KR20120139514A - Method and apparatus for deliverying dash media file over mmt delivery system - Google Patents

Abstract

PURPOSE: A method for interlinking media data of DASH standards with an MMT(MPEG Media Transport) transmission system and a device thereof are provided to form complex media contents including the media data of DASH standards in a multimedia broadcasting system of MMT standards by substituting MMT standard data for the DASH standards. CONSTITUTION: An interlinking device analyzes media data of DASH standards. The interlinking device substitutes the media data for MMT transmission standards. The interlinking device generates a container and an identifier of the MMT transmission standards by using the substituted media.

Description

Method of interworking with DHS standard media data and MMT transmission system and apparatus therefor {METHOD AND APPARATUS FOR DELIVERYING DASH MEDIA FILE OVER MMT DELIVERY SYSTEM}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mobile communication system, and more particularly, to a method and an apparatus for interworking a DASH (Dynamic Adaptive Streaming over HTTP) standard with an MMT (MPEG Media Transport) transmission system.

Recently, the importance of the smooth transmission of contents has emerged due to the increase of users using online contents. As a result, adaptive streaming technology, in which a bit rate of a content is smoothly changed according to a change in available transmission bandwidth or a user's device performance, has been raised. This adaptive streaming technology optimizes the bit rate by analyzing the user's network environment. As such, the user terminal selects and plays a unit of content divided into small pieces based on the Hyper Text Transfer Protocol (HTTP) protocol such as adaptive streaming, so that the user can use the content without delay or interruption. The transmission technology to ensure this is being discussed in various standards bodies. One of the related standard is the DASH standard which is discussed in the MPEG standard. MPEG DASH is designed to achieve adaptive AV streaming by dynamically adapting to the network and terminal environments in the wired and wireless Internet in accordance with the current trend of AV streaming using HTTP / TCP instead of AV streaming using RTP / UDP, which is blocked by Internet firewalls. It is a standard for technology.

In the age of convergence based on IP, the convergence of communication and broadcasting is attracting attention as one of the next generation market leading technologies as a new marketable next generation new business model. In particular, IPTV (Internet Protocol Television), the largest axis of the Convergence of Broadcasting and Mobile Service (CBMS), provides not only a recombination or combination of existing TV, voice, and data technologies into one, but also supports two-way business. It is a technology that can create models and services. In particular, the IPTV technology is a fixed terminal such as set-top box, PC, TV and mobile terminals such as mobile phones, PDAs (Personal Digital Assistants) and the like, rather than providing specialized services in existing limited terminal environments, and terminals such as wired and wireless networks or broadcasting networks. By providing a service regardless of the network, the same service can be provided and applied in various environments, and various types of services can be found by considering various environments.

With the explosive growth of wired and wireless Internet, various forms of Internet TV will become a meaningful part of our future life. Right now, AV delivery over wired and wireless Internet cannot replace existing broadcasts, but it will develop into a hybrid service that combines broadcasting networks and the Internet. In addition, unlike the past, where a dedicated network was used to deliver content between studios or to a secondary distribution network, it is recently delivered through an IP network, thereby reducing the cost of a separate dedicated network and expensive equipment cost due to a specialized interface. The trend is to become stronger. In addition, the specification of the multimedia transmission system considering the plurality of network environments installed in the DTV and the mobile terminal is also discussed in the MPEG standard specification. To this end, the MPEG standard specification is divided into file standards for hybrid contents for hybrid services, transmission standards through hybrid networks, and control standards for providing broadcast and communication services.

The present invention provides a method and an apparatus for interworking a media data of the DASH standard with an MMT transmission system.

The present invention also provides a method and apparatus for constructing and generating composite media content including DASH standard media in an MMT standard multimedia broadcasting system.

In addition, the present invention provides a method and apparatus for generating in consideration of the characteristics of the various media constituting the composite media content including the DASH standard media in the multimedia broadcasting system of the MMT standard.

The present invention also provides a method and apparatus for transmitting MMT standard multimedia content in the DMT transmission standard in a multimedia broadcasting system of the MMT standard.

The interworking method of the media data of the DASH structure and the MMT transmission system according to the present invention comprises the steps of analyzing the media data of the DASH structure, replacing the media data with the MPEG MMT transmission format, and using the substituted media Generating a container and an identifier of the MPEG MMT structure. In addition, the interworking method between the media data of the DASH structure and the MMT transmission system includes analyzing and replacing the media data of the DASH structure with the MMT file structure, and transmitting the MMT using the substituted MMT file structure. .

