KR20170081608A - Apparatus and method for providing streaming contents - Google Patents

Abstract

A method and apparatus for an adaptive HTTP streaming service using metadata for content is disclosed. The metadata includes one or more base URL elements. The URL of the segment comprising the media is generated based on one or more base URL elements. The URL of the segment may generate the URLs of the segment by mapping any of the base URL elements of one or more base URL elements to the source URL attribute of the segment. The generated URLs all point to the same segment.

Description

[0001] APPARATUS AND METHOD FOR PROVIDING STREAMING CONTENTS [0002]

TECHNICAL FIELD The present invention relates to a streaming content providing technology, and more particularly, to an apparatus and method for providing media content using adaptive streaming.

Streaming is one of the methods for transmitting and reproducing multimedia contents such as sound and video. The client can play the above content while receiving the content through streaming.

The adaptive streaming service means providing a streaming service through a communication method composed of a client's request and a server's response to the request.

A client may request a media sequence suitable for its environment (e.g., its own transport channel) through an adaptive streaming service, and the server may request a media sequence corresponding to the client's request among various quality media sequences of its own .

Adaptive streaming services can be provided based on various protocols.

The HTTP adaptive streaming service means an adaptive streaming service provided based on the HTTP protocol. The client of the HTTP adaptive streaming service can receive the content from the server using the HTTP protocol and can transmit the request related to the streaming service to the server.

One embodiment of the present invention may provide an apparatus and method for interpreting a URL of a segment using one or more base URL elements in playing back the content.

One embodiment of the present invention may provide an apparatus and method for generating a URL of a segment by mapping any of the one or more base URL elements to a source URL attribute of the segment.

According to one aspect of the present invention, there is provided a method comprising: receiving metadata of a media, the metadata including one or more base Uniform Resource Locator (URL) elements; Wherein the URL is interpreted relative to the base URL element, receiving the segment, and decoding and rendering data of the media contained within the segment. / RTI >

The request may be an HTTP GET method.

The metadata may include a range attribute.

The request may be a request for bytes specified by the scope attribute of the resource indicated by the URL.

The URL may be an absolute URL or a relative URL.

Multiple locations pointed to by the URLs correlated and interpreted by each of the one or more base URL elements may access the same segments.

The first base URL of the one or more base URL elements may be used as a basic Universal Resource Indicator (URI), and the remaining base URL elements, excluding the first base URL element, May be a base URL.

The metadata may optionally include a source URL attribute of the segment, and when the metadata selectively includes the source URL attribute of the segment, any one of the one or more base URL elements The URL can be generated by mapping a URL element to the source URL attribute.

The metadata may be a media presentation description (MPD) of the media content.

The media may comprise a series of one or more periods.

The base URL element may comprise one or more media information level base URL elements for the media information and one or more period level base URL elements for the period.

The URL of the segment included in each cycle may be interpreted in correlation with the period level base URL element of the period.

The period level base URL element may be interpreted in correlation with the media information level base URL element.

Each of the one or more periods may comprise one or more groups.

The base URL element may further comprise one or more group level base URL elements for the group.

The URL of the segment included in each group may be interpreted in relation to the group level base URL element of the group

The group level base URL element may be interpreted in correlation with the period level base URL element.

Each of the one or more groups may include one or more representations.

The representation may be a structured collection of one or more components of the media in one of the periods.

The base URL element may further include one or more representation level base URL elements for the representation.

The URL of the segment included in each representation may be interpreted in relation to the representation level base URL element of the representation.

The representation level base URL element may be interpreted in relation to the group level base URL element or the period level base URL element.

According to another aspect of the present invention there is provided a method for receiving media metadata, the method comprising: receiving metadata of the media, the metadata including one or more base Uniform Resource Locator (URL) elements; An access engine that receives the segment and decodes the data of the media contained in the segments, and a processor that receives data of the media from the access engine And a media engine for receiving the media and outputting the media.

One embodiment of the present invention may interpret the URL of a segment using one or more base URL elements in playing the content.

One embodiment of the invention may generate the URL of the segment by mapping any of the one or more base URL elements to the source URL attribute of the segment.

Figure 1 illustrates categories of signaling information according to an example of the present invention.
FIG. 2 illustrates categories of signaling information according to an example of the present invention.
FIG. 3 illustrates the layers of a content division and levels of signaling information according to an example of the present invention.
Figure 4 illustrates the detection of virtual boundaries within an MPEG-2 TS according to an example of the present invention.
5 is a structural diagram of a terminal 100 according to an embodiment of the present invention.
6 is a structural diagram of a terminal 100 according to an embodiment of the present invention.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to or limited by the embodiments. Like reference symbols in the drawings denote like elements.

Dynamic Adaptive Streaming over HTTP (DASH) enables the delivery of media content from an HTTP server to an HTTP client, and 2) the content of content by standard HTTP caches. Specifies the formats that enable caching.

A media component may be any audio, video, or timed text having certain attributes, such as, for example, bandwidth, language or resolution. Is an encoded version of an individual media type.

Media content is a collection of media components that have a common timeline, such as video, audio, and subtitles. In addition, the media components may include relationships (e.g., individually, jointly, or mutually exclusive) as to whether the media components will be presented as a program or movie .

The media content and the content may be used in the same sense.

A media presentation is a structured collection of data that establishes bounded unbounded presentation of media content composed of components of contiguous media. is a collection.

That is, the media presentation is a structured collection of data accessible to the DASH client to provide the streaming service to the user.

A media presentation description (MPD) may be a formalized description of a media presentation.

The media presentation may be described by the MPD, including possible updates of the MPD.

The content may be content on demand or live content.

The content may be divided into one or more intervals. That is, the content may include one or more intervals.

Interval and period can be used in the same sense. The period may be a term of 3GPP (Generation Partnership Project) adaptive HTTP streaming.

The period may be the interval of the media presentation. A sequence of all the cycles constitutes a media presentation.

