KR20190134318A - Method and apparatus for providing a digital broadcast closed caption service - Google Patents

Abstract

Disclosed is a method of providing a digital broadcast closed captioning service. According to an embodiment of the present invention, a method of providing a digital broadcast closed captioning service comprises the steps of: receiving digital broadcast closed caption data; and displaying a caption in a caption window based on the digital broadcast closed caption data. The digital broadcast closed caption data includes a code space control, a caption command, and caption characters. The caption command may include at least one among a karaoke function, an outline function, a scale function, a rotation function, and a move function.

Description

METHOD AND APPARATUS FOR PROVIDING A DIGITAL BROADCAST CLOSED CAPTION SERVICE}

The present invention relates to a method and apparatus for providing a closed digital captioning service, and more particularly, to a method and apparatus for providing a closed captioning service for providing a caption broadcasting service that extends a caption command of the CEA-708 standard. It is about.

Starting with high definition (HD) broadcasting service with the conversion of domestic terrestrial digital broadcasting, ultra high definition (Ultra HD, UHD) broadcasting service began to be provided in the metropolitan area in 2017. Such high-definition video and audio will allow ordinary viewers to experience higher realism and realism. However, the development of this technology will not be seen as a better broadcast service for the hearing impaired, foreigners, etc. that can only accept the image.

Closed caption is a very important service for hearing impaired people who can get information through broadcasting to close the social information gap. At present, domestic terrestrial broadcasters provide almost 100% of closed captioning services through real-time shorthand as part of this social effort. Nevertheless, many deaf people continue to complain about current closed captioning services. This is due to the characteristics of the real-time shorthand caption service system inevitably delays and misspelling of the caption, and is a problem caused by transferring the speech provided by the shorthand as captions without considering the low sentence comprehension of the hearing impaired.

An object of the present invention is to provide an extended caption command control code based on the existing standard caption (CEA-708).

In addition, the technical problem of the present invention is to provide a better subtitle service by providing the subtitle command control code provided to viewers while maintaining backward compatibility with existing digital broadcasting subtitle services.

Technical problems to be achieved in the present invention are not limited to the above-mentioned technical problems, and other technical problems not mentioned above will be clearly understood by those skilled in the art from the following description. Could be.

According to an aspect of the present invention, a method for providing closed digital closed caption service includes receiving digital closed caption data and displaying the closed caption in a caption window based on the received digital closed caption data. The digital broadcasting closed caption data may include a code space control, a caption command, and a caption character, and the caption command may include at least one of a KARAOKE function, an OUTLINE function, a SCALE function, a ROTATION function, and a MOVE function.

In the method of providing a closed captioning service for digital broadcasting, at least one caption command among the KARAOKE function, the OUTLINE function, the SCALE function, the ROTATION function, and the MOVE function may be included in an extended code set (C2 code set).

In the digital broadcasting closed captioning service providing method, the KARAOKE function may be a caption command having a function of changing a color of a character or a background with a character string of the caption.

In the digital broadcasting closed caption service providing method, the OUTLINE function may be a caption command having a function of displaying a color, size, and shadow of an outline of a caption.

In the digital broadcasting closed captioning service providing method, the SCALING function may be a caption command of a function of adjusting the flatness of a character font of the caption.

In the digital broadcasting closed caption service providing method, the ROTATION function may be a caption command of a function of rotating a character of the caption.

In the method of providing a closed digital captioning service, the MOVE function may be a caption command of a function of moving a caption character to a predetermined position.

The features briefly summarized above with respect to the present invention are merely exemplary aspects of the detailed description of the present disclosure described below, and do not limit the scope of the present disclosure.

According to the present invention, by extending a new subtitle command based on the existing subtitle standard (CEA-708), it is possible to maintain backward compatibility with existing digital broadcasts, thereby extending only the decoder without modifying the signaling for the current subtitle transmission. This has the advantage of being able to work on existing systems.

