KR101116071B1 - Broadcasting system for integrated controlling of mixed audio video signal using serial digital interface and method thereof - Google Patents

Abstract

PURPOSE: A centralized SDI broadcasting system and method thereof are provided to reduce maintenance costs by improving the convenience of a system facility and by accepting the bandwidth of all signals. CONSTITUTION: An input interface module(210) changes AV(Audio and Video) signals inputted by signal input terminals into SDI(Serial Digital Interface) signals including an SDI standard format. A matrix router module(220) establishes an input and output route for the SDI signal. An output interface module(230) transmits the SDI signal to an external apparatus corresponding to the input and output route.

Description

Centralized SD broadcasting system for integrated control of mixed AV signal and its method {BROADCASTING SYSTEM FOR INTEGRATED CONTROLLING OF MIXED AUDIO VIDEO SIGNAL USING SERIAL DIGITAL INTERFACE AND METHOD THEREOF}

Embodiments of the present invention relate to an SDI broadcasting system and a method for transmitting audio / video (AV) signals of various formats through a centralized integrated control by unifying signal specifications.

The current AV signal is composed of a low-grade SD composite analog signal and a high-definition digital video signal due to the digital conversion transition.

In other words, the interface method of audio and video signals is composed of various formats such as composite, component, S-video, video graphics array (VGA), digital video interactive (DVI), high definition multimedia interface (HDMI), and optics. .

Therefore, a signal system must be unified in a signal transmission process and an editing process to construct a system for broadcasting, and furthermore, a digital broadcasting system can be constructed only when centralized control is possible.

Provided are an SDI broadcasting system and a method for unifying signal specifications for various formats of AV signals and for transmitting AV signals through centralized integrated control.

Provided are a SDI broadcasting system and a method for unifying a signal standard as a serial digital interface (SDI) in a signal transmission process by accommodating a bandwidth of all signals and configuring a central SDI matrix for integrated control of various AV signals.

An input interface module for converting an AV (audio / video) signal input from a plurality of signal input terminals having different interface methods into an SDI signal having a format of a serial digital interface (SDI) standard; A matrix router module configured to set an input / output path for an SDI signal; And an output interface module for transmitting an SDI signal to an external device corresponding to an input / output path.

According to one side, the input interface module is at least one of an analog to digital converter, high-definition up converter, high-definition down converter, media converter (media converter) It may be configured to include.

According to another aspect, the input interface module may insert attribute information of the AV signal into metadata in the auxiliary data section of the SDI signal.

According to another aspect, the matrix router module has an amplitude characteristic, a rising time characteristic, a falling time characteristic, a rising / falling time difference characteristic, a waveform overshoot, Signal stability of the signal input terminal may be verified through at least one measurement item among an overshoot characteristic, a DC offset characteristic, and a jitter characteristic.

According to another aspect, the matrix router module may verify the SDI signal using at least one of a cyclic redundancy check (CRC) function and an error detection handling (EDH) function based on the SDI standard.

According to another aspect, the output interface module may convert the SDI signal into a format supported by the external device, or convert the format of the SDI signal in response to a transmission network providing a transmission path to the external device.

A broadcast transmission method of a digital broadcasting system for transmitting a broadcast signal, the broadcast transmission method comprising: converting an AV signal input from a plurality of signal input terminals having different interface methods into an SDI signal having an SDI format; Setting an input / output path for the SDI signal; And transmitting an SDI signal to an external device corresponding to an input / output path.

By converting the AV signal of various formats into the SDI standard, which is robust for signal transmission, during signal transmission and editing for broadcasting, degradation of the original signal can be minimized during signal transmission, and various information can be inserted in addition to the signal. Moreover, it is easy to establish digital broadcasting environment while maintaining existing analog broadcasting facilities.

In addition, it is possible to improve the convenience of the system facilities by accommodating the bandwidth of all signals, it is possible to economically install the system construction compared to other methods in the short-distance transmission, and easy maintenance and signal checking by step.

In addition, since the signal control of various formats of AV signals is performed in a central matrix, efficient centralized control is possible in constructing a digital broadcasting system.