That is, the media presentation may comprise a series of one or more periods.

The one or more intervals may be a base unit. The one or more intervals may be described by signaling the metadata. That is, the metadata may describe each of one or more intervals.

The above metadata may be MPD.

The MPD may define a format for announcing resource identifiers for the segment. The MPD can provide a context for the identified resources within the media presentation. The resource identifiers may be HTTP-URLs. URLs may be limited by byte range attributes.

Each interval can be divided into fragments.

Fragments and segments may be used interchangeably. The segment may be a term of 3GPP (Generation Partnership Project) adaptive HTTP streaming.

The segment may be an object of a response to an HTTP / 1.1 GET request (or a GET request for a portion indicated by the byte range) to an HTTP-URL as defined in RFC 2616, entity body. < / RTI >

A terminal can play media content using received bytes (i.e., segments).

A sub-segment may mean a smallest unit in segments that can be indexed by a segment index at the segment level.

There can be a set of two or more fragments corresponding to one interval. Each of the sets of fragments is named as an alternative.

Alternatives and representations (or expressions) may be used interchangeably.

Each cycle may include one or more groups.

Each group may contain one or more representations of the same media content.

A representation is a structured collection of one or more media components in a cycle. The representation may be an alternate (e.g., multiple) representation of a subset of the media content or media content that has different encoding preferences, such as bitrate, resolution, language and codec, alternative, or choices.

The MPD (or MPD element) provides descriptive information that enables the client to select one or more presentations.

A random access point (RAP) is a specific location within a media segment. The RAP is identified as being the location where it can only continue to play back from the location of the RAP using only the information contained within the media segment.

Each representation may consist of one or more segments. That is, the representation may include one or more segments.

MPD is a document that contains metadata required by a DASH client to 1) access segments and 2) configure the appropriate HTTP-URLs to provide a streaming service to a user. HTTP-URLs can be absolute or relative.

MPD can be an XML-document.

The MPD may include an MPD element. The MPD may contain only one MPD element.

1 is a signal flow diagram of a content processing method according to an embodiment of the present invention.

The terminal 100 may be a DASH client.

DASH clients are compatible with the clients specified in RFC 2616.

A DASH client can use the HTTP GET method or HTTP partial GET method, as specified in RFC 2616, to contact segments or portions of segments.

Server 110 may host DASH segments. The server 110 may be compatible with the server specified in RFC 2616.

In step 120, the terminal 100 receives the metadata of the media (or the content) from the server 110. That is, the server 110 transmits the metadata about the media to the terminal 100.

The metadata may include a base Uniform Resource Locator (URL) element. The base URL element may be one or more.

In step 130, the terminal 100 processes the received metadata. In step 130, the terminal 100 may extract information provided by the metadata or information included in the metadata.

In steps 140 to 150, the terminal 100 accesses a segment of the media based on the information provided by the metadata.

Here, each period may include one or more groups, each group may include one or more representations of media, and each presentation may include one or more segments.

Metadata can describe a group element that describes a group.

In step 140, the terminal 100 requests the server 110 to segment the media using the URL of the segment. Here, the URL can be interpreted in correlation with the aforementioned base URL element. For example, the URL of the segment may be generated based on the base URL element.

The terminal 100 may request the server 110 for a suitable segment for a specific period based on the meta data processing. That is, the requested segment is selected based on the metadata. The request may be an HTTP GET method.

The metadata may include a range attribute. The request may be a request for bytes specified by the scope attribute of the resource pointed to by the URL.

The URL of the segment may be an absolute URL or a relative URL.

Multiple locations pointed to by URLs correlated and interpreted by each of one or more base URL elements approach the same segments. That is, the same segments can be selectively accessed by URLs provided by one or more base URL elements.

Also, the first base URL of one or more base URL elements may be used as a basic Universal Resource Indicator (URI), and the remaining base URL elements, except for the first base URL element of one or more base URL elements, may be an alternative base URL.

In addition, the metadata may optionally include a source URL attribute of the segment. If the metadata optionally includes the source URL attribute of the segment, any of the one or more base URL elements may be mapped to the source URL attribute to generate the URL of the segment.

In step 145, in some cases, the server 110 needs to parse the media (e.g., an MP4 file for the SVC) and extract the appropriate data part for the requested segment.

In step 150, the server 110 transmits appropriate segments to the terminal 100 for each request from the terminal 100. [ The terminal 100 receives segments from the server.

In step 160, the terminal 100 reproduces the media by decoding and rendering the data of the media contained in the segment.

The terminal 100 may play the media using the received segment by repeating steps 120-160.

At this time, the base URL element may include a media information level base URL element for media information, and may include a period level base URL element for each period. The cycle level base URL element is a base URL element that applies to the cycle it belongs to. That is, the URL of the segment included in each cycle is interpreted in correlation with the periodic level base URL element of the stock price.

The media information level base URL element may be one or more, and the period level base URL element may be one or more.

The base URL element may further include a group level base URL element for the group. The URLs of the segments included in each group can be interpreted relative to the group level base URL element of the group. The group level base URL element may be one or more.

The base URL element may further include a representation level base URL element for the presentation. The URL of the segment included in each representation may be interpreted relative to the representation level base URL element of the representation.

A base URL element at a particular level can be interpreted relative to its base URL element at the top level. For example, the period level base URL element may be interpreted relative to the media information level base URL element. The group level base URL element may be interpreted relative to the period level base URL element. The representation level base URL element can be interpreted relative to the group level base URL element or the period level base URL element.

FIG. 2 illustrates categories of signaling information according to an example of the present invention.

The signaling information (i.e., metadata) is divided into the following categories 1) to 4).

1) General information 210: General information includes a general description of the content and a general description of each interval, such as, for example, duration and start time.

2) Quality of Service (QoS) information 220: Describes characteristics of each alternative, such as bitrate, resolution, and quality. That is, the quality information of the service describes the characteristics of each of the alternatives of the content.