According to the present invention, by providing a three-dimensional subtitle-like expression in the current two-dimensional text-centric subtitle environment can provide a useful service not only for the disabled but also for the disabled (elderly, infants, foreigners, etc.). There is an advantage.

The effects obtainable in the present invention are not limited to the above-mentioned effects, and other effects not mentioned above may be clearly understood by those skilled in the art from the following description. will be.

1 illustrates a digital broadcast 16: 9 screen and a DTVCC window.
2 is a diagram illustrating a digital broadcast bitstream structure.
3 is a diagram for explaining an example of a digital broadcasting subtitle.
4 is a diagram for explaining an example of a DTVCC code set.
5 is a diagram for explaining an example of a C1 codeset.
6 is a diagram for describing a caption command according to an exemplary embodiment.
7 is a flowchart illustrating a method for providing a closed digital captioning service according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present disclosure. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

In the following description of embodiments of the present disclosure, when it is determined that a detailed description of a known structure or function may obscure the subject matter of the present disclosure, a detailed description thereof will be omitted. In the drawings, parts irrelevant to the description of the present disclosure are omitted, and like reference numerals designate like parts.

In the present disclosure, when a component is "connected", "coupled" or "connected" with another component, it is not only a direct connection, but also an indirect connection in which another component exists in the middle. It may also include. In addition, when a component "includes" or "having" another component, it means that it may further include another component, without excluding the other component unless otherwise stated. .

In the present disclosure, terms such as first and second are used only for the purpose of distinguishing one component from other components, and do not limit the order or importance between the components unless specifically mentioned. Accordingly, within the scope of the present disclosure, a first component in one embodiment may be referred to as a second component in another embodiment, and likewise, a second component in one embodiment may be referred to as a first component in another embodiment. It may also be called.

In the present disclosure, components that are distinguished from each other are for clearly describing each feature, and do not necessarily mean that the components are separated. That is, a plurality of components may be integrated into one hardware or software unit, or one component may be distributed and formed into a plurality of hardware or software units. Therefore, even if not mentioned otherwise, such integrated or distributed embodiments are included in the scope of the present disclosure.

In the present disclosure, components described in various embodiments are not necessarily required components, and some may be optional components. Therefore, an embodiment composed of a subset of components described in an embodiment is also included in the scope of the present disclosure. In addition, embodiments including other components in addition to the components described in the various embodiments are included in the scope of the present disclosure.

Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings.

1 is a diagram illustrating a digital broadcast 16: 9 screen and a DTVCC (DTV Closed Caption) window.

Referring to FIG. 1, a caption may be provided in a caption window within a DTVCC screen in a safe-image area of a digital broadcasting screen.

The current closed captions of domestic digital broadcasts are being transmitted based on the CEA-708 series standard specification in North America. In the CEA-708 standard, subtitles may be provided in a subtitle window as shown in FIG. 1.

The CEA-708 standard specifies subtitle windows and subtitle sizes, colors, alignments, orientations, borders, and performance recommendations for decoders.

The CEA-708 standard allocates 9,600 bps fixed bandwidth for subtitles, and within this range, totals six standard services (Service # 1 to Service # 6) and up to 57 extended services (Service # 7 to Service # 63). Provide 63 services.

The CEA-708 specification also stipulates that one service does not exceed 25% per second (2,400 bps on average) and recommends that the decoder be designed to handle the full 9600 bps band.

In Korea's TTAK.KO-07.0093 standard, the signaling of subtitle information through the subtitle service descriptor in the broadcasting environment based on MPEG-2 system should be done through PMT, and additionally by broadcasting media (ATSC, IPTV). , Cable) Subtitle information can be signaled according to Service Information standard.

The minimum requirement for the subtitle decoder and receiver is that the average per second of the total subtitle bandwidth does not exceed 25%, i.e. the decoder has the capability and buffer to handle subtitle data up to 2,400 bps per service.

