KR102254823B1 - Multi-Display System with Network-based Auxiliary Synchronous Clock - Google Patents

Abstract

A multi-display system having a network-based synchronous auxiliary clock is provided. An image reproducing apparatus according to an embodiment of the present invention includes a player reproducing one of images to be displayed on each of a plurality of displays, a first clock system providing a first clock, and a second clock system providing a second clock And a synchronization system for synchronizing an image reproduction time of a player with image reproduction times of other players using a first clock provided by the first clock system and a second clock provided by the second clock system. Accordingly, even when a problem occurs in the network-based main-clock, it is possible to precisely maintain the synchronization of video reproduction through a multi-display, an ultra-multi-view display, or the like using an internally generated sub-clock.

Description

Multi-Display System with Network-based Auxiliary Synchronous Clock

The present invention relates to a multi-display system, and more particularly, to a multi-display system that displays screens by synchronizing with a clock.

In the case of a multi-display used for displaying advertisements or information recently, or an ultra-multi-view player displayer that displays a screen on multiple displays with many viewpoints, multiple displays using the synchronization clock used by the play system to display videos The device displays 30Hz, 60Hz, or 120Hz or other screen display cycles according to each other.

At this time, each of the multi-display systems transmits and receives information about clock correction to the network from a system using a master clock as a reference, so that each system is aligned with the reference synchronization. Usually, the prior art provides sophisticated media playback timing by synchronizing with PTP (Precision Time Protocol) and utilizing this PTP information.

However, when used in an actual system, if the network becomes unavailable while the PTP is operating, the synchronization clock function in the display system may not operate or the synchronized portion may be distorted.

In this case, since the screens displayed between the multi-display screens are distorted, there is a problem in displaying the entire screen, and a method for solving this problem is requested.

The present invention was conceived to solve the above problems, and an object of the present invention is to further operate a sub-clock in addition to the network-based main-clock in expressing images on a plurality of displays. An object of the present invention is to provide an image reproducing apparatus capable of maintaining precise image reproducing time synchronization even when a problem occurs.

According to an embodiment of the present invention for achieving the above object, an image reproducing apparatus includes: a player for reproducing one of images to be displayed on each of a plurality of displays; A first clock system providing a first clock; A second clock system providing a second clock; And a synchronization system for synchronizing an image reproduction time of a player with image reproduction times of other players using a first clock provided by the first clock system and a second clock provided by the second clock system.

In addition, the first clock system may obtain a first clock provided from an external network and provide it to the synchronization system.

Also, the second clock system can generate the second clock internally.

Further, the stability of the first clock may be higher than that of the second clock.

Further, the synchronization system may provide the first clock to the reproducer if the first clock is provided by the first clock system.

Further, the synchronization system may provide the second clock to the regenerator if the first clock is not provided by the first clock system.

Further, the synchronization system can provide the second clock to the regenerator when the first clock provided by the first clock system does not match the time transition.

And, the synchronization system can provide the second clock to other players.

Further, the second clock system includes: a receiver for receiving a first clock from the first clock system; A clock generator for generating an internal clock; An analyzer that compares the first clock with the internal clock and corrects the internal clock; And an output device that outputs the corrected internal clock as a second clock.

On the other hand, according to another embodiment of the present invention, an image reproducing method includes: a Din-gye for reproducing one of images to be displayed on each of a plurality of displays; And synchronizing the image reproduction time with image reproduction times of other players using a first clock provided by the first clock system and a second clock provided by the second clock system.

Meanwhile, according to another embodiment of the present invention, an image display system includes: a player for reproducing one of images to be displayed on each of a plurality of displays; A display that displays an image reproduced in a player; A first clock system providing a first clock; A second clock system providing a second clock; And a synchronization system for synchronizing the image reproduction time of the player with the image reproduction times of other players using the first clock obtained by the first clock system and the second clock generated by the second clock system.

On the other hand, according to another embodiment of the present invention, an image display method may include: Din-gye for reproducing one of the images to be displayed on each of a plurality of displays; Displaying the reproduced image; And synchronizing the image reproduction time with image reproduction times of other players using a first clock provided by the first clock system and a second clock provided by the second clock system.

As described above, according to the embodiments of the present invention, even when a problem occurs in the network-based main-clock, video playback synchronization through multi-display and super-multi-view display is performed using an internally generated sub-clock. It can be kept precisely.

In addition, according to embodiments of the present invention, by correcting the sub-clock by analyzing the network-based main-clock, a sub-clock close to the main-clock is generated and prepared, thereby synchronizing high-precision video playback time without the main-clock. Becomes possible.

1 is a diagram showing a multi-display system to which the present invention is applicable;
2 is a block diagram of an image reproducing apparatus according to an embodiment of the present invention;
3 is a detailed block diagram of the SACS shown in FIG. 2, and,
4 is a diagram showing a difference in speed between a PTP clock and an internal clock.

Hereinafter, the present invention will be described in more detail with reference to the drawings.