  The alternative can be physical (i.e., pre-generated) and virtual (i.e., to be generated on-the-fly). Based on the information of the alternatives, the client selects a suitable alternative fragment. Thus, it supports adaptability to the contexts of terminals and networks.

3) Mapping Information 230: Describes locations to retrieve contents. Depending on the particular cases, the different alternatives may have the same or different positions.

4) Client request 240: This kind of signaling information conforms to the format of the HTTP 1.1 request message. As shown in FIG. 1, the parameters requested by the client derive from the information of the above categories 1) to 3).

FIG. 3 illustrates the layers of a content division and levels of signaling information according to an example of the present invention.

The signaling of the metadata according to the temporal examples of the present invention may be physically separated into content-level information 310, interval level information 320, QoS information 330 and mapping 340 information. Linking of the content-level information 310, the interval level information 320, the QoS information 330 and the relevant portions of the mapping 340 is done by referencing.

These portions of the signaling information may be combined into different ways to support flexibility.

For example, when only content-level information 310 and interval level information 320 are sent to the client, calculations for all alternatives and resolutions of locations are performed by the server. Thus, the processing model when only content-level information 310 and interval level information 320 are transmitted to the client is "server-based ".

If the content-level information 310, the interval-level information 320 and the QoS information 330 are transmitted to the client, the calculations for all of the alternatives and resolutions of the locations are distributed by the client and the server . Thus, when the content-level information 310, the interval-level information 320 and the QoS information 330 are transmitted to the client, the model will be "distributed ".

When all of the signaling information (content-level information 310, interval-level information 320, QoS information 330 and mapping information 340) is sent to the client, most (or all) Because processing (i. E., Determination of alternatives and computations for solving locations) is performed at the client, the model is client-based.

Separation of metadata parts enables efficiency in storage and delivery. For example, during a session, the metadata of the content-level information 310 may be sent once, and only the interval level information 320 may be periodically updated. Similarly, one file containing the QoSInfo part 330 may be used for different intervals and for different content.

There are different ways to represent a collection of metadata, such as XML, pseudo-code, Session Description Protocol (SDP), and the like.

Embodiments of the present invention may use both XML and pseudo-code to represent the signaling syntax. XML syntax can be used for clients that support XLM profiles based on MPEG-21 and similar schemas. On the other hand, the pseudo-code syntax can be based on a "language" such as ISO base media file format and can be used in non-XML clients. In particular, the profile of the pseudo-code syntax may employ a parasitic module similar to the parsing module of file-format parsing. To design the syntax for this purpose, a table of common elements will be defined in the following embodiments, and the elements in each format will be represented.

These proposed syntaxes can also be expressed by any other languages.

A table of general syntax elements is described below.

In the following tables, the syntax elements are described hierarchically. That is, a child element appears in the column to the right of its parent element. "Leaf" - The level elements appear italic. The parent elements appear as bold letters. The parent element is represented by the corresponding XML type and file box.

In the column of occurrences, "0 ... N" means that the number of instances of the occurrences element can range from zero to "unbounded ". However, the minimum number of occurrences of zero means that the element may be optional (i.e., not present). The minimum number of occurrences of one or more means that the element is mandatory in the syntax.

Occurrences can be used in the same sense as cardinality.

In the type row, A represents an attribute and E represents an element. In the optionality line, M means mandatory and O means optional. In the attribute, M means mandatory, O means optional, OD means optional with default value, CM means conditionally mandatory. For an element, the element can be expressed as < minOccurs > ... < maxOccurs >. At this time, N represents unbounded.

 This meaning is the same in other tables of this specification.

In addition, the QoSInfo may more specifically be referred to as AdaptationInfo. Moreover, some elements have been revised to increase the flexibility of the syntax.

Table 1 below describes general information.

Number of occurrences Semantic XML syntax syntax
(Based on MPEG-21) Pseudo-code
(File format box) HttpStr One Top-level elements of signaling metadata for HTTP streaming HttpStreamingType (HTTP streaming type) 'htps' box GeneralInfo 0 ... N Contains general information about the described content GeneralInfoType (general information type) 'broad' box TimeScale 0 ... 1 The number of time units within a second.
This value is used with time-related elements when a time unit is not specified. integer (integer) unsigned int (unsigned integer) (32) LiveStartTime 0 ... 1 If there is no LiveStartTime element, the content is of type Vod.
The existence of the LiveStartTime element indicates that live content will be displayed in LiveStartTime's time value.
If the time value of LiveStartTime is 0, the display time is not known. dateTime unsigned int (64) Duration 0 ... 1 If present, indicates the duration of the content. Otherwise the duration is unknown. integer unsigned int (32) DefaultIntDuration 0 ... 1 If present, indicates the default duration of each interval of content. integer unsigned int (32) MinUpdateTime 0 ... 1 If present, indicates the minimum wait time before requesting the main description file again. integer unsigned int (32) ConsistentQoSInfo 0 ... 1 When True, the QoS information is the same as the whole content duration. Boolean (binary) flag of the box
(Flags in the box) DefaultContentLoc 0 ... 1 Provide the default location of the content. anyURI (any URI) string of URL
(A string of URLs) IntervalsRef 0 ... N Interval Provides a reference to a description containing one or more instances of an element.
One or more instances of the Interval element represent a sequence of consecutive interval (s). IntervalsRefType (Interval Reference Type) 'iref' box Interval 0 ... N Provide information on the interval of content.
Interval information can be included as an instance of the Interval element, and can be referenced by the IntervalsRef element. IntervalType (Interval Type) 'intv' box IntervalInfo 0 ... 1 Provide general information of interval. IntervalInfoType (interval information type) 'inti' box QoSInfoRef 0 ... 1 Provides a reference to the description represented by the QoSInfo element.
If there is a QosInfoRef element, the QoSInfo element should not be represented at the same level. dia: ReferenceType 'qref' box QoSInfo 0 ... 1 Provide information about alternatives to content, such as resource characteristics and quality / utility.
If there is a QoSInfo element, there is no QoSInfoRef element. QoSInfoType
(QoS information type) 'QoSi' box MappingInfoRef 0 ... 1 Provides a reference to the description represented by the MappingInfo element.
If there is a MappingInfoRef element, the MappingInfo element should not be represented at the same level. dia: ReferenceType 'mref' box MappingInfo 0 ... 1 Provide information about the locations of content alternatives.
If this information is not provided, the DefaultContentIntLoc (or DefaultContentLoc, if present) element can be used to retrieve the content.
If there is a MappingInfo element, there is no MappingINfoRef element. MappingInfoType
(Mapping information type) 'mapi' box NextIntervalsRef 0 ... 1 Provide a reference to the information of the next interval (s).
The information of the next interval (s) is an explanation that includes one or more instances of the interval element.
The information of the next interval is the description expressed by the Interval element.
By using the NextIntervalsRef element, the client does not need to reload the main description represented by the HttpStr element.
Within the current time window, only the last interval can contain the NextIntervalsRef element. IntervalsRefType, can be extended from dia: ReferenceType.
'nref' box PreviousIntervalsRef 0 ... 1 Provide a reference to the information of the previous interval (s).
The information of the next interval (s) is an explanation that includes one or more instances of the interval element.
The information of the next interval is the description expressed by the Interval element.
By using the PreviousIntervalsRef element, the client does not need to reload the main description represented by the HttpStr element.
Within the current time window, only the first interval can contain the NextIntervalsRef element. IntervalsRefType, can be extended from dia: ReferenceType.
'nref' box