2 is a diagram illustrating a digital broadcast bitstream structure, and FIG. 3 illustrates an example of a digital broadcast subtitle.

FIG. 4 shows an example of a DTVCC code set that expresses digital broadcasting subtitles as shown in FIG. 3.

Referring to FIG. 4, the DTVCC codeset assigns code values to code-space control, caption commands, and caption characters and symbols. The DTVCC codeset may be configured with four code groups: CL (C0, C2), GL (G0, G2), CR (C1, C3), and GR (G1, G3).

Here, EXT1 code (0x10) and P16 code (0x18) may exist in C0 of the CL code group. EXT1 code can be used as 2-byte extended code sequence by referring to C2, C3, G2, G3 codes of Extended Code, and P16 code can be used in countries using 16-bit characters such as Korea, China, and Japan. For example, in the TTAK.KO-07.0093 standard, the Korean subtitle data may use 'KS X ISO / IEC 10646' Unicode Korean code and 'KSX 1001: 2004' complete Korean code. In the case of the Korean subtitle service, each character in the form of P16 (0x18) + 2 bytes can be represented by 3 bytes.

5 is a diagram for explaining an example of a C1 codeset.

Referring to FIG. 5, caption command control codes (hereinafter referred to as caption commands) of standard codes used in the CEA-708 standard are shown. Here, the caption command may define creation and deletion of caption windows, properties and basic properties such as drawing, color, and position of caption characters.

As shown in FIG. 5, the subtitle expression command provided in the digital broadcasting environment defines only a subtitle command in a simple text format. To meet the eye level of non-disabled and hearing-impaired people who have already experienced spectacular open captions, expanded subtitle expression commands are needed.

Accordingly, the present invention proposes a method and apparatus for constructing a new CEA-708 subtitle command extended based on the CEA-708 standard for expressing various types of subtitles while maintaining compatibility with conventional subtitle standards. .

Hereinafter, the C2 codeset extension for commands not included in the C1 codeset of FIG. 5 will be described.

The C2 codeset may include at least one subtitle command of a KARAOKE function, an OUTLINE function, a SCALE function, a ROTATAION function, and a MOVE function.

-KARAOKE function (hereinafter karaoke function)

The karaoke function is a function that allows the subtitle string to change the color of a character or its background over time, as the color of a karaoke lyrics (character or its background) changes over time.

The coverage is applied to the text after On until the text is turned off.

Or, if another command is issued, turn it off.

Command Name: KARAOKE

Parameter: On / Off [1-bit]

Format: EXT1, ExtCode (KARAOKE), <On / Off [1]?>: 3-Byte

Code table: C2 code set 0x08 to 0x0F

-OUTLINE function

OUTLINE displays the color and size of the outline and the shadow of the outline. The outline width is 0 ~ 15 pixels, the outline color is the same as SPC gf_color, and Shadow means the shadow display.

Command Name: OUTLINE

Parameters: Outline On / Off [1-bit], Outline width [4-bit], Outline color [6-bit], Shadow on / off [1-bit]

Format: EXT1, ExtCode (OUTLINE), <On / Off [1] width [4] color [6] Shadow [1]?>: 4-Byte

Code table: C2 code set 0x10 to 0x17

-SCALE function

SCALE is a function that adjusts the flatness of the basic font of characters. It can apply either X or Y or both X and Y depending on the ratio of parameters. A value of 0 does not adjust.

Command Name: SCALE

Parameters: Font scale X [7-bit], Font scale Y [7-bit]

Format: EXT1, ExtCode (SCALE), <X [7-bit] Y [7-bit]?>: 4-Byte

Code table: C2 code set 0x10 to 0x17

-ROTATION function

ROTATION is a function that rotates the characters and then rotates the unit text according to the angles of the X, Y, and Z axes.

