KR20230118451A - A method for receiving a broadcast signal and an apparatus for receiving a broadcast signal - Google Patents

Abstract

A method for receiving a broadcast signal according to embodiments includes receiving a broadcast signal by a receiving unit; extracting media data included in the broadcast signal; requesting a media server of a receiving unit to display media data; and reproducing the media data by the reproducing unit; can include A broadcast signal receiving apparatus according to embodiments includes a receiving unit for receiving a broadcast signal; and a reproduction unit extracting and reproducing media data included in the broadcast signal. Including, the playback unit may request media data from the media server of the receiving unit.

Description

Broadcast signal receiving method and broadcast signal receiving apparatus

The present invention relates to a broadcast signal receiving apparatus and a broadcast signal receiving method.

As analog broadcasting signal transmission ends, various technologies for transmitting and receiving digital broadcasting signals are being developed. A digital broadcasting signal may include a larger amount of video/audio data than an analog broadcasting signal, and may further include various types of additional data as well as video/audio data.

That is, the digital broadcasting system can provide high definition (HD) images, multi-channel audio, and various additional services. However, for digital broadcasting, data transmission efficiency for a large amount of data transmission, robustness of a transmission/reception network, and network flexibility in consideration of mobile reception devices must be improved.

In order to achieve the above object and other advantages, a broadcast signal reception method according to an embodiment of the present invention includes the steps of receiving media and metadata related to the media, storing the media in a server, and media based on the metadata. It may include the step of displaying.

The present invention can provide various broadcast services by processing data according to service characteristics and controlling Quality of Service (QoS) for each service or service component.

According to the present invention, it is possible to provide a method and apparatus for transmitting and receiving broadcast signals capable of receiving digital broadcast signals without errors.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included to provide a further understanding of the present invention and which are incorporated in and constitute a part of this application, show embodiments of the present invention together with detailed descriptions explaining the principles of the present invention.
1 shows a broadcast signal receiving apparatus according to embodiments.
Figure 2 shows a media segment according to embodiments.
3 shows the structure of a broadcast signal receiving apparatus according to embodiments.
4 shows a synchronization process according to embodiments.
5 shows a synchronization process according to embodiments.
6 shows a structure of a broadcast signal reception device according to embodiments.
7 shows a broadcast signal receiving method according to embodiments.

Preferred embodiments of the present invention will be described in detail, examples of which are shown in the accompanying drawings. The detailed description below with reference to the accompanying drawings is intended to describe preferred embodiments of the present invention rather than only showing embodiments that can be implemented according to the embodiments of the present invention. The following detailed description includes details for the purpose of providing a thorough understanding of the present invention. However, it is apparent to one skilled in the art that the present invention may be practiced without these details.

Most of the terms used in the present invention are selected from common ones widely used in the field, but some terms are arbitrarily selected by the applicant and their meanings are described in detail in the following description as needed. Therefore, the present invention should be understood based on the intended meaning of the term rather than the simple name or meaning of the term.

1 shows a broadcast signal receiving apparatus according to embodiments.

A broadcast signal reception device according to embodiments may include a receiver 100, a playback unit 110, a caption module 120, an application unit 130, and the like. Each component may correspond to hardware, software, processors, and/or combinations thereof.

A receiving device according to embodiments may be interpreted as a device including a receiving unit and/or a reproducing unit. Also, the receiving unit according to the embodiments may be referred to as a reproducing unit.

The receiving unit 100 may receive a broadcast signal. A broadcast signal according to embodiments may follow the ATSC 3.0 standard. A broadcast signal received by the receiver may include audio data, video data, time information (Wall Clock), and audio/video metadata. According to embodiments, audio data and/or video data may be referred to as media or media data.