Table 2 below describes the IntervalsRef, NextIntervalsRef, PreviousIntervalsRef, QoSInfoRef, MappingInfoRef a, and IntervalInfo elements.

Number of occurrences Semantic XML syntax syntax
(Based on MPEG-21) Pseudo-code
(File format box) QoSInfoRef,
MappingInfoRef Index One Indicates the order of the reference description or box (Interval, QoSInfo, MappingInfo) in the description file referenced by the following Location element (starting at 1). not applicable
(Not applicable) unsigned int (8) Location One Provides a reference to the description represented by Interval, QoSInfo, or MappingInfo. dia: uri element in ReferenceType string (representing url) IntervalInfo TimeScale 0 ... 1 The number of time units within a second. This value is used with time-related elements when a time unit is not specified.
The TimeScale element, if any, overrides the time scale provided by GeneralInfo. integer unsigned int (32) StartTime 0 ... 1 Indicates the start time of the interval. Duration 0 ... 1 Indicates the duration of the interval. integer unsigned int (32) DefaultFragDuration 0 ... 1 Indicates the default duration of fragments of the interval. (Last fragment exception) integer unsigned int (32) DefaultContentIntLoc 0 ... 1 Provide a default location for the content interval. anyURI type string Last 0 ... 1 If true, indicates the last interval of the content. boolean by flag
(With flag) IntervalsRef,
PreviousIntervalsRef
NextIntervalRef startTime The start time of the referenced sequence of intervals / periods relative to the start time of the content (LiveStartTime for live content and 0 for on-demand content). xs: duration
(xs: duration) AvailableTime 0 ... 1 The following description of the interval indicates the available time. This time is a relative time from the start time of the content. integer unsigned int (32) Index One Indicates the sequence (1-based) of the interval descriptions (or boxes) referenced in the description file referenced by the following Location element. not applicable unsigned int (8) Location One Interval Provides a reference to a description file containing descriptions. uri element in sx: anyURI type or dia: ReferenceType string (representing url) (express url)

Table 3 below describes the QoSInfo element.

Number of occurrences Semantic XML syntax syntax
(Based on MPEG-21) Pseudo-code
(File format box) QoSInfo One Provides information on a list of content alternatives, such as resource characteristics and quality / usability. Contains QoSInfoType containing a UtilityFunction of dia: AdaptiveQoSType
(dia: QoS information type including UtilityFunction of AdaptiveQoSType) 'QoSi' box ClassSchemeRef 0 ... 1 Provide a list of Classification Schemes.
Classification schemes provide semantics for some terms or names. dia: DescriptionMetadataType
(dia: description metadata type) 'csmr' box scheme 1 ... N Reference to classification scheme Attr. alias & href in dia: DescriptionMetadataType
(dia: Property alias and href in DescriptionMetadataType) a url string (One) Resource 0 ... N Each instance of the Resource element describes a property value of a certain resource type (e.g., bit rate) for a list of alternatives. Element Constraint of dia: UFDataType in DIA Utility-FunctionType
(Element constraint of dia: UF data type within DIA utility-function type) 'resi' box (2) AdaptationOperator 0 ... N Each instance of the AdaptationOperator element describes the values of some adaptation type (e.g., remove temporal layers), for a list of alternatives. dia: UFDataType 'adpo' box (3) Utility 0 ... N Each instance of the Utility element describes values within a certain quality / usability type (e.g., MOS) for a list of alternatives. dia: UFDataType 'util' box UtilityRank 0 ... 1 Describe the quality ranking for a list of alternatives. dia: UtilityRankType
(Usability ranking type) 'utir' box Value 1 ... N Indicates the quality / usability ranking of alternatives.
The number of instances of the Value element is equal to the number of alternatives. integer unsigned int (16)

Table 4 below shows the common semantics of (1) Resource, (2) AdaptationOperator and (3) Utility elements in Table 3.