1. Display system

1 is a diagram showing a display system to which the present invention is applicable. The illustrated display system can be implemented as a multi-display system, an ultra-multi-view display system, or the like.

In addition, FIG. 1 shows the concept of time synchronization between devices through PTP. A multi-display system to which the present invention can be applied is based on IEEE 1588 Precision Time Protocol (PTP) or IEEE 802.1AS standards in an Ethernet network environment.

It is based on the basic premise that all end-point devices that display super multi-view images are synchronized with a source source that provides the same time, that is, a Grandmaster.

For such time synchronization, each terminal must support PTP, and each terminal must be connected to the network through an Ethernet switch supporting PTP. Terminals synchronized with PTP can be precisely synchronized to microseconds or nanoseconds.

Therefore, the time of the clocks used by all the terminals of the network that has been synchronized with the PTP is almost exactly the same.

2. Video playback device

2 is a block diagram of an image reproducing apparatus according to an embodiment of the present invention. A video reproducing apparatus according to an embodiment of the present invention uses a network-based PTP clock as a main-clock and operates an internal clock as a sub-clock.

Specifically, when a problem occurs in using the PTP clock, which is a main-clock, in the video reproducing apparatus according to an embodiment of the present invention, the video reproducing apparatus is synchronized with other video reproducing apparatuses using the sub-clock to display an image. Make sure there are no problems with motivation.

In addition, the video reproducing apparatus according to an embodiment of the present invention corrects the sub-clock using the PTP clock, which is the main-clock, so that the sub-clock matches the main-clock as much as possible.

An image reproducing apparatus according to an embodiment of the present invention performing such a function includes a player 110, a PTP Clock System (PCS) 120, a Clock Comparator System (CCS) 130, as shown in FIG. 2. And a Synchronization Assistant Clock System (SACS) 140.

The player 110 receives and reproduces the image, and displays the reproduced image through a display (not shown).

The image reproduced by the player 110 is an image for multi-display or ultra-multi-view display, and corresponds to one of images to be displayed on each of a plurality of displays, and is a multi-screen or super-multi-view image together with other image reproducing devices. Configure.

The PCS 120 receives and obtains a PTP clock from a network switch (an Ethernet switch supporting PTP), and provides the obtained PTP clock to the CCS 130 and SACS 140. The PTP clock functions as the main-clock.

The SACS 140 generates a Synchronization Assistant Clock (SAC) functioning as an auxiliary-clock using the internal clock of the system, and provides the generated SAC to the CCS 130.

A detailed structure of the SACS 140 and a method of generating the SAC by the SACS 140 will be described in detail later.

The CCS 130 uses the PTP clock provided from the PCS 120 and the SAC provided from the SACS 140 to determine the video playback time of the player 110 and the video playback times of players provided in other video playback devices. It is a synchronization system that synchronizes.

In order to prevent a problem with video synchronization even when a problem/abnormal situation occurs, the CCS 130 performs the following functions.

1) When the PTP clock is provided from the PCS 120, the CCS 130 transmits the PTP clock to the player 110, so that the video playback time is synchronized by the PTP clock.

2) If the PTP clock is not provided from the PCS 120, the CCS 130 transmits the SAC provided from the SACS 140 to the player 110, so that the video playback time is synchronized by the SAC.

3) Although the PTP clock is provided from the PCS 120, even if the PTP clock does not match the time trend, the CCS 130 transmits the SAC provided from the SACS 140 to the player 110, and SAC Synchronization of the video playback time is achieved by

Whether or not the time trend is met can be determined by comparing the PTP clock and the SAC. If the time difference is irregular as a result of the comparison between the two, it can be determined that the PTP clock does not match the time trend.

4) When a situation of "2)" or "3)" occurs, the PCS 120 sends a multi-view video or a multi-view video from the SACS 140 together with the video playback device to other video playback devices in the vicinity. Provided SAC can be provided.

3. Synchronization Assistant Clock System (SACS)

Hereinafter, the SACS 140 will be described in detail with reference to FIG. 3. 3 is a detailed block diagram of the SACS 140 shown in FIG. 2. The SACS 140, as shown in FIG. 3, includes an output unit 141, an analysis unit 142, a reception unit 143, and an internal clock generation unit 144.

The receiving unit 143 receives the PTP clock from the PCS 120 and transmits the received PTP clock to the analysis unit 142.

The internal clock generation unit 144 generates an internal clock using an oscillator provided inside the system, and transmits the generated internal clock to the analysis unit 142.

The analysis unit 142 analyzes the PTP clock received through the reception unit 143 and corrects the internal clock generated by the internal clock generation unit 144. Unlike the PTP clock, the internal clock generated by the internal clock generator 144 is unstable and needs to be corrected.

That is, as shown in FIG. 4, the PTP clock received through the receiving unit 143 generally provides synchronization information without shaking, while the internal clock generation unit 144 is generated in a computing environment in which various processes are executed. The internal clock is shaken, and there is a difference in clock speed between the two.

Accordingly, the analysis unit 142 detects this difference and continues the process of calculating and correcting ΔT between the PTP clock and the internal clock during the operating time of the internal clock generation unit 144.