1 is a diagram illustrating a digital broadcast system for integrated control of AV signals in various formats according to an embodiment of the present invention.
2 is a block diagram illustrating an internal configuration of an SDI broadcast system using an SDI standard for transmitting broadcast signals according to an embodiment of the present invention.
3 is a diagram for describing a process of converting a YCbCr video signal into a SDI standard format according to an embodiment of the present invention.
4 is a diagram for describing SDI measurement items for verifying signal stability according to an embodiment of the present invention.
5 is a flowchart illustrating a broadcast transmission method of an SDI broadcast system for transmitting a broadcast signal according to the SDI standard according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram illustrating a digital broadcast system for integrated control of AV signals in various formats according to an embodiment of the present invention. FIG. 1 illustrates a digital broadcasting system 120 (hereinafter, referred to as an "SDI broadcasting system") using the SDI standard for transmitting broadcast signals.

The SDI broadcasting system 120 according to an embodiment unifies the interface method of the AV signal provided from the input device 110 to the SDI standard to perform signal transmission and editing for broadcasting.

Here, the input device 110 may mean any device capable of generating or storing an AV signal such as a DVD, a camera, a PC, a recorder, and the like. The AV signals provided from the various input devices 110 may be configured in various formats such as CVBS, Component, S-Video, VGA, DVI, HDMI, SDI, Optic, and the like.

Therefore, in the present embodiment, a system for unifying the AV signals of various formats provided by the input device 110 into the SDI standard and transmitting them to the output device 130 is constructed. In this case, the output device 130 may refer to a transmission device for transmitting a broadcast signal in association with a broadcasting facility, a storage means for storing the broadcast signal, a server system for maintaining and managing the broadcast signal, a display means for outputting the broadcast signal, and the like. The kind is not limited thereto. For example, the output device 130 may be an encoder, a recorder, a server, a monitor, or the like. Most of the output equipment 130 for broadcasting is configured based on the SDI standard it is easy to link with the SDI broadcasting system 120.

SDI is an international protocol for transmitting digital AV signals. Unlike parallel data transmission, SDI can simplify cable signals. Most broadcast signals of broadcasting stations use SDI signals. In this case, SDI also supports protocols for error signals that may occur during transmission. The SDI may use a general coaxial 75 ohm cable, and the data rate may cover up to 3G bands. In addition, SDI can insert various additional data and can accommodate an audio signal.

Referring to Figure 2, the configuration and operation of the SDI broadcast system using the SDI standard for the transmission of broadcast signals will be described in detail.

2 is a block diagram showing an internal configuration of an SDI broadcasting system according to an embodiment of the present invention. As shown in FIG. 2, the SDI broadcasting system 200 according to an embodiment may be configured with an input interface module 210, a matrix router module 220, and an output interface module 230.

The input interface module 210 may convert an AV signal input from a plurality of signal input terminals having different interface methods into a format of an SDI standard. That is, the input interface module 210 is configured as a mixed signal input interface structure and serves to convert an SDI signal, which is a standard interface output for various signals. Here, the mixed signal may be regarded as a combination of all AV signals that are currently used, and in other words, it may be regarded as a complex configuration of all signals that are currently used, such as analog, digital, and optical signals. For example, a DVD or camera signal is composed of a general composite signal, and a recorder or a PC is mixed with digital signals to form a mixed signal structure. The input interface module 210 includes at least one of an analog-to-digital converter, a high-definition up converter, a high-definition down converter, and a media converter. Can be. In this case, the A / D converter may mean a means for converting an analog signal of a video signal, that is, a composite, component signal, which is a TV analog signal that is generally used, into a digital broadcast signal. In addition, the HD up-converter may mean a means for converting the resolution of the AV signal of the SD class resolution to the HD level, and the HD down converter may mean a means for converting the resolution of the AV signal of the HD level resolution to the SD class. In addition, the media converter may mean a means for converting a video audio signal such as a DVD, set-top box, PC, etc. into a signal of another format, that is, a digital signal. For example, the input interface module 210 includes an A / D converter and a parallel to serial converter, as shown in FIG. 3, to color the YCbCr image signal when the luminance signal Y is sampled four times. (CbCr) can be sampled twice, and its format can be converted into an image signal in which Y: Cb: Cr is 4: 2: 2. Accordingly, the input interface module 210 may convert all AV signals into SDI signals using the above means (A / D converter, HD up converter, HD down converter, media converter, etc.). In addition, since the additional data may be inserted in the SDI format, the input interface module 210 may insert attribute information of various AV signals as metadata in an auxiliary data section of the SDI signal.