Number of occurrences Semantic XML syntax syntax
(Based on MPEG-21) Pseudo-code
(File format box) QoSInfo One Provides information on a list of content alternatives, such as resource characteristics and quality / usability. Contains QoSInfoType containing a UtilityFunction of dia: AdaptiveQoSType
(dia: QoS information type including UtilityFunction of AdaptiveQoSType) 'QoSi' box ClassSchemeRef 0 ... 1 Provide a list of Classification Schemes.
Classification schemes provide semantics for some terms or names. dia: DescriptionMetadataType
(dia: description metadata type) 'csmr' box scheme 1 ... N Reference to classification scheme Attr. alias & href in dia: DescriptionMetadataType
(dia: Property alias and href in DescriptionMetadataType) a url string (One) Resource 0 ... N Each instance of the Resource element describes a property value of a certain resource type (e.g., bit rate) for a list of alternatives. Element Constraint of dia: UFDataType in DIA Utility-FunctionType
(Element constraint of dia: UF data type within DIA utility-function type) 'resi' box (2) AdaptationOperator 0 ... N Each instance of the AdaptationOperator element describes the values of some adaptation type (e.g., remove temporal layers), for a list of alternatives. dia: UFDataType 'adpo' box (3) Utility 0 ... N Each instance of the Utility element describes values within a certain quality / usability type (e.g., MOS) for a list of alternatives. dia: UFDataType 'util' box UtilityRank 0 ... 1 Describe the quality ranking for a list of alternatives. dia: UtilityRankType
(Usability ranking type) 'utir' box Value 1 ... N Indicates the quality / usability ranking of alternatives.
The number of instances of the Value element is equal to the number of alternatives. integer unsigned int (16) The elements (1), (2), (3) Semantics XML syntax syntax
(Based on MPEG-21) Pseudo-code
(File format box) Name One An identifier for a particular type of element.
If this identifier is not semantically defined by this embodiment, the following three elements are used to find the semantics of the identifier in the classification scheme. Att. 'iOPinRef', ref. a CS term (see 'iOPinRef' attribute, CS term) unsigned int (32) CSref_ind 0 ... 1 Points to the reference index of the classification scheme in the list provided by the ClassSchemeRef element. Not applicable unsigned int (16) LevelNum 0 ... 1 Indicates the number of levels. Not applicable unsigned int (16) LevelIndex 1 ... N Each instance of the LevelIndex element represents an index value at the level of the classification scheme. Not applicable unsigned int (16) Value 1 ... N A value of an alternative resource (adaptive operator or usability) type.
The number of instances of the Value element is equal to the number of alternatives. a component in dia: VectorDataType
(dia: a component in the vector data type) unsigned int (32)

Table 5 below shows mapping information.

Number of occurrences Semantic XML syntax syntax
(Based on MPEG-21) Pseudo-code
(File format box) MappingInfo 0 ... 1 MappingInfoType 'mapi'box AlterLocID 0 ... 1 Provide a location ID for each alternative described in QoSInfo.
If there is no AlterLocID element, the first position in the location list is used for all alternatives. dia: IntegerVectorType 'aloc' box Value 1 ... N Points to an alternate location ID.
The number of instances of this element is equal to the number of alternatives.
The nth instance of the Value element corresponds to the nth alternative of the QoSInfo description. integer unsigned int (16) ReqQoSPara 0 ... N Indicates the QoSInfo parameter that is put in the request (to the alternative) sent by the client to the server.
The parameter can be an instance of the Resource, AdaptationOperator, Utility, or UtilityRank element. ReqQoSParaType that extends dia: BooleanVectorType
(ReqQoSParaType that extends dia: BooleanVectorType) 'reqp' box RefIndex One Indicates an instance index / reference in the instance list of Resource, AdaptationOperator, Utility and UtilityRank elements. represented by attribute 'iOPinRef' that references an IOPin in QoSInfo
(Represented by the 'iOPinRef' attribute referencing IOPin in QoSInfo) unsigned int (16) All One When true, the parameter is requested for all alternatives and a ReqFlag that can be skipped. boolean flag ReqFlag 0 ... N Each instance of the ReqFlag element corresponds to an alternative.
When the value of ReqFlag is true, the request for the corresponding alternative has the parameters identified above. component of BooleanVectorType
(A component of BooleanVectorType) unsigned int (8) LocationList One Provides a list of locations for extracting content alternatives. LocationListType 'locl' box Location 1 ... N Provide location information. LocationType 'loca' box

The semantics of the Location elements may be further provided as shown in Table 6 below.

Number of occurrences Semantic XML syntax syntax
(DIA based) Pseudo-code
(MP4) Location 0 ... N LocationType
(Position type) 'loca' box LocID One Indicates the ID of the instance of the Location element. The location element is referenced by the AlterLocID. integer unsigned int (16) StrLocation 0 ... N And provides the position information of the stream of the content interval.
Each stream is provided by a stream URL or multiple fragment URLs. StrLocationType  'stlo' box FragNum 0 ... 1 Provide the number of fragments. integer unsigned int (16) StreamUrl 0 ... 1 Describes the URL of the stream. anyURI type string FragmentUrl 0 ... N Describe the URL of the fragment. The number of instances of the FragmentUrl element is the number of fragments. anyURI type string FragTime 0 ... 1 Provides the duration of the fragments. dia: VectorDataType  'frtm' box Value 1 ... N Indicates the duration of the fragment.
The number of instances of the Value element is the number of fragments. integer unsigned int (32) RandAccess 0 ... 1 Describes fragments that support random access. dia: VectorDataType  'rdac' box Value 1 ... N Indicates the sequence of random access fragments. integer unsigned int (16) MP2TSPara 0 ... 1 Additional parameters (other than URL) for locating the exact location of the content / program within the MPEG-2 TS stream are described. MP2TSParaType
(MP2TS parameter type) 'mp2p' box PID 0 ... N The values of the PIDs of the contents / programs in the MPEG-2 TS stream are described. dia: VectorDataType unsigned int (16) FragBoundaries 0 ... 1 Describes the boundaries of (virtual) fragments in the stream.
The number of instances of the FragBoundaries element is equal to the number of fragments in the stream.
Only one of the following types appears in the FragBoundaries instance. FragBoundariesType  'frbd' box MP2TSBoundary 0 ... N Parameters for detecting (virtual) fragment boundaries within the MPEG-2 TS stream are described.
If there are two instances of the MP2TSBoundary element, then the two instances are the boundaries of the beginning and end of the fragment.
If there is only one instance of the MP2TSBoundary element, then one instance is the start boundary. The end boundary is immediately before the start boundary of the next fragment. MP2TSBoundaryType
(MP2TS boundary type) 'mp2b' box ISOFileBoundary 1 ... 2 Describes parameters for detecting (virtual) fragment boundaries within a file based on the ISO base media file format.
If there are two instances of the ISOFileBoundary element, then the two instances are the boundaries of the beginning and end of the fragment.
If there is only one instance of the ISOFileBoundary element, then one instance is the start boundary. The end boundary is immediately before the start boundary of the next fragment. ISOFileBoundaryType
(ISO file boundary type) 'isfb' box ByteRanges One Describes the byte ranges that identify the part / fragment of the file.
The parameters provided by the ByteRanges element can be used for byte range options in an HTTP request. ByteRangesTypes
(Byte ranges type) 'brag' box

