal separation unit 02 and within the allowable value is Display area creation unit 0
It is conveyed to 4. The display area creation unit 04 creates a display area on the screen where the character or graphic for the input composite video signal is superimposed, that is, superposition position control information, based on the stable synchronization signal.
When receiving the synchronization pull-in completion report signal SCOK, the control unit 03 synchronizes the video signal (data) created by the sampling unit 01 with the superimposition control information created by the display area creation unit 04, and To the video signal recording unit 0
5 and the superimposition control information recording unit 06
It instructs the te control unit 07. The video signal recording unit 05 and the superimposition control information recording unit 06 write the recording data via the Write control unit 07 in accordance with the instruction of the control unit 03. Both of these two recording units perform the recording of the input video signal. It operates by a clock synchronized with a sampling clock Nfsc for performing sampling. The two recording units manage recording data in units of frames or fields corresponding to the input composite video signal. For this reason, the video signal recording unit 05 is divided into regions for two frames, and further divided into odd fields and even fields of the video signal in one frame. Writing and reading are performed for each area. This is for the purpose of easily maintaining the continuity of the image data at the time of reproduction, and Read information for notifying the Write control unit 07 in which frame or field reading of the reproduced image data is performed (this Read information is Wr.
It may be used for issuing the item timing. ) To prevent the rewrite instruction from the Write control unit 07 from overlapping with the address being reproduced. This is also effective for smoothly changing the screen output to the terminal. As described above, at the same time when new image data is written to the video signal recording unit 05, display area information for superimposing characters and / or graphics on the newly written image data is also written to the superimposition control information recording unit 06.
Note that reproduction (reading) of the two recording units, the video signal recording unit 05 and the superimposition control information recording unit 06, is synchronized with the sampling clock Nfsc of the video signal as described above, and is continuously repeated (read). ). The character / graphic information recording unit 08 stores character or graphic information superimposed on the reproduced video screen by the character / graphic generation unit 09.
It is recorded corresponding to the scanning line in the display area. Character or graphic information can be input from a higher-level control device. The writing of the character / graphic data from the character / graphic generating unit 09 to the character / graphic information recording unit 08 is performed while the video signal other than the character / graphic display area is being reproduced by the Read information from the superimposition control information recording unit 06. . This allows characters or figures to be superimposed even when the video signal is not rewritten, so that writing or erasing can be performed at any time under the control of the control unit. Since the operation is performed during scanning, the superimposing operation of the character and graphic is performed smoothly. The character / graphic data recorded in the character / graphic information recording unit 08 is a Read signal (which is a signal indicating a display area on the screen) which is repeatedly read from the superimposition control information recording unit 06 in synchronization with a reproduced video (screen) signal. ). The character and graphic information read from the character / graphic information recording unit 08 are added to the reproduced video signal reproduced from the video signal recording unit 05 to become a superimposed reproduced video signal.

Next, the operation when superimposing a character or a figure will be described with reference to FIG. The input composite video signal (NTSC) is sampled by the input video signal sampling unit 01 with the sampling clock Nfsc and converted into a digital signal. The digitized signal is recorded in the video signal recording unit 05 while including the synchronization signal.
The same input composite video signal is also input to the input video signal synchronization signal separation unit 02 at the same time. When the synchronization signal of the input video signal is stabilized, the input video signal synchronization signal separation unit 02 outputs the synchronization pull-in completion signal SCOK to the control unit. Notify 03. Also, the input video signal synchronization signal separation unit 02
The sampling clock Nfs is the same as the sampling unit 01.
The video synchronizing signal is extracted in real time from the corresponding input composite video signal by c or a clock synchronized with the clock. The display area creation unit 04 creates a display area on the screen based on the video synchronization signal. Creation of the display area will be described later. The created display area information records the displayable area and the non-displayable area of the information of the video data in the superimposition control information recording unit 06 in synchronization with the video data. In response to the synchronization pull-in completion signal SCOK, the control unit 03 synchronizes the video signal (data) encoded by the sampling unit 01 with the superimposition control information created by the display area creation unit 04 to synchronize each data. Is output to the Write control unit 07. Write control unit 07 instructs writing to each recording unit. The character / graphic generating unit 09 generates character / graphic information to be superimposed in advance and stores the information in the character / graphic information recording unit 08. Character / graphic information recording unit 0
Numeral 8 indicates that a read signal is output from the superimposition control information recording unit 06 when the area is a displayable area and character / graphic information is output. The Read signal is not output in an area where display is not possible. Thus, the character / graphic information recording unit 08 outputs the character / graphic information at the time of the displayable area, and rewrites the character / graphic at the time between the non-displayable areas. That is, the superimposition control information recording section serves as control means for superimposing control of the character / graphic information of the character / graphic information recording section on the video signal.

