KR0137264B1 - Apparatus for displaying screen of multi video signals - Google Patents

Abstract

The screen display apparatus of the multiplexed video signal displays on the screen a multiplexed video signal including video signals of several channels and a channel identifier code for distinguishing the multiple channels from each other. The sync separator constituting this apparatus detects a sync signal from the multiplexed video signal coming through the input terminal. The identifier reading unit detects the channel identifier code from the multiplexed video signal based on the synchronization signal detected by the synchronization separation unit. The user selects desired channels through the selection channel input unit, and the controller generates a plurality of selection channel data representing the selected channels and sequentially outputs the plurality of selection channel data according to the synchronization signal detected by the synchronization detection unit. The channel comparison unit compares each of the plurality of selected channel data from the control unit with the detected channel identifier code, and outputs a comparison result signal representing each comparison result. The selection output unit outputs the multiplexed video signal inputted through the input terminal from among the output terminals corresponding to several channels through the output terminal determined by the comparison result signal of the channel comparator and the selection channel data of the controller. The image display unit has input terminals individually corresponding to output terminals of the selection output unit, and simultaneously displays image signals received through the input terminals. Therefore, the present invention has an effect that can greatly reduce the time required to display a video signal of several channels on the screen (display).

Description

Display device of multiplexed video signal

1-a is a conceptual diagram showing a recording form of a general video tape,

2 is a block diagram showing an apparatus for displaying a multiplexed video signal according to an exemplary embodiment of the present invention;

3 is a conceptual diagram for explaining an embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

24: Channel Comparison

28: control unit

31: Selective output unit

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screen display apparatus for multiplexed video signals. In particular, the present invention relates to multiplexing for simultaneously displaying video signals from different channels recorded and multiplexed on a single storage medium on a single screen. The present invention relates to a screen display device of a video signal.

Closed-circuit television (CCTV) systems record images taken with multiple cameras on videotape, and then play back the recorded images on a monitor so that the user can identify abnormalities in the monitoring location. A conventional video signal recording / reproducing method for a closed circuit television system is obtained from eight cameras (or sixteen cameras) using a frame sequential switch (FSS) having eight (or sixteen) input stages. The input video signal is multiplexed and recorded, and reproduced on one screen for each channel.

FIG. 1 is a conceptual diagram showing a recording format of a general video tape. FIG. 1A shows a frame recording method and FIG. 1B shows a field recording method. Fig. 1C shows a field unit recording method at the time of low speed photography. Incidentally, in Fig. 1, the numbers 1 to n denote channel identifier codes used for multiplexed recording.

A conventional closed circuit television system selects a camera in video frame (1/30 second) units to distinguish video signals input and stored through a plurality of video cameras, and within the vertical blanking period of the video signal obtained by the selected camera. Insert the channel identifier code. Therefore, the user can reproduce only the video signal of the desired channel, that is, the video signal received by the desired camera and recorded on the video tape.

In such a conventional system, using a two-hour recording tape requires two hours by eight channels = 16 hours to display all the images recorded by eight cameras on one screen. Therefore, the conventional method not only causes unnecessary time waste due to reproduction of video signals of all channels, but also inconveniences of rewinding the tape in order to reproduce video signals of other channels.

An object of the present invention for solving the above problems is to receive a video signal of multiple channels repeatedly output in a predetermined data unit detects the synchronization and identifier code, and selectively only the video signal having an identifier code that matches the channel selected by the user By synchronizing and multiplexing, and displaying a plurality of images on one screen, not only eliminates unnecessary time wasted by reproducing video signals of all channels, but also reproduces video signals of other channels. It is an object of the present invention to provide a display device of a multiplexed video signal that can eliminate the inconvenience of rewinding a tape.

An object of the present invention as described above is a screen display of a multiplexed video signal displaying a multiplexed video signal including a channel identifier code for distinguishing the video signals of video signals of multiple channels and the video signals of multiple channels from each other. An apparatus comprising: an input terminal for receiving the multiplexed video signal; synchronization detection means for detecting a synchronization signal from the multiplexed video signal received through the input terminal; Identifier reading means for detecting a channel identifier code from the multiplexed video signal input through the input terminal based on the synchronization signal detected by the synchronization detecting means; Selection channel input means for selecting at least two channels among the various channels; Control means for generating a plurality of selection channel data indicative of channels selected by said selection channel input means, and sequentially outputting the generated plurality of selection channel data according to a synchronization signal detected by the synchronization detection means; Channel comparison means for comparing each of the plurality of selection channel data supplied from the control means with the channel identifier code detected by the identifier reading means, and outputting a comparison result signal indicative of each comparison result; Output stages corresponding to the various channels, respectively, and output the multiplexed video signal through the input terminal through the output terminal determined by the comparison result signal from the channel comparison means and the selected channel data of the control means Selective output means; And an input terminal corresponding to the output terminals of the selective output means, the image display means for simultaneously displaying image signals received through the input terminals. do.

Hereinafter, an embodiment of implementing a screen display device of a multiplexed video signal according to the present invention will be described in detail with reference to the accompanying drawings.

2 is a block diagram showing an apparatus for displaying a multiplexed recorded video signal according to an exemplary embodiment of the present invention, in which one screen is reproduced for reproduction of a video signal recorded on a video tape in eight channels of a frame sequence switching method (FSS). A signal processing apparatus for simultaneously displaying a plurality of images on a screen is shown.

The apparatus of FIG. 2 includes an image display unit 32 capable of simultaneously displaying a plurality of images on one screen, a signal input terminal 21 for receiving a reproduced video signal from a video tape, and a vertical image from an inputted reproduced video signal. The synchronization separator 22 which detects the synchronization signal and between 13H (H is the horizontal scanning period) and 23H (or 12H to 22H) of the reproduced video signal according to the vertical synchronization signal from the synchronization separator 22 are recorded. A plurality of selection channel data indicating a plurality of channels selected through the identifier reading unit 23 for detecting a channel identifier code, a selection channel input unit 27 for selecting a channel of a video signal to be displayed on the screen, and a selection channel input unit 27; The control unit 28 sequentially and repeatedly outputs in accordance with the vertical synchronization signal from the synchronization separating unit 22, and the channel identifier code from the identifier reading unit 23 and the selection channel data supplied from the control unit 28 are compared.And a channel comparator 24 for outputting a video signal and a playback video signal input through the signal input terminal 21 according to the output signal of the channel comparator 24 and the selected channel data of the controller 28. And a selective output unit 31 for outputting to 32.

The channel comparison unit 24 includes a serial to parallel converter (SPC) 25 for converting serial data supplied from the identifier reading unit 23 into parallel data, and the serial / parallel converter 25. And a comparator 26 for individually comparing the channel identifier code, which is output data, and the plurality of selection channel data output from the control unit 28, and generating a comparison result signal indicating whether the selected channel data compared with the channel identifier code is the same. .

The control unit 28 receives the output signal of the selection channel input unit 27, the comparison result signal from the comparator 26, and the vertical synchronization signal from the synchronization separation unit 22, and stores a plurality of selection channel data, The microcomputer 29 outputs the selected channel data and the write clock in synchronization with the vertical synchronization signal, and receives the selected channel data from the microcomputer 29, and receives the selected channel data from the synchronization separator 22. The channel selection controller 30 outputs to the comparator 26 and the selection output unit 31 in accordance with the signal.

The selection output unit 31 converts the playback video signal input through the signal input terminal 21 according to the output signal of the comparator 26 and the first switch SW1 through the first switch SW1. And a second switch SW2 for selectively supplying the reproduced video signal to the plurality of signal output terminals CH1 to CHn according to the selection channel data of the channel selection controller 30.

FIG. 3 is a conceptual diagram illustrating an embodiment of the present invention. FIG. 3a shows four selected channel images reduced by one-half-fold and displayed through one screen. FIG. 3b is a vertical scan. The period V and the channel identifiers CH1, CH3, CH5, and CH7 are shown, showing the relationship between the vertical scanning period and the selected channels 1, 3, 5, and 7 displayed on the screen.

When the video signal of 8 channels recorded on the video tape is reproduced by the frame sequential switching (FSS) method and inputted to the apparatus of FIG. 2 through the signal input terminal 21, the synchronization separating unit 22 synchronizes vertically from the input video signal. Detect the signal. The identifier reading unit 23 detects the channel identifier coded in the vertical blanking period of 13H to 23H (or 12H to 22H) of the input video signal and outputs it to the channel comparator 24. The serial / parallel converter 25 in the channel comparator 24 receives the channel identifier code, which is serial data, and converts it into parallel data.

When the user selects four channels of 1, 3, 5, and 7 of the eight channels, the microcomputer 29 in the controller 28 stores four selection channel data related to the four channels selected through the selection channel input unit 27. Then, whenever the vertical synchronization signal is applied from the synchronization separator 22, each of the four selected channel data stored in the channel selection controller 30 is sequentially stored in the latch. At this time, the microcomputer 29 generates four write clocks for storing the four selection channel data in the latch inside the channel selection controller 30 based on the vertical synchronization signal applied from the synchronization separation unit 22. Therefore, for the vertical synchronization signal applied once, four selection channel data are sequentially stored in the latch inside the channel selection controller 30. The channel selection controller 30 generates four read clocks based on the vertical synchronization signal output from the synchronization separator 22, and uses the selected channel clocks stored in the latches to use the comparator 26 to generate the four read clocks. And outputs the selection channel data output to the comparator 26 to the selection output unit 31. The comparator 26 in the channel comparator 24 receives and compares the channel identifier code from the serial / parallel converter 25 with the selection channel data from the channel selection controller 30. If the two data are the same by comparison, the comparator 26 outputs a high level signal to the first switch SW1 and the microcomputer 29. The first switch SW1, which is turned on by the high level signal from the comparator 26, corresponds to the channel identifier code used for the comparison and receives the reproduced video signal input through the signal input terminal 21, and the second switch SW2. ) As shown in FIG. 3 (b), the first switch SW1 is kept on for the input time of an image signal belonging to four channels of 1, 3, 5, and 7, 2, 4, 6, and 8. The video signal belonging to 4 channels of the camera is kept off for the time input. The second switch SW2 is configured to display the playback video signal applied from the first switch SW1 through the signal output terminal CH1, ..., or CHn selected according to the selection channel data from the channel selection controller 30. Output to (32). The second switch SW2 synchronizes the video signal input through the signal input terminal 21 with the selection channel data output from the channel selection controller 30, thereby allowing only the video signal belonging to the 1, 3, 5, and 7 channels to be displayed. Output to (32). The image display unit 32 processes four image signals output from the selection output unit 31 and displays them simultaneously on the same screen. Accordingly, as shown in FIG. 3A, images of channels 1, 3, 5, and 7 which are selected channels are simultaneously displayed on one screen.

As described above, the apparatus for displaying a multiplexed recording video signal according to the present invention can display a plurality of channels selected by a user simultaneously on one screen, and display the video signals of several channels on the screen. This can greatly reduce the time required to do so.

Claims (6)

A display device of a multiplexed video signal for displaying a multiplexed video signal on a screen, wherein the multiplexed video signal including a channel identifier code for distinguishing video signals of multiple channels and video signals of multiple channels from each other, An input terminal for receiving the multiplexed video signal; Synchronization detection means for detecting a synchronization signal from the multiplexed video signal coming through the input terminal; Identifier reading means for detecting a channel identifier code from the multiplexed video signal input through the input terminal based on the synchronization signal detected by the synchronization detecting means; Selection channel input means for selecting at least two channels among the various channels; Control means for generating a plurality of selection channel data indicating the channels selected by the selection channel input means, and sequentially outputting the generated plurality of selection channel data according to the synchronization signal detected by the synchronization detection means; Channel comparison means for comparing each of the plurality of selection channel data supplied from the control means with the channel identifier code detected by the identifier reading means, and outputting a comparison result signal representing each comparison result; Among the output stages corresponding to the various channels, the multiplexed video signal inputted through the input stage is output through the output stage determined by the comparison result signal from the channel comparing means and the selected channel data from the control means. Selective output means; And And an image display means for individually displaying input terminals corresponding to output terminals of the selective output means, and for simultaneously displaying image signals received through the input terminals. The apparatus of claim 1, wherein the synchronization signal detecting means detects a vertical synchronization signal from an input multiplexed video signal. 3. The apparatus of claim 2, wherein the control means stores a plurality of selection channel data corresponding to channels selected by the selection channel input means individually, each time one vertical synchronization signal is applied from the synchronization detection means. A microcomputer that sequentially outputs all the plurality of selected channel data; And The channel selection control unit outputs all of the plurality of selection channel data output from the micom in relation to each vertical synchronization signal to the channel comparing unit and the selection output unit each time one vertical synchronization signal is applied from the synchronization detecting unit. A display device of a multiplexed video signal comprising. 4. The apparatus of claim 3, wherein the selective output means comprises: a first switch for outputting or blocking the multiplexed video signal inputted through the input terminal according to a comparison result signal of the channel comparing means; And A second switch having output terminals respectively corresponding to the various channels, and supplying an image signal output from the first switch to the image display means through an output terminal corresponding to selection channel data from the channel selection controller; On-screen display of the multiplexed video signal provided. 5. The apparatus of claim 4, wherein the channel comparison means generates a comparison result signal for turning on the first switch when the channel identifier code and the selected channel data are the same. The apparatus of claim 1 or 5, wherein the image display means displays the image signals received through the input terminals together on one screen.