The semantics of the MP2TSBoundary, ISOFileBoundary, and ByteRanges elements may be further provided as shown in Table 7 below.

Number of occurrences Semantic XML syntax syntax
(DIA based) Pseudo-code
(MP4) MP2TSBoundary MP2TSBoundaryType
(MP2TS boundary type) 'mp2b' box PCR_PID One Describes the PID that carries the PCR of the associated content / program. integer unsigned int (16) PCR_base One Describe the value of the PCR base field long unsigned int (40) PCR_ext One Describe the value of the PCR extension field. integer unsigned int (16) Appearance One Describes the appearance order (e.g., first and second) of the TS packet including the PCR value identified by the above two factors.
When there is resetting / discontinuity of the PCR, the PCR value may appear more than once during the interval. integer unsigned int (16) Media_PID 1 ... N Describes the PID of the program's media (eg, video).
The number of Media_PID elements is equal to the number of media in the program / content. integer unsigned int (16) Media_Offset 1 ... N Describe the offset (in the TS packet of the same media PID) from the identified PCR packet to the first media packet of the fragment.
The nth instance of Media_Offset is associated with the nth instance of Media_PID. integer unsigned int (16) ISOFileBoundary ISOFileBoundaryType
(ISO file boundary type) 'isfb' box SequenceNo One Describes the sequence number provided in the mfhd box.
The mfhd box defines the fragment of the MP4 file.
A SequenceNo value of 0 indicates the start of the file. integer unsigned int (16) ByteRanges ByteRangesType
(Byte range type) 'brag' box Start 1 ... N Describes the start value of the byte range.
A value of '-1' means that there is no value in the HTTP request. integer unsigned int (32) End 1 ... N Describes the end value of the range of the vital.
A value of '-1' means that there is no value in the HTTP request.
Start-End instances are in pairs. The nth instance of End is associated with the nth instance of Start. integer unsigned int (32) Media _ PID 0 ... N Describes the PID of the media (e.g., video) to be extracted from the byte range of the above Start-End pair.
Media _ PID element is used when the segment (segment) of the byte range of MPEG-2 TS, need not be all the PID is transmitted. integer unsigned int (16)

The client request is described below.

The signaling of the metadata obtained by the client may comprise different parts or levels of the signaling information. Thus, a request from a client to a server may include different levels of parameters of detail.

The client's main parameters are URIs, and the main parameters are associated with the query part.

We review three major scenarios below.

1) Server-based scenario

In this case, the metadata provided from the server to the client is composed of the general content information 310 and the general interval information 320.

For the URI of the requested content, DefaultContentIntLoc (if not, DefaultContentIntLoc) is used. In order to enable the client to request a particular fragment of content, the following parameters a) and b) are defined within the query portion (of the request of step 140).

a) "fragno": Within the interval above, the order value of the fragment

b) "fragti": Within the above interval, the start time of the fragment

For example, the request URI may be "HTTP://server.com/file.mp4?fragno=5&quot ;.

2) Distributed scenarios

In this case, the metadata provided from the server to the client includes the general content information 310, the general interval information 320, and the QoS information 330.

In addition to the above parameters, the following QoS-related parameters a) to c) are defined in the query part (of the request of step 140) to enable the client to request a suitable alternative.

a) "alter" is the order value of the alternative. Depending on the order value of the alternatives, an alternative appears within the QoS information.

b) "oper1", "oper2", ... "operN": "oper i " carries the value of the ith adaptation operation appearing in the QoS information.

c) "res1", "res2", ... "resN": "res i " carries the value of the i-th resource represented in the QoS information.

Within one request, only one of the above three options may be used.

Better intelligibility and interoperability special parameter names can be defined, along with typical adaptation operators and resource types.

The adaptation operators are as follows a) to e).

a) Audio layers (audiolayers): Indicates the number of scalable audio layers to be discarded.

b) Temporalayers: The number of temporal layers of scalable video to be discarded.

c) Spatiallayers: the number of spatial layers of extensible video to be discarded.

d) qualitylayers: refers to the number of spatial layers of extensible video to be discarded.

e) prioritylayers: indicates the number of priority layers of extensible video to be discarded.

The resource types are as follows a) to d).

a) bitrate: the average bit rate (in Kbps) of the requested alternative.

b) Vertresolution: Indicates the vertical resolution of the requested alternative.

c) Horizontal resolution: indicates the horizontal resolution of the requested alternative.

d) Frame rate: indicates the frame rate of the requested alternative.

Using these predefined parameters, "http://server.com/file.mp4?fragno=5&bitrate=550" can be an example of a URI request based on a bitrate.

3) Client-based scenario

In this case, the metadata provided from the server to the client includes general contents, general interval information, QoS information, and mapping information.

The QoS-related parameters used in the request are indicated by the ReqQoSPara part of the QoSInfo metadata. If the RefIndex of ReqQoSPara is 0 or null, the "alter" parameter is used instead of the other options.