Next, the configuration of the display area creating unit will be described. FIG. 3 shows an internal block diagram of the display area creating unit, and the description will be made with reference to FIG. The display area corresponds to the scanning line. Therefore, the dot counter 31 counts dots using the sampling clock Nfsc of the video signal as a clock, and is cleared by the horizontal synchronization signal. The line counter 32 counts horizontal lines using the horizontal synchronization signal as a clock, and is cleared by a frame signal. The N-bit parallel outputs from these two counters are superimposed to form one address and input to the display area conversion memory 33. In the display area conversion memory 33, a display area or a non-display area is stored in advance as 1 or 0 for each address. The display area conversion memory 33 can issue a change instruction, and can input a display area change address and display area change data from the host controller.

FIG. 2 is a block diagram showing an embodiment in which the present method is applied to an apparatus or system having a plurality of lines.

As shown in FIG. 2, a common part having a common character / graphic superimposition synchronizing signal processing circuit for generating a character / graphic superimposition control signal of an input video signal, and a video corresponding to each line connected to an output terminal. A plurality of line corresponding units for outputting signals.

The character / graphic superimposing synchronization signal processing circuit has a common part as shown in FIG. That is, a sampling section 01 for sampling a composite video signal, a synchronization signal separation section 02 for extracting a synchronization signal from the composite video signal, and a display area for creating a display area indicating superimposition position information for superimposing character / graphic information. It has a creating unit 04 and a control unit 03 that controls the common unit. The control unit 03 can receive an input from a higher-level control device. Further, a common character / graphics generating unit 20 for generating character / graphic information of characters and / or graphics to be superimposed on the reproduced screen is provided, and character / graphic information can be generated for each line. The character / graphic information can generate information for each line separately.

The line-corresponding unit includes a video signal recording unit 05 for recording an input video signal as a composite video signal including a synchronization signal, and a character and / or a character superimposed on a reproduced screen.
Alternatively, a character / graphic information recording unit 08 that records character / graphic information of a figure in synchronization with a video signal synchronization signal, and character / graphic information of a character / graphic information recording unit based on a display area created by a display area creation unit. Control information recording unit 06, which is a control unit for superimposing control on video signals, and a Write control unit 0, which instructs each recording unit to write and read.
7 are provided.

The common unit further includes a multiplexing unit that multiplexes information to be output to a plurality of output terminals and outputs the multiplexed information. The line corresponding unit extracts information addressed to itself from the multiplexed information. It further has an extraction unit. Thus, without providing a line connecting the common unit and the line corresponding unit,
A multiplexed bus can be used with a common line.

Next, the operation of the system shown in FIG. 2 will be described.

The input composite video signal is converted into video data by a video signal common processing section 10 corresponding to the common section shown in FIG. 1, and position data for displaying characters and / or graphics synchronized with the video screen. Is converted to
Recording of the two synchronized data of the video data and the position data is performed by controlling the recording only on the line for which writing or rewriting is to be performed in accordance with an instruction from the control unit 03 or a higher-level control device. The subscriber can check the new video that has been written. Similarly, the character and / or graphic data to be superimposed is also the character / graphic generating unit 2 of the common part shown in FIG.
0, the recording control is performed only on the necessary line according to the instruction of the control unit 03 or the higher-level control device, thereby performing the superimpose control on the relevant line.

Further, as shown in FIG. 2, the transfer of data and control information between the common unit and each line corresponding unit is connected by a multiplexed BUS, so that the common unit located on the input side is connected to each line. In addition to being able to share, the hardware configuration of the device can be simplified and downsized.