For hybrid broadcasting, a broadcast receiving device can freely access a communication network (broadband). In addition, the broadcast reception device can reproduce content received through a communication network (broadband). To this end, a broadcast reception device and a broadcast transmission device support a content transmission protocol supporting both a broadcasting network and a communication network (broadband). To this end, MPEG-Dynamic Adaptive Streaming over HTTP (DASH), which is a standard technology for adaptive transmission of media contents by a broadcast transmission device and a broadcast reception device according to a network environment, and/or transmission for efficient transmission of media contents over an IP network. Standard MPEG Media Transport (MMT) can be used. According to embodiments, a receiving device may receive a broadcast signal based on various protocols. According to the MPEG-DASH standard, media contents can be transmitted and received through an IP network.

The receiver may parse a Media Presentation Description (MPD) and parse a segment including video/audio. In addition, the receiving device may include a media engine that transmits an HTTP request message and receives an HTTP response message, and plays an HTTP client and media.

The broadcast reception device may receive media content reproduction information through an IP transceiver. In a specific embodiment, media content presentation information may be MPD according to the MPEG-DASH standard.

Media content may be in MPEG-DASH format. Specifically, media content may be encapsulated in an ISO Base Media File Format (ISO BMFF) and transmitted through an MPEG-DASH protocol. A broadcast reception device may extract an MPEG-DASH segment from a ROUTE packet. Also, the broadcast receiving device may extract an ISO BMFF file from an MPEG-DASH segment.

The receiving device processes a packet including system time information that is a reference for media content reproduction. Also, the system clock may be controlled based on system time information.

The system clock provides a reference clock that is a reference for the operation of the broadcast reception device.

A receiving device according to embodiments processes MPEG-DASH segments. Specifically, the DASH client included in the receiving unit may process MPEG-DASH segments received through a communication network. Also, the DASH client may be included in the playback unit. In addition, in detail, the DASH client may process MPEG-DASH segments extracted from the application layer of a broadcast signal received through a broadcast network. Adaptive media streaming based on HTTP may be referred to as dynamic adaptive streaming over HTTP (DASH).

Figure 2 shows a media segment according to embodiments.

FIG. 2 shows a structure of a media segment processed by the apparatus for receiving broadcast signals of FIG. 1 .

A media segment according to embodiments may include audio data, video data, and subtitle data according to a time axis. That is, since audio/video/captions can be arranged according to time, audio/video/captions suitable for the current time can be provided.

Audio data, video data, and subtitle data included in a media segment may have time information. The time information may indicate a start time of each data.

For example, A100 means audio data that starts playing at 100 seconds. V100 means video data that starts playing at 100 seconds. S100 means caption data starting at 100 seconds.

The playback unit 110 may request a media segment from the receiver 100, receive the media segment from the receiver, and reproduce video/audio/subtitles in time.

For example, a difference between received media data and media data to be played may occur due to an error occurring in the process of receiving a broadcast signal. The media segment 210 is a media segment requested by the playback unit to the receiver. The media segment 200 is a media segment actually received by the receiver. The playback unit should reproduce video/audio/subtitles at 200 seconds, but the receiver may not receive the video/audio/subtitles that fit 200 seconds, or an error may occur in transmitting the received data. Since the receiving device has only video/audio/caption data corresponding to 100 seconds, a media synchronization problem may occur after this time.

Occurrence of errors according to embodiments may include a case in which data is missing in the process of receiving data and/or an error occurring in data packaging in the process of transmitting data. For example, when packaging data, there may be cases where media and time related to the media are not synchronized with each other. There may be mismatch between wall clock information, media related time information, and media.

For example, at a specific time point 220, the receiving device may perform channel switching. The player may request a media segment corresponding to 200 seconds from the receiver based on the time information (Wall Clock). However, the receiving unit may have only media segments corresponding to 100 seconds without media data corresponding to 200 seconds. The playback unit may receive a video corresponding to 100 seconds from the receiving unit, display the video, and transmit information of 200 seconds, which is the current time, to the application and/or the subtitle module. The receiving device may generate an error between the video currently being rendered and the current time. That is, since the caption module receives and uses current time information that is not synchronized with the video being rendered, an error occurs in caption synchronization. Furthermore, since the application unit receives and uses the current time information that has an error with the video being rendered, the application unit cannot provide the intended operation to the user at a desired time point.