The matrix router module 220 serves as a central router for setting the input / output path of the SDI signal changed in the input interface module 210 without deterioration of the signal through digital signal routing. For example, in the SDI broadcasting system 200, if the signal input terminal is 1 to 16 and the signal output terminal is 1 to 16, the matrix router module 220 may have 1 to 16 signal output terminals 1 to 16 for each signal output terminal. Which of the 16 signal input stages is used to determine the signal transmission path of the signal input stage. When the signal input terminal 1 is a camera signal, the signal transmission path for the signal output terminal 1 should be set to the signal input terminal 1 in order to transmit the camera signal to the signal output terminal 1. That is, the matrix router module 220 may freely change a signal transmission path according to an input / output path.

In addition, the matrix router module 220 determines the signal stability of the signal input terminal based on the SDI standard. Since the stability of the signal is verified for each block constituting the SDI broadcasting system 200, the entire system maintains stability, and therefore, the signal specification at the signal input terminal must be checked for this purpose. In this embodiment, since the SDI format is used, the stability of the signal is also verified based on the SDI signal. As shown in Fig. 4, the signal stability criteria for the SDI signal are standardized and determined in advance, and the stability of the signal is recognized when the standards are met (for example, SMPTE259M and SMPTE292M). When the above-mentioned SDI standard is satisfied, there is no problem in transmitting and receiving signals when using a BNC cable (coaxial cable) within 100m when constructing a system. On the contrary, when the corresponding standard is not satisfied, a signal problem may occur, such as a flickering screen or a short line. That is, the matrix router module 220 analyzes eye patterns, amplitude characteristics, rising time characteristics, falling time characteristics, and falling / falling time differences with respect to signals at the signal input terminal based on the SDI standard. The stability of the signal may be determined by checking each measurement item such as a characteristic, an overshoot characteristic of a waveform, a DC offset characteristic, and a jitter characteristic. In this case, the matrix router module 220 may internally compensate for an unstable signal within a predetermined range. For example, the matrix router module 220 may perform signal compensation by using a cable equalizer that compensates for a signal level according to a cable length, a click-reclock device that compensates for a clock error due to a phase error, and the like. If the signal stability is not guaranteed despite the compensation described above, the matrix router module 220 may report the corresponding error state to guide the user to directly check the input signal. In addition, since SDI also supports protocols for error signals that may occur when transmitting signals, the matrix router module 220 may include at least one of a cyclic redundancy check (CRC) function and an error detection handling (EDH) function based on the SDI standard. Can be used to verify data reliability in serial transmission. That is, in the present embodiment, it is easy to secure and check the signal stability by using the SDI format.

The output interface module 230 may transmit an SDI signal to external equipment (that is, the output equipment disclosed in the related description of FIGS. 1 and 1) according to the input / output path set by the matrix router module 220. In other words, the output interface module 230 performs output signal matching, timing matching, and transmission network conversion for interworking with external equipment. In this case, since the output signal from the matrix router module 220 may be a signal of the SDI format or a format different from that of the SDI in the external equipment, the output interface module 230 may be used for signal matching and matching with respect to the external equipment. SDI signals can be converted to a format supported by external equipment. In addition, the output interface module 230 may perform a series of processes for matching synchronization with an external device when a timing change for interworking with an external device such as a delay compensation or an audio / video lip sync problem is required. In addition, in order to transmit a broadcast signal, a signal is transmitted to a broadcasting network through a transmission to a head-end. In the case of a broadcasting station, a signal is transmitted from a transmitting station in a radio wave. Will be sent. That is, the output interface module 230 may convert the format of the SDI signal in response to a transmission network (ie, a broadcasting network) that provides a transmission path to external equipment for signal transmission. In this case, for most signal transmission, the data rate is reduced by signal compression through compression multiplexing. For this purpose, an MPEG encoder may be connected to the SDI broadcasting system 200. In other words, the SDI broadcasting system 200 converts an SDI signal into a format such as MPEG-2 or H.264 through an MPEG encoder and transmits it to an external device. Since a general encoder receives an SDI format signal as an input, the SDI broadcasting system 200 can link to an MPEG encoder without changing a special signal.