Conventionally, in an apparatus or system having a plurality of lines to be controlled, video signal processing such as synchronization separation or superposition control is performed for each line, so that the hardware scale becomes large and software processing is performed. His ability had also declined.

According to the above embodiment, the synchronizing signal processing circuit is provided in the common section, and the size of the character / graphic superimposition control circuit for each line is reduced, thereby making it possible to reduce the size of the apparatus or the entire system. Then, by placing also graphic character generator controlled by the control unit (CPU or host device) to the common portion, a hard interface with the control unit simplified, it is the child to allow the economy of the system.

Image data, superimposition control data, and character / graphic data between a common control unit such as a video signal synchronizing / separating circuit and a character / graphic generating unit for superimposing character / graphics and each line corresponding unit are multiplexed. By using the BUS connection, immediate responsiveness can be realized, the system can be downsized, it is economical, and the circuit configuration can be simplified.

Further, the present invention is effective for a system requiring an immediate response such as a man-machine interface when a plurality of lines are provided in an interface between terminals (subscriber lines).

According to the present invention, only the common portion has a circuit configuration.
Superimpose control with complicated synchronization signal processing circuit
The signal is provided in the line-corresponding section simultaneously with the recording of the video signal.
The synchronization signal processing circuit is shared by
Circuit size and economical
In addition, the size of the character / graphic superimposition circuit in the line section should be reduced.
To reduce the circuit size and economics of the entire system
can do.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing an embodiment of the present invention.

FIG. 2 is a configuration diagram when the present invention is applied to an apparatus or a system having a plurality of output lines.

FIG. 3 is an internal block diagram of a display area creation unit.

[Explanation of symbols]

01: sampling unit, 02: synchronization signal separation unit, 03: control unit, 04: display area creation unit, 05: video signal recording unit,
06: superimposition control information recording unit, 07: Write control unit,
08: Character / graphic information recording unit, 09: Character / graphic generation unit, 1
0: video signal common processing unit, 20: character / graphic common generation unit,
Reference numeral 30: Line corresponding unit.

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-2-82769 (JP, A) JP-A-2-62593 (JP, A) JP-A-2-82770 (JP, A) JP-A-3-82 52388 (JP, A) JP-A-63-54887 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H04N 5/262-5/28

Claims (2)

(57) [Claims] A character diagram for outputting a video signal for each of a plurality of lines
A superimposed image system, wherein a common part provided in common to the plurality of lines;
And a line corresponding unit provided for each of the lines, wherein the common unit has a function of separating a synchronization signal from the video signal.
A separating unit and the synchronization signal separated by the separating unit.
A sampling unit for digitizing the video signal,
On the display screen according to the synchronization signal separated by the separation unit
The display area indicating the area where the character graphic
Display area creation unit for each video signal display screen
Generates character / graphic information displayed in the display area.
A character / graphic generating unit to be digitized by the sampling unit.
Corresponding to the video signal and the display screen of the video signal,
Writing with the display area created by the display area creation unit
And a control unit for performing a write instruction , wherein the line corresponding unit is instructed to write by the control unit.
The video signal digitized by the sampling unit
Video signal to be recorded for each display screen according to the synchronization signal
When a writing instruction is given by the recording unit and the control unit
The display area created by the display area creation unit
Display area for recording on each display screen according to the synchronization signal
A recording unit, and the character / graphic generating unit according to the synchronization signal.
A character / graphics recording unit for recording generated character / graphics information;
From the video signal recording unit and the display area recording unit,
Reading is performed for each display screen in synchronization with the synchronization signal.
The display area read from the display area recording unit.
The area on the display screen where the text and graphics are superimposed
The character diagram when the video signal corresponding to the area is read out
Read character / graphic information to be recorded in shape recording unit
Means and a character graphic read from the character graphic recording unit
Information and a video signal read from the video signal recording unit;
And a superimposing unit for superimposing a character.
Superimposed video system. 2. A system for superimposing a character and graphics according to claim 1.
In the system, the line corresponding unit is a
An extraction unit that extracts the video signal addressed to itself from the signal
And a character / graphic superimposed video system.