1 is a diagram showing the structure of a media file defined in MPEG DASH;
2 is a diagram showing the structure of a composite media content and composite delivery system in MPG MMT;
3 is a view showing an interworking structure of a DASH and an MMT according to an embodiment of the present invention;
4 is a structural diagram of a DASH media file.

In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

First, prior to describing the present invention will be defined for the terms used in the present specification.

DASH: Dynamically variable HTTP-based streaming

-Content: creations such as movies, music, news, and storage forms

Content component: a component constituting content; (E.g. video, audio, subtitles)

-Representation: Representation of content can exist in low and high image quality.

The DASH encodes the same content component constituting the same content under different conditions (network bandwidth, resolution, codec, etc.). A group of adaptive combinations that represent information that satisfies various conditions representing language, representation attributes, and subtitles, by dividing the representations and the total content length into a plurality of periods. The attributes of this group can be composed only with the same media type or attributes, and can be combined or selected according to their conditions within the group. In addition, the content can be classified into a short enough time (eg 1 second to 10 seconds). Divide into segments (Segmentation) and specify the file name, sequence number, start time, length, etc. of each segment (Multimedia Presentation Description) MPD, which consists of (Manifest file roles).

And the segment comprises an initialization segment having information for decoder configuration and a segmented content components so as to properly decode the corresponding representation. (media segments).

The UE first requests and receives the MPD, checks which representations are provided, and then determines the performance of the client device, the capability, the network speed, and the like to select a suitable representation and fragment. In order to start playback.

If variables that can be changed, such as network bandwidth, change, i.e. at higher network speeds, the fragments of the higher-bandwidth representation are played back, resulting in image quality that depends on the speed of the network. Can have a lasting effect. In addition, by the selection of the user or the client terminal, the change of the available language and the combination of the media segments and the like can be selected and reproduced from the attribute information of the possible group of the aforementioned adaptive combination.

In order to receive the broadcast content service, the terminal receives MPD data describing the content from the server and requests a corresponding representation of the content based thereon.

In addition, the embodiment of the present invention will be described below using MPEG MMT technology, which is one of the technologies to which the present invention can be applied, but this description does not limit the content of the present invention.

Fig. 1 shows a structural diagram of a media file defined in MPEG DASH.

Referring to FIG. 1, the same content component constituting the same content in the structure diagram is encoded in different conditions (network bandwidth, resolution, codec, etc.) Divide the encoded representations and the total content length into a plurality of equal periods, and then repeat the period with a short enough time (for example, 1 second to 10 seconds) with information to satisfy various conditions. It is divided into segments (segmentation) and consists of a multimedia presentation description (MPD) (Manifest file role) that specifies the file name, sequence number, start time, and length of each segment.

4 shows the structure of the MPD defined in DASH.

Referring to FIG. 4, in the MPD file, Period, which is classified based on a duration, language-specific identifiers of subtitles and voice signals, media signal identifiers, role of representation, preference, and attributes used in common, examples For example, Adaptation Set, bitrate, and other conditions (networks, etc.) that are combined under the same conditions, such as width, height, diagonal length, number of frames, number of channels, signal sampling period, and media codec, can be combined. Representations encoded by bandwidth (network bandwidth, resolution, codec, etc.), and they are divided into time and space conditions according to playback conditions and transmission environment. Segment represented by) and size, and sub-segments separated for specific functions such as random play and double speed play. To this end, a plurality of periods, adaptation sets, representations, segments, and sub-segments may exist in a single MPD.

In addition, the operation of the DASH terminal receives the MPD from the server, analyzes the configuration of the period and the corresponding repetition step, requests data to the server using the HTTP protocol, and receives the representation data corresponding to the corresponding period. Decode and play by segment.

2 shows a structure diagram of a system for processing composite media content in MPEG MMT.