According to the above configuration, the SDI broadcasting system 200 can establish a digital broadcasting environment while maintaining the existing analog broadcasting facilities, and it is possible to construct an economical system in comparison with other methods for short-distance transmission, so that it is a small private broadcasting facility and an end broadcasting facility. It can be applied to school or academy broadcasting facility, in-house broadcasting facility, government broadcasting facility, factory disaster prevention facility, security camera facility, remote monitoring facility, and the like.

5 is a flowchart illustrating a broadcast transmission method of an SDI broadcast system for transmitting a broadcast signal according to the SDI standard according to an embodiment of the present invention. In the broadcast transmission method according to the present embodiment, each step may be performed by the SDI broadcast system 200 described with reference to FIG. 2.

In operation 510, the SDI broadcasting system 200 converts an AV signal input from a plurality of signal input terminals having different interface types into a SDI standard format. In this case, the SDI broadcasting system 200 uses the configuration of the A / D converter, the HD up converter, the HD down converter, the media converter, and the like, when the luminance signal Y is sampled four times, the color signal CbCr. Is sampled twice and Y: Cb: Cr is a 4: 2: 2 video signal that can be converted into the SDI format. In addition, since the additional data may be inserted in the SDI format, the SDI broadcasting system 200 may insert attribute information of various AV signals as metadata in an auxiliary data section of the SDI signal.

In operation 520, the SDI broadcasting system 200 sets an input / output path of the SDI signal changed in operation 510 through digital signal routing. That is, the SDI broadcasting system 200 may set a transmission path of which signal input terminal to output a signal for each signal output terminal. In addition, the SDI broadcasting system 200 may determine the signal stability of the signal input terminal based on the SDI standard before setting the input / output path for the SDI signal. In detail, the SDI broadcasting system 200 performs eye pattern analysis, amplitude characteristics, rising time characteristics, polling time characteristics, rising / falling time difference characteristics, waveform overshoot characteristics, DC, and the like at a signal input terminal based on the SDI standard. It is possible to determine whether the signal is stable by checking each measurement item such as an offset characteristic and a jitter characteristic. In addition, the SDI broadcasting system 200 may verify data reliability of the SDI signal using at least one of a CRC function and an EDH function based on the SDI standard.

In operation 530, the SDI broadcasting system 200 transmits an SDI signal to external equipment corresponding to the input / output path set in operation 520. In other words, the SDI broadcasting system 200 converts the SDI signal into a format supported by the external device for signal matching and matching with respect to the external device, or formats the SDI signal in response to a transmission network providing a transmission path to the external device. Can be converted. In this case, the SDI broadcast system 200 may perform timing matching to match synchronization with an external device when it is necessary to change a timing for interworking with an external device. In addition, the SDI broadcasting system 200 transmits after adjusting the data rate through signal compression through compression multiplexing. For this purpose, the SDI broadcasting system 200 converts an SDI signal into a format such as MPEG-2 or H.264 through an MPEG encoder. It can be sent to external equipment.

As described above, according to embodiments of the present invention, deterioration of an original signal may be minimized during signal transmission by converting an AV signal of various formats into an SDI standard that is strong for signal transmission in a signal transmission process and an editing process for broadcasting. In addition, by constructing a broadcasting system using the SDI standard, it is possible to accommodate the bandwidth of all signals, and it is easy to establish a digital broadcasting environment while maintaining an existing analog broadcasting facility. The broadcasting system having the above-described configuration can be economically installed in the system construction in contrast to other methods for short-range transmission. In addition, since the signal control for various formats of AV signals is performed in a central matrix, there is an advantage that efficient centralized control is possible in constructing a digital broadcasting system.