Command Name: ROTATION

Parameters: X axis angel [8-bit], Y axis angel [8-bit], Z axis angel [8-bit],

Format: EXT1, ExtCode (ROTATION), <X [8] Y [8] Z [8]>: 5-Byte

Code table: C2 code set 0x18 to 0x1F

-MOVE function

MOVE is a function that moves characters from X1 and Y1 to X2 and Y2. The X and Y positions are the same as the row and column of SPL in the C1 code set. The scope of application is the unit text after that.

Command Name: MOVE

Parameters: Position of X1 [6-bit], Position of Y1 [4-bit], Position of X2 [6-bit], Position of Y2 [4-bit]

Format: EXT1, ExtCode (MOVE), <X1 [6] Y1 [4] X2 [6] Y2 [4]?>: 5-Byte

Code table: C2 code set 0x18 to 0x1F

6 is a diagram illustrating a caption command of a C2 code set. In FIG. 6, the command name, extension code, command code, parameters, and caption command of the caption command of the C2 code set are described in detail.

7 is a flowchart illustrating a digital broadcast closed captioning service providing method according to an exemplary embodiment.

Referring to FIG. 7, the digital broadcasting closed caption data may be received (S701), and the caption may be displayed in a caption window based on the received digital broadcasting closed caption data (S702). Specifically, the digital broadcast closed caption data may be transmitted and received along with audio data, video data, and control data in the digital broadcast bitstream. When displaying audio data and video data, the caption can be displayed in the caption window based on the digital broadcast closed caption data.

Here, the digital broadcast closed caption data may include a code space control, a caption command, and a caption character, and the caption command may include at least one of a KARAOKE function, an OUTLINE function, a SCALE function, a ROTATION function, and a MOVE function.

Meanwhile, at least one subtitle command among the KARAOKE function, the OUTLINE function, the SCALE function, the ROTATION function, and the MOVE function may be included in an extended code set (C2 code set).

Here, the KARAOKE function may be a caption command having a function of changing the color of a character or a background with a character string of the caption.

Here, the OUTLINE function may be a caption command having a function of displaying the color, size and shadow of the outline of the caption outline.

Here, the SCALING function may be a caption command having a function of adjusting the longness of the character font of the caption.

Here, the ROTATION function may be a caption command of a function of rotating a character of the caption.

Here, the MOVE function is a caption command of a function of moving a caption character to a predetermined position.

Exemplary methods of the present disclosure are represented as a series of operations for clarity of description, but are not intended to limit the order in which the steps are performed, and each step may be performed simultaneously or in a different order as necessary. In order to implement the method according to the present disclosure, the illustrated step may further include other steps, may include other steps except some, or may include additional other steps except some.

The various embodiments of the present disclosure are not an exhaustive list of all possible combinations, and are intended to describe representative aspects of the present disclosure, and the matters described in the various embodiments may be applied independently or in combination of two or more.

In addition, various embodiments of the present disclosure may be implemented by hardware, firmware, software, or a combination thereof. For hardware implementations, one or more Application Specific Integrated Circuits (ASICs), Digital Signal Processors (DSPs), Digital Signal Processing Devices (DSPDs), Programmable Logic Devices (PLDs), Field Programmable Gate Arrays (FPGAs), General Purpose It may be implemented by a general processor, a controller, a microcontroller, a microprocessor, and the like.

It is intended that the scope of the disclosure include software or machine-executable instructions (eg, an operating system, an application, firmware, a program, etc.) to cause an operation in accordance with various embodiments of the method to be executed on an apparatus or a computer, and such software or Instructions, and the like, including non-transitory computer-readable media that are stored and executable on a device or computer.

Claims (1)

Receiving digital broadcast closed caption data; And
Displaying a caption in a caption window based on the digital broadcast closed caption data;
The digital broadcast closed caption data is composed of code space control, caption command and caption character,
And the caption command includes at least one of a KARAOKE function, an OUTLINE function, a SCALE function, a ROTATION function, and a MOVE function.

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