If there is no ReqQoSPara in the QoSInfo metadata, QoS-related parameters are not used. The alternatives in this case are implied by the locations of MappingInfo.

The URI of the content comes from the rich description of MappingInfo. When the content / program is transported within the MPEG-2 TS stream, one or more PIDs are used to locate the content within the stream.

The following parameters 1) through 3) for the query part (of the request of step 140) may be used when additional information is provided to detect fragment boundaries.

1) For MPEG-2 TS boundaries, Apperance, PCR_PID, PCR_base, PCR_ext, Media_PID, and Media_Offset

2) For ISO media file boundaries, SequenceNo

3) For files considered as raw byte-sequences, Start and End

The semantics of these parameters are provided in the semantics of the FragBoundaries element.

Start-End pairs can be used by the scope header of the HTTP request message. For example, if {(Start = 0, End = 99); (Start = 200, End = 299)}, the header is "Range: bytes = 0-99,200-299 ".

In the following, a syntax representation of the XML format is described. In the following, the presentation of the above syntax elements is provided in XML format. The semantics of each element can be traced back within Tables 1 to 7 above.

Some elements may be extensions of some types defined within the MPEG-21 DIA. Some elements may take some types defined within the MPEG-21 DIA.

Table 8 below is a syntax representation using the XML format of HTTPStreamingType.

<complexType name = "HTTPStreamingType">
<complexContent>
<extension base = "dia: DIADescriptionType">
<sequence>
<element name = "GeneralInfo" type = "GeneralInfoType" minOccurs = "0"/>
<choice minOccurs = "0" maxOccurs = "unbounded">
<element name = "IntervalsRef" type = "IntervalsRefType"/>
<element name = "Interval" type = "IntervalType"/>
</ choice>
</ sequence></complexContent>
</ complexType>

Table 9 below is a syntax representation using the XML format of GeneralInfoType.

<complexType name = "GeneralInfoType">
<complexContent>
<extension base = "dia: DIADescriptionType">
<sequence>
<element name = "TimeScale" type = "integer" minOccurs = "0"/>
<element name = "LiveStartTime" type = "dateTime" minOccurs = "0"/>
<element name = "Duration" type = "integer" minOccurs = "0"/>
<element name = "DefaultIntDuration" type = "integer" minOccurs = "0"/>
<element name = "MinUpdateTime" type = "integer" minOccurs = "0"/>
<element name = "ConsistentQoSInfo" type = "boolean" minOccurs = "0"/>
<element name = "DefaultContentLoc" type = "anyURI" minOccurs = "0"/>
</ sequence>
</ extension>
</ complexContent>
</ complexType>

Table 10 below is a syntax representation using the XML format of IntervalRefType.

<complexType name = "IntervalsRefType">
<complexContent>
<extension base = "dia: ReferenceType">
<sequence>
<element name = "AvaliableTime" type = "integer" minOccurs = "0"/>
</ sequence>
<attribute name = "startTime" type = "xs: duration" use = "optional"/>
</ extension>
</ complexContent>
</ complexType>

Table 11 below is a syntax representation using XML format of IntervalType.

<complexType name = "IntervalType">
<complexContent>
<extension base = "dia: DIADescriptionType">
<sequence>
<element name = "IntervalInfo" type = "IntervalInfoType" minOccurs = "0"/>
<choice minOccurs = "0">
<element name = "QoSInfo" type = "QoSInfoType"/>
<element name = "QoSInfoRef" type = "dia: ReferenceType"/>
</ choice>
<choice minOccurs = "0">
<element name = "MappingInfo" type = "MappingInfoType"/>
<element name = "MappingInfoRef" type = "dia: ReferenceType"/>
</ choice>
<element name = "PreviousIntervalsRef" type = "IntervalsRefType" minOccurs = "0"/>
<element name = "NextIntervalsRef" type = "IntervalsRefType" minOccurs = "0"/>
</ sequence>
</ extension>
</ complexContent>
</ complexType>

Table 12 below is a syntax representation using the XML format of IntervalInfoType.

<complexType name = "IntervalInfoType">
<sequence>
<element name = "TimeScale" type = "integer" minOccurs = "0"/>
<element name = "StartTime" type = "dateTime" minOccurs = "0"/>
<element name = "Duration" type = "integer" minOccurs = "0"/>
<element name = "DefaultFragDuration" type = "integer" minOccurs = "0"/>
<element name = "DefaultContentIntLoc" type = "anyURI" minOccurs = "0"/>
<element name = "Last" type = "boolean" minOccurs = "0"/>
</ sequence>
</ complexType>

Table 13 below is a syntax representation using the XML format of ISOFileBoundaryType and ByteRangesType.

<complexType name = "ISOFileBoundaryType">
<sequence>
<element name = "SequenceNo" type = "integer" maxOccurs = "unbounded"/>
</ sequence>
</ complexType>
<complexType name = "ByteRangesType">
<sequence maxOccurs = "unbounded">
<element name = "Start" type = "integer"/>
<element name = "End" type = "integer"/>
<element name = "Media_PID" type = "integer" minOccurs = "0"/>
</ sequence>
</ complexType>

In the following, the syntax representation of the MP4 pseudo-code format will be described. In the following, the representation of the above syntax elements is provided in the MP4 pseudo-code.

Table 14 below is a syntax representation using the MP4 pseudo-code of the HTTPStreamingBox.

HTTPStreamingBox
Box Type: 'htps'
Container: Signaling file
Mandatory: Yes
Quantity: One
Aligned (8) class HTTPStreamingBox extends Box ('htps') {
}

Figure 4 illustrates the detection of virtual boundaries within an MPEG-2 TS according to an example of the present invention.

In the TS stream, a PCR packet of a given program is carried with a fixed PID (i.e., PCR_PID) and inserted at least every 100 ms.

PCR packets (with increasing values) can be considered as program anchor points. On the other hand, each media in the program may be transported by packets of a given PID (i.e., Media_PID).