Referring to FIG. 2, each region is defined as described in Table 1 below in a system structure diagram for transmitting composite media content in a MPEG MMT in a composite network environment.

domain Justice Encapsulation functional area (E) defines the format for the encapsulation of encoded media data either to be stored on some storage device or to be carried as the payload of delivery protocols and networks Delivery functional area (D) provides formats and functionalities that are required for transferring encapsulated media data from one network entity to another Control functional area (C) provides functionalities to control delivery and consumption of the media

The above-mentioned encapsulation function area (E) performs media container format and media structuring, media segmentation information, media synchronization and media protection functions, and delivery function area (D) decodes transmission data considering transmission environment. In this regard, the data packetization and the size of the transmission data are adjusted to a size that can be transmitted in consideration of the transmission environment. The control function area (C) is responsible for service search and advertisement for initial service search, control of transmission environment and complex media in service. Also, in some cases, a function of transmitting and receiving control signals for random reproduction and double speed reproduction is performed.

Encapsulation consists of Media Fragment Unit, M-Unit, MMT Asset, and MMT Package.

The media fragment unit is a general storage format in which the media data included in the MFU can be used independently of a specific media codec, and is multi-layered according to codec type information, priority of encoded data, reference information of corresponding media data, and encoding type. Signal information, including the start, middle, and last identifier of the MFU configured in a group form, and includes a number identifier for identification of the group MFU.

The M-Unit may include a singular or plural number of AUs, which is a decoding unit, and may be prepared to include a singular or plural MFU. In this case, in order to express the M-Unit to be processed in the same time, the time information related to the reproduction, and the points for double speed reproduction and random reproduction are managed.

The asset is composed of a single or a plurality of M-Unit, there may be a single or various types of media. Asset has various metadata such as media data identifier information for identifying composite media content, data size information and identifier indicating whether setting information for setting media codec is included.

The MMT Package may include a plurality of MMT Assets, and additionally includes information CI indicating a space-time relationship and information TC considering a transmission environment.

The MMT Asset is a component of the MMT Package and may include audio, video, and program information. Examples of the MMT Asset include an MPEG-2 TS stream, a PES packet, an MP4 file format, an MPEG-U widget data, and a still image signal. Can be used as

3 shows an interworking structure between a DASH and an MMT according to an embodiment of the present invention.

Referring to FIG. 3, the MPD data portion of the DASH standard should be able to be re-standardized and transmitted as control information that can provide the MMT service and the media to the terminal. The adaptive structure that can be provided according to the type of media and the type of media must be provided to replace the structure of the MMT. In some cases, it can be provided using the identifier of media-type / dash which is a file standard of DASH.

More specifically, this is a process of converting DASH standard data into MMT Encapsulation data. To this end, the time information of the period present in the DASH MPD information and the adaptive group configuration information of the adaptation set are converted into information CI representing a space-time relationship of the MMT package and information TC considering a transmission environment. In addition, the various condition information representing the representation may include various meta-data such as media data identifier information for identifying the composite media content, data size information, and identifier indicating whether setting information for setting the media codec is included or not. Is converted to data. In addition, the size information of the DASH segment and the information indicating the address of the next segment may be converted into the stream ID information of the asset and the time configuration information of the M-Unit.

In addition, the information to be provided to the MMT D layer is described in the MPD byte range information of the data for transmitting the DASH media data is the size of the transmission data of the MMT, the bit rate of the media provided in the representation is It can be replaced by the average bit rate among the network transmission parameters. In addition, the information on the use of the HTTP protocol provided in the DASH specification can be used by converting the loss rate and the delay time of the transport characteristics provided by the MMT E layer. Configuration information of each segment of the DASH is provided in a manner similar to real-time broadcasting, which must be provided as continuous packet information using a sequence number for MMT transport packet configuration.

As for the interworking method of the MPEG DASH standard and the MPEG MMT standard mentioned above, it means that the MMT standard data can be replaced with the DASH standard.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments, but is capable of various modifications within the scope of the invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the appended claims, but also by the equivalents of the claims.

Claims (2)

In the interworking method of the media data of the DASH (Dynamic Adaptive Streaming over HTTP) standard and MPEG Media Transport (MMT) transmission system,
Analyzing the DASH-compliant media data,
Replacing the media data with an MMT transmission standard;
And generating a container and an identifier of the MMT transmission standard using the substituted media.
In the interworking method of the media data of the DASH (Dynamic Adaptive Streaming over HTTP) standard and MPEG Media Transport (MMT) transmission system,
Analyzing the media data of the DASH structure and substituting the MMT file structure;
Method of interworking with the DASH standard media data and the MMT transmission system comprising the step of transmitting the MMT using the substituted MMT file structure.

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