For example, the playback unit calculates segment number information ($Number$) ($Number$ of SegmentTemplate element) based on the wallclock (UTC) of the received ATSC3.0 signal and requests it to the receiver. However, many streams have a problem that the TOI (Transport Object Identifier) field of the ROUTE packet received through the ATSC3.0 signal does not match $Number$. If playback starts without solving this problem, the playback unit has time-related information corresponding to a segment corresponding to 200 seconds, but the actual content is rendered with a segment corresponding to 100 seconds (eg, video), so the playback unit, like subtitle rendering, A sync error occurs when the time information transmitted from is to be used.

By substituting the TOI field number value of the ROUTE packet received by the receiver through the ATSC3.0 signal into $Number$ of the playback unit, the playback unit can request the actually received ROUTE packet. Through this, the time-related information of the playback unit is generated based on the actually received ROUTE packet, and operation errors of other modules using it are prevented.

3 shows the structure of a broadcast signal receiving apparatus according to embodiments.

FIG. 3 shows a structure of a playback unit 110 and a media server connected to the playback unit of the apparatus for receiving broadcast signals of FIG. 1 . The reproducing unit 300 corresponds to the reproducing unit 110 of FIG. 1 .

The media server 310 may perform a request/response process for media reception with a playback unit. The media server may be a local cache server.

The playback unit may transmit an HTTP request to the media server. The playback unit may receive an HTTP response from the media server.

A method and apparatus for receiving a broadcast signal according to embodiments include a process in which a playback unit requests and receives a first media segment from a media server. The player may download the media segments from the server. The playback unit needs to synchronize the associated media segments. For example, when there is a channel change, the DASH-based playback unit calculates a location where media is to be reproduced and requests a media segment corresponding to the location from the media server. The media server transmits the media segment requested by the playback unit to the playback unit. In order to accurately handle requests and transmissions for media segments, an identifier for identifying a segment according to embodiments may be provided. In order to specify the identifier, in the case of the DASH protocol, number information ($Number$) and/or time information ($Time$) may be used. For ATSC 3.0, the $TOI$ field is available.

If the media server does not have the segment requested by the playback unit, the media server may transmit an HTTP response message. The HTTP response message may include an available file name header field. A segment currently in the media server is transmitted to the playback unit through available file name information, and the playback unit may synchronize the timeline according to the received segment. This operation may be referred to as TOI synchronization according to embodiments.

A ROUTE receiver according to embodiments may perform the following operations to correctly identify a DASH segment.

If $Number$ based addressing is used, the TOI field of a given ROUTE packet can be set to the $Number$ value of the DASH segment. The ROUTE file mode with EFDT can be used. TOI values of 0 and 1 may not be generated.

When using $Time$ based addressing, without segment sequences, the length of the $Time$ value may not exceed 32 bits. The TOI field of a given ROUTE packet may be set to the $Time$ value of the DASH segment. $Time$ values of 0 and 1 may not be used.

If $Time$-based addressing is used and the length of the $Time$ value exceeds 32 bits, the ROUTE entity mode can be used.

When segment sequences are used with hierarchical addressing, entity mode ROUTE may be applied to properly signal segments.

For example, number-based segment templates mean that the $NUMBER$ field is used to express template-based segment URLs in the DASH specification. A time-based segment template means using the $TIME$ identifier when expressing a template-based segment URL in the DASH specification.

In the method and apparatus for receiving a broadcast signal according to the embodiments, when a channel is changed, the playback unit reproduces the first media segment received from the local server. An error may occur if the playback unit does not receive a media segment for a certain period of time after switching channels.

4 shows a synchronization process according to embodiments.