Thus, the fragment boundary of the media stream can be defined or identified by 1) a specific anchor point and 2) an offset from the anchor to a packet at the border.

The offset can be counted by packets of the same Media_PID.

Sometimes PCR values can be reset (discontinuous). In this case, if there is more than one PCR packet of the same PCR value in the interval, the order of appearance of the PCR packet used as the anchor is covered.

The sourceURL attribute can be changed from required to optional. This is because the baseURL already provides the complete URL. sourceURL may not be required.

The use of multi-byte ranges provides flexibility in downloading "virtual segments ". For example, a segment of a low frame rate (which can be used in trickmode) can be extracted on-the-fly from a stream or a circle segment.

In addition, to support the use of multiple URLs for Representation, the following variant may be applied to the schema of 3GPP adaptive HTTP streaming.

In the following, multiple locations for the same resource / content are described.

Each level of description (top-level, Period level, Representation level) provides only a single base URL for constructing absolute URLs from the description.

At each level of description, multiple base URLs may be provided. Multiple base URLs signal availability of resources at multiple locations.

Depending on the actual location of the client, the client may select one or more base URLs in the procedure for extracting resources.

These variations can be implemented in different ways. One approach is to use an additional attribute called "morebaseURLs" or an element called "BaseURLs".

These attributes or elements may be strings consisting of multiple (base) URLs. The string may be separated by some special characters, such as ";" (i.e., semicolon and space characters).

If any semicolon or whitespace character appears in the URL, semicolons or whitespace characters can be encoded by the rules of RFC 2616.

A lower description level morebaseURL attribute (or BaseURLs element) overrides the same attribute (element) at a higher description level.

For clarity, the morebaseURLs attribute and the BaseURLs element may be restricted to mutual exclusion. That is, there can be only one type in the entire description.

When each instance provides a base URL, another approach is to use the MoreBaseURL element of any URI type with multiple instances.

These different approaches are merely an example of the idea of providing multiple base URLs. This idea can be implemented in many different ways or in different languages.

The following describes the multiple locations for the author / content components.

The resource / content may be divided into one or more components / streams. Each of the one or more components / streams is delivered from a location. This transfer can be supported by allowing multiple instances of the UriTemplate element or a set of Url elements in the SegmentInfoType. Change within SegmentInfoType "<xs: choice maxOccurs =" unbounded ">" can be used for this purpose.

The order of appearance of a UrlTemplate instance or a Url set instance can indicate the importance of its "location / stream". More important locations may appear before less important locations. For example, the Video Representation may be composed of two streams (a spatial base layer and a spatial enhancement layer). Each is passed from the location described by UrlTemplate. Next, the first instance of the UrlTemplate becomes the location for the spatial base layer.

Furthermore, multiple instances of InitialisationSegmentURL may be allowed. The nth instance of InitialisationSegmentURL corresponds to the nth instance of location (by UrlTemplate element or Url element set).

If there is only one instance of InitialisationSegmentURL, then the instance can be used for all locations.

Tables 15 to 19 below show the schema of 3GPP AdaptiveHTTPStreaming.

<? xml version = "1.0" encoding = "UTF-8"?>
<xs: schema targetNamespace = "urn: 3GPP: ns: PSS: AdaptiveHTTPStreamingMPD: 2009"
attributeFormDefault = "unqualified"
elementFormDefault = "qualified"
xmlns: xs = "http://www.w3.org/2001/XMLSchema"
xmlns = "urn: 3GPP: ns: PSS: AdaptiveHTTPStreamingMPD: 2009">
<xs: annotation>
<xs: appinfo> Media Presentation Description </ xs: appinfo>
<xs: documentation xml: lang = "en">
This Schema defines 3GPP Media Presentation Description!
</ xs: documentation>
</ xs: annotation><! - MPD: main element ->
<xs: element name = "MPD" type = "MPDtype"/>

<! - MPD Type ->
<xs: complexType name = "MPDtype">
<xs: sequence>
<xs: element minOccurs = "0" name = "ProgramInformation" type = "ProgramInformationType"/>
<xs: choice maxOccurs = "unbounded">
<xs: element name = "Period" type = "PeriodType"/>
<xs: element name = "PeriodsRef" type = "PeriodsRefType"/>
</ xs: choice>
<xs: element minOccurs = "0" name = "BaseUrls" type = "xs: string"/>
<xs: element minOccurs = "0" maxOccurs = "unbounded" name = "MoreBaseUrl" type = "xs: anyURI"/>
<xs: any namespace = "## other" processContents = "lax" minOccurs = "0" maxOccurs = "unbounded"/>
</ xs: sequence>
<xs: attribute default = "OnDemand" name = "type" type = "PresentationType"/>
<xs: attribute name = "availabilityStartTime" type = "xs: dateTime"/>
<xs: attribute name = "availabilityEndTime" type = "xs: dateTime"/>
<xs: attribute name = "mediaPresentationDuration" type = "xs: duration"/>
<xs: attribute name = "minimumUpdatePeriodMPD" type = "xs: duration"/>
<xs: attribute name = "minBufferTime" type = "xs: duration" use = "required"/>
<xs: attribute name = "timeShiftBufferDepth" type = "xs: duration"/>
<xs: attribute name = "baseUrl" type = "xs: anyURI"/>
<xs: attribute name = "morebaseUrls" type = "xs: string"/>
<xs: anyAttribute namespace = "## other" processContents = "lax"/>
</ xs: complexType>

<xs: complexType name = "PeriodsRefType">
<xs: sequence>
<xs: element name = "Location" type = "xs: anyURI"/>
</ xs: sequence>
<xs: attribute name = "startTime" type = "xs: duration"/>
<xs: attribute name = "duration" type = "xs: duration"/>
<xs: attribute name = "availableTime" type = "xs: duration"/>
</ xs: complexType>

<! - Type of presentation - live or on-demand ->
<xs: simpleType name