As described above, the present invention has been described by way of limited embodiments and drawings, but the present invention is not limited to the above embodiments, and those skilled in the art to which the present invention pertains various modifications and variations from such descriptions. This is possible.

Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined not only by the claims below but also by the equivalents of the claims.

200: SDI broadcasting system
210: input interface module
220: matrix router module
230: output interface module

Claims (10)

In a digital broadcasting system for transmitting a broadcast signal,
An input interface module for converting an AV (audio / video) signal input from a plurality of signal input terminals having different interface methods into an SDI signal having a format of a serial digital interface (SDI) standard;
A matrix router module configured to set an input / output path for the SDI signal; And
An output interface module for transmitting the SDI signal to an external device corresponding to the input / output path
Including,
The plurality of signal input terminals,
The interface method is CVBS (Composite Video Blanking Sync), Component, S (Super) -Video, VGA (Video Graphic Array), DVI (Digital Video Interface), HDMI (High-Definition Multimedia Interface), SDI (serial digital) consisting of at least one of an interface and an optical interface
Digital broadcasting system characterized in that. The method of claim 1,
The input interface module,
Comprising at least one of an analog-to-digital converter, a high-definition up converter, a high-definition down converter, and a media converter
Digital broadcasting system characterized in that. The method of claim 1,
The input interface module,
Inserting attribute information of the AV signal into metadata in an auxiliary data section of the SDI signal;
Digital broadcasting system characterized in that. The method of claim 1,
The matrix router module,
An amplitude characteristic, a rising time characteristic, a falling time characteristic, a rising / falling time difference characteristic, a waveform overshoot characteristic, a DC offset characteristic, Verifying the signal stability of the signal input through at least one measurement item of jitter characteristics
Digital broadcasting system characterized in that. The method of claim 1,
The matrix router module,
Verifying the SDI signal using at least one of a cyclic redundancy check (CRC) function and an error detection handling (EDH) function based on the SDI standard;
Digital broadcasting system characterized in that. The method of claim 1,
The output interface module,
Converting the SDI signal into a format supported by the external device, or converting the format of the SDI signal in response to a transmission network providing a transmission path to the external device;
Digital broadcasting system characterized in that. In the broadcast transmission method of a digital broadcast system for transmitting a broadcast signal,
Converting an AV signal input from a plurality of signal input terminals having different interface types into an SDI signal having a format of an SDI standard;
Setting an input / output path for the SDI signal; And
Transmitting the SDI signal to an external device corresponding to the input / output path;
Including,
The plurality of signal input terminals,
The interface method is CVBS (Composite Video Blanking Sync), Component, S (Super) -Video, VGA (Video Graphic Array), DVI (Digital Video Interface), HDMI (High-Definition Multimedia Interface), SDI (serial digital) consisting of at least one of an interface and an optical interface
Broadcast transmission method characterized in that. The method of claim 7, wherein
The broadcast transmission method,
Verifying signal stability of the signal input terminal before setting the input / output path;
Further comprising:
Verifying the signal stability of the signal input terminal,
Based on the SDI standard, at least one measurement item among an amplitude characteristic, a rising time characteristic, a polling time characteristic, a rising / falling time difference characteristic, a waveform overshoot characteristic, a DC offset characteristic, and a jitter characteristic may be measured. Verifying the signal stability of the signal input terminal through
Broadcast transmission method characterized in that. The method of claim 7, wherein
The broadcast transmission method,
Verifying signal stability of the signal input terminal before setting the input / output path;
Further comprising:
Verifying the signal stability of the signal input terminal,
Verifying the SDI signal using at least one of a CRC function and an EDH function based on the SDI standard;
Broadcast transmission method characterized in that. The method of claim 7, wherein
The step of transmitting the SDI signal,
Converting the SDI signal into a format supported by the external device, or converting the format of the SDI signal in response to a transmission network providing a transmission path to the external device;
Broadcast transmission method characterized in that.

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