FIG. 4 illustrates a process in which the apparatus for receiving broadcast signals according to the embodiments shown in FIGS. 1 and 3 performs media synchronization. The playback unit 400 corresponds to the playback unit 110 of FIG. 1 and the playback unit 300 of FIG. The media server 410 corresponds to the media server 310 of FIG. 3 . According to embodiments, a media server may be referred to as a server for short.

The playback unit may transmit request information 420 to the media server. Request information according to embodiments may be HTTP Request. The request information may include information about a media segment requested by the playback unit. Request information may include GET + [media identification information]. For example, segment 3020209913 audio data or segment 3020209913 video data may be included in the request information.

The playback unit may receive response information 430 from the media server. Response information according to embodiments may be HTTP Response. For example, when changing a channel, the playback unit requested a media segment, but the media server may not have the media segment 420 requested by the playback unit. The media server may transmit response information including information indicating that there is no requested segment to the playback unit. Furthermore, the media server may transmit response information 430 including information about the media segment possessed by the media server in order to solve the problem that the playback unit provides out-of-synchronization media services. For example, the response information 430 may include information indicating available files. The available file names field indicates that segment 3020209913 requested by the playback unit does not exist, but segment 3043272953 exists on the current server.

The playback unit may transmit request information 440 to the media server. Request information 440 according to embodiments may be HTTP Request. The request information 440 may include information requesting the segment 3043272953 currently possessed by the media server.

The playback unit may receive response information 450 from the media server. Response information according to embodiments may be HTTP Response. The response information may include information indicating that there is a segment requested by the playback unit.

5 shows a synchronization process according to embodiments.

FIG. 5 illustrates a process in which the apparatus for receiving broadcast signals according to the embodiments shown in FIGS. 1 and 3-4 performs media synchronization from the perspective of a playback unit.

The playback unit S500 may request and receive segments having $NUMBER$ and/or $TIME$ from the server. When changing a channel, the playback unit may request a segment from the server.

S501 If the segment requested by the playback unit exists in the server, for example, if segment 200 (see FIG. 2) exists in the server, the playback unit plays the segment obtained from the server according to the current time, and the subtitle module and/or application unit plays the segment according to the current time. It is possible to provide additional services synchronized with

S502 The playback unit requests a segment from the server, and when the waiting time expires, the segment request process may be terminated. The playback unit may detect a segment acquisition error.

S503 The playback unit requests a segment from the server, and if the server does not have the requested segment, it may perform segment reception and synchronization. In particular, the playback unit may receive a segment (different from the segment requested by the playback unit) stored in the server due to channel switching. At this time, segment reception and synchronization may be performed in the same manner as in FIG. 4 . For example, when the playback unit requests segment 200 through channel switching, but the server does not have segment 200 but has segment 100, information on segment 100 is transmitted to playback unit, and playback unit receives segment 100. , the current time can be synchronized according to segment 100.

S504 The playback unit may detect a media transmission/reception error through segment information. For example, the playback unit may confirm that the value of the $NUMBER$ field or the $TIME$ field related to the media segment gradually increases as the segment is received. If there is a missing segment during media transmission, a specific value of the $NUMBER$ field or $TIME$ field may be temporarily missing. The playback unit may detect a temporary transmission error and retry to acquire the media segment from the receiver and the server. If the segment is normally received, the current time can be synchronized according to the segment time. In addition, when the value of the field is abnormally decreased, retries may be attempted as many times as the number of times corresponding to the set value. For example, 2 retries may be set according to embodiments. Specifically, if a segment is missing in the media transmission process, a specific value of the number field and/or time field is missing. In addition, while it is common for the value of the number field and/or time field to linearly increase during the media transmission process, when the system is restarted in the sending server, etc., a new number field and/or time field are assigned to a specific value of the field. A decrease may also occur.

A segment synchronization process according to embodiments of S503 is as follows.