The output unit 141 outputs the internal clock corrected by the analysis unit 142 to the CCS 130 as SAC.

Up to now, a preferred embodiment has been described in detail for a multi-display system having a network-based synchronous auxiliary clock.

In an embodiment of the present invention, by operating a sub-clock in a system for displaying images on a plurality of displays, precise time synchronization for image playback/display is maintained even when the network-based PTP clock is stopped.

The technical idea of the present invention can be applied not only to an image reproducing apparatus that reproduces an image and transmits it to a display, but also to an image display system that displays an image including a display.

Meanwhile, it goes without saying that the technical idea of the present invention can be applied to a computer-readable recording medium containing a computer program for performing functions of the apparatus and method according to the present embodiment. Further, the technical idea according to various embodiments of the present invention may be implemented in the form of a computer-readable code recorded on a computer-readable recording medium. The computer-readable recording medium can be any data storage device that can be read by a computer and can store data. For example, a computer-readable recording medium may be a ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical disk, hard disk drive, or the like. In addition, a computer-readable code or program stored in a computer-readable recording medium may be transmitted through a network connected between computers.

In addition, although the preferred embodiments of the present invention have been illustrated and described above, the present invention is not limited to the specific embodiments described above, and the technical field to which the present invention belongs without departing from the gist of the present invention claimed in the claims. In addition, various modifications are possible by those of ordinary skill in the art, and these modifications should not be understood individually from the technical spirit or prospect of the present invention.

110: player 120: PCS (PTP Clock System)
130: CCS (Clock Comparator System)
140: Synchronize Assistant Clock System (SACS)
141: output unit 142: analysis unit
143: receiver 144: internal clock generator

Claims (12)

A player reproducing one of the images to be displayed on each of the plurality of displays;
A first clock system providing a first clock;
A second clock system providing a second clock;
Including; a synchronization system for synchronizing the video playback time of the player with the video playback times of other players by using the first clock provided by the first clock system and the second clock provided by the second clock system,
Synchronization system,
If the first clock is provided in the first clock system, it provides the first clock to the regenerator,
If the first clock is not provided in the first clock system, a second clock is provided to the regenerator,
When the first clock provided by the first clock system does not match the time change, a second clock is provided to the player.
The method according to claim 1,
The first clock system,
An image reproducing apparatus, comprising acquiring a first clock provided from an external network and providing it to a synchronization system.
The method according to claim 1,
The second clock system,
An image reproducing apparatus comprising internally generating a second clock.
The method according to claim 1,
The stability of the first clock is,
A video reproducing apparatus, characterized in that it is higher than the stability of the second clock.
delete delete delete A player reproducing one of the images to be displayed on each of the plurality of displays;
A first clock system providing a first clock;
A second clock system providing a second clock;
Including; a synchronization system for synchronizing the video playback time of the player with the video playback times of other players by using the first clock provided by the first clock system and the second clock provided by the second clock system,
Synchronization system,
If the first clock is provided in the first clock system, it provides the first clock to the regenerator,
An image reproducing apparatus comprising providing a second clock to other players.
The method according to claim 1,
The second clock system,
A receiver for receiving a first clock from a first clock system;
A clock generator for generating an internal clock;
An analyzer that compares the first clock with the internal clock and corrects the internal clock; And
And an output unit that outputs the corrected internal clock as a second clock.
Din-gye, the player reproducing one of the images to be displayed on each of the plurality of displays;
Synchronizing, by the synchronization system, an image reproduction time with image reproduction times of other players using a first clock provided by the first clock system and a second clock provided by the second clock system,
The synchronization step is,
If the first clock is provided in the first clock system, it provides the first clock to the regenerator,
If the first clock is not provided in the first clock system, a second clock is provided to the regenerator,
When the first clock provided by the first clock system does not match the time change, a second clock is provided to the player.
A player reproducing one of the images to be displayed on each of the plurality of displays;
A display for displaying an image reproduced by the player;
A first clock system providing a first clock;
A second clock system providing a second clock;
Including; a synchronization system for synchronizing the image reproduction time of the player with the image reproduction times of other players using the first clock obtained from the first clock system and the second clock generated from the second clock system,
Synchronization system,
If the first clock is provided in the first clock system, it provides the first clock to the regenerator,
If the first clock is not provided in the first clock system, provide a second clock to the regenerator,
When the first clock provided by the first clock system does not match the time change, a second clock is provided to the player.
Din-gye, the player reproducing one of the images to be displayed on each of the plurality of displays;
Displaying, by the display, the reproduced image;
Synchronizing, by the synchronization system, an image reproduction time with image reproduction times of other players using a first clock provided by the first clock system and a second clock provided by the second clock system,
The synchronization step is:
If the first clock is provided in the first clock system, it provides the first clock to the regenerator,
If the first clock is not provided in the first clock system, provide a second clock to the regenerator,
When the first clock provided by the first clock system does not match the time change, a second clock is provided to the player.

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