1. A number or time value is extracted from an available file name using media format information described in the MPD. For example, the available file name field could refer to segment 3043272953.

2. Calculate the time based on the number extracted using the media format information described in the MPD.

3. Set the time to the current time of the playback unit.

4. Reconstruct the segment's url to request based on the updated current time.

6 shows a structure of a broadcast signal reception device according to embodiments.

FIG. 6 shows the structure of the apparatus for receiving broadcast signals shown in FIGS. 1 and 3-5. Each component may correspond to hardware, software, processors, and/or combinations thereof.

A broadcast signal receiving apparatus according to embodiments may include a receiving unit and a reproducing unit.

The receiving unit may control a process of receiving and parsing a broadcast signal through a broadcaster handler. The receiving unit may receive and control broadcast signals through a pipeline.

The tuner may receive a broadcast signal based on RF, and the demodulator may demotulate the broadcast signal based on the OFDM scheme.

The receiver may include a media server, and the media server may provide data about media content included in a broadcast signal.

The reproducing unit may display the broadcast signal received by the receiving unit. If there is an application related to the media content, the playback unit may perform synchronization between the media and the application. The playback unit may parse, decode, and render the media content through the demultiplexer.

A broadcast signal reception device according to embodiments may include a physical module, middleware, media server, player, and/or renderer. The receiving device may process the broadcast signal in the physical layer through the physical module and deliver it to middleware. Middleware can extract application program data included in broadcast signals. The middleware may process EPG (Electronic Program Guide) information, content schedule information, and the like. A media server may provide various media contents. The player corresponds to a playback unit that reproduces media content. The renderer may render media data including video/audio/subtitles/application data and the like.

7 shows a broadcast signal reception method according to embodiments.

Figure 7 shows how the device shown in Figure 6 performs.

S700, a broadcast signal receiving method according to embodiments may include receiving a broadcast signal. A broadcast signal can be received by the receiving unit 100 in FIG. 1 or the like.

S710, the broadcast signal receiving method according to the embodiments may further include extracting media data included in the broadcast signal. Media data included in a broadcast signal can be extracted from a physical layer according to the ATSC standard. An extraction process according to embodiments is referred to as a decapsulating process and may be performed by a decapsulator.

S720, the broadcast signal receiving method according to the embodiments may further include requesting to display media data. The playback unit that reproduces the media data may request media data to be played at the current time from the receiver that has received the broadcast signal. In relation to the request and synchronization operation according to the embodiments, the process of FIGS. 4 to 5 may be included.

S730, the broadcast signal receiving method according to the embodiments may further include reproducing the acquired media data.

Referring to Figure 1, an apparatus according to embodiments includes a receiving unit for receiving a broadcast signal; and a reproduction unit extracting and reproducing media data included in the broadcast signal. The playback unit may request the media data from the media server of the receiving unit.

Referring to FIG. 2 , regarding media content according to time, a broadcast signal includes signaling information about media data, and the media data may include video data, audio data, and subtitle data based on time information.

Referring to FIG. 3 , in relation to the request/response process, the player may request media data from the media server, and the media server may transmit a response to the request of media data from the player.

Referring to FIG. 4, in relation to a media request and an available file name, when the playback unit transmits request information including information about media data to a media server, and the media server includes media data corresponding to the request information, Response information including information about media data is transmitted to the playback unit, and when the media server does not include media data corresponding to the requested information, response information including information about currently available media data is sent to the playback unit. can transmit

Referring to FIG. 5, in relation to synchronization of time information, when the media server does not include media data corresponding to the requested information, the playback unit receives response information including information about currently available media data, and Time information for media playback of the playback unit may be set by extracting at least one of time and number information from media data information.

Referring to FIG. 5, in relation to error detection based on a time field or a number field, when time information included in signaling information included in a broadcast signal is smaller than time information on media data requested by the playback unit, the playback unit detects an error. and, when the number information included in the signaling information included in the broadcast signal is smaller than the number information on the media data requested by the playback unit, the playback unit may detect an error.

Through this, it is possible to accurately synchronize between the media actually received and the media actually played, and when the media to be played is not received or there is an error, the receiving device efficiently detects a reception error, and appropriate appropriate media based on the media currently received. There is an effect of providing media services.

Embodiments have been described in terms of methods and/or devices, and descriptions of methods and devices may be applied interchangeably.

For convenience of description, each drawing has been divided and described, but it is also possible to design to implement a new embodiment by merging the embodiments described in each drawing. And, according to the needs of those skilled in the art, designing a computer-readable recording medium in which programs for executing the previously described embodiments are recorded falls within the scope of the embodiments. As described above, the device and method according to the embodiments are not limited to the configuration and method of the embodiments described above, but the embodiments are selectively combined with all or part of each embodiment so that various modifications can be made. may be configured. Although preferred embodiments of the embodiments have been shown and described, the embodiments are not limited to the specific embodiments described above, and common knowledge in the art to which the present invention pertains without departing from the gist of the embodiments claimed in the claims. Of course, various modifications are possible by those who have, and these modifications should not be individually understood from the technical spirit or prospects of the embodiments.

Various components of the device of the embodiments may be implemented by hardware, software, firmware or a combination thereof. Various components of the embodiments may be implemented as one chip, for example, as one hardware circuit. According to embodiments, components according to the embodiments may be implemented as separate chips. Depending on the embodiments, at least one or more of the components of the device according to the embodiments may be composed of one or more processors capable of executing one or more programs, and the one or more programs may be executed. Any one or more of the operations/methods according to the examples may be performed or may include instructions for performing the operations/methods. Executable instructions for performing methods/operations of an apparatus according to embodiments may be stored in a non-transitory CRM or other computer program products configured for execution by one or more processors, or may be stored in one or more may be stored in transitory CRM or other computer program products configured for execution by processors. In addition, the memory according to the embodiments may be used as a concept including not only volatile memory (eg, RAM) but also non-volatile memory, flash memory, PROM, and the like. Also, those implemented in the form of a carrier wave such as transmission through the Internet may be included. In addition, the processor-readable recording medium is distributed in computer systems connected through a network, so that the processor-readable code can be stored and executed in a distributed manner.

In this document, “/” and “,” shall be interpreted as “and/or”. For example, “A/B” is interpreted as “A and/or B” and “A, B” is interpreted as “A and/or B”. Additionally, "A/B/C" means "at least one of A, B and/or C". Also, “A, B, C” means “at least one of A, B and/or C”. Additionally, “or” shall be construed as “and/or” in this document. For example, “A or B” may mean 1) only “A”, 2) only “B”, or 3) “A and B”. In other words, “or” in this document may mean “additionally or alternatively”.

Terms such as first, second, etc. may be used to describe various components of the embodiments. However, interpretation of various components according to embodiments should not be limited by the above terms. These terms are used to distinguish one component from another. only thing only thing For example, a first user input signal may be referred to as a second user input signal. Similarly, the second user input signal may be referred to as the first user input signal. Use of these terms should be construed as not departing from the scope of the various embodiments. Although both the first user input signal and the second user input signal are user input signals, they do not mean the same user input signals unless the context clearly indicates otherwise.

Terms used to describe the embodiments are used for the purpose of describing specific embodiments and are not intended to limit the embodiments. As used in the description of the embodiments and in the claims, the singular is intended to include the plural unless the context clearly dictates otherwise. and/or expressions are used in a sense that includes all possible combinations between the terms. The expression includes describes that there are features, numbers, steps, elements, and/or components, and does not imply that additional features, numbers, steps, elements, and/or components are not included. . Conditional expressions such as when ~, when, etc., used to describe the embodiments, are not limited to optional cases. When a specific condition is satisfied, a related action is performed in response to the specific condition, or a related definition is intended to be interpreted.

Also, operations according to embodiments described in this document may be performed by a transceiver including a memory and/or a processor according to embodiments. The memory may store programs for processing/controlling operations according to embodiments, and the processor may control various operations described in this document. A processor may be referred to as a controller or the like. Operations in embodiments may be performed by firmware, software, and/or a combination thereof, and the firmware, software, and/or combination thereof may be stored in a processor or stored in a memory.

Meanwhile, operations according to the above-described embodiments may be performed by a transmitter and/or a receiver according to embodiments. The transmitting/receiving device may include a transmitting/receiving unit for transmitting/receiving media data, a memory for storing instructions (program codes, algorithms, flowcharts and/or data) for processes according to embodiments, and a processor for controlling operations of the transmitting/receiving device. can

A processor may be referred to as a controller or the like, and may correspond to, for example, hardware, software, and/or combinations thereof. Operations according to the above-described embodiments may be performed by a processor. Also, the processor may be implemented as an encoder/decoder for the operations of the above-described embodiments.

Claims (12)

receiving a broadcast signal by a receiver;
extracting media data included in the broadcast signal;
requesting a media server of the receiving unit to display the media data; and
reproducing the media data by a playback unit; including,
How to receive a broadcast signal.
According to claim 1,
The broadcast signal includes signaling information about the media data,
The media data includes video data, audio data, and subtitle data based on time information.
How to receive a broadcast signal.
According to claim 1,
The playback unit requests the media data from the media server;
The media server transmits a response to the request for the media data to the playback unit.
How to receive a broadcast signal.
According to claim 3,
The playback unit transmits request information including information about the media data to the media server;
When the media server includes the media data corresponding to the request information, transmits response information including information about the media data to the playback unit;
When the media server does not include the media data corresponding to the request information, transmitting response information including information about currently available media data to the player,
How to receive a broadcast signal.
According to claim 4,
If the media server does not include the media data corresponding to the request information,
The playback unit receives response information including information on the currently available media data, extracts at least one information of time or number from the information on the currently available media data, and performs media playback of the playback unit. to set time information,
How to receive a broadcast signal.
According to claim 3,
The playback unit detects an error of the playback unit when the time information included in the signaling information included in the broadcast signal is smaller than the time information on the media data requested by the playback unit;
The playback unit detects an error of the playback unit when the number information included in the signaling information included in the broadcast signal is smaller than the number information on the media data requested by the playback unit.
How to receive a broadcast signal.
a receiver for receiving a broadcast signal; and
a reproduction unit extracting and reproducing media data included in the broadcast signal; including,
The playback unit requests the media data from the media server of the receiving unit.
Broadcast signal receiving device.
According to claim 7,
The broadcast signal includes signaling information about the media data,
The media data includes video data, audio data, and subtitle data based on time information.
Broadcast signal receiving device.
According to claim 7,
The playback unit requests the media data from the media server;
The media server transmits a response to the request for the media data to the playback unit.
Broadcast signal receiving device.
According to claim 9,
The playback unit transmits request information including information about the media data to the media server;
When the media server includes the media data corresponding to the request information, transmits response information including information about the media data to the playback unit;
When the media server does not include the media data corresponding to the request information, transmitting response information including information about currently available media data to the player,
Broadcast signal receiving device.
According to claim 10,
If the media server does not include the media data corresponding to the request information,
The playback unit receives response information including information on the currently available media data, extracts at least one of time or number information from the information on the currently available media data, and performs media playback of the playback unit. to set time information,
Broadcast signal receiving device.
According to claim 9,
The playback unit detects an error of the playback unit when the time information included in the signaling information included in the broadcast signal is smaller than the time information on the media data requested by the playback unit;
The playback unit detects an error of the playback unit when the number information included in the signaling information included in the broadcast signal is smaller than the number information on the media data requested by the playback unit.
Broadcast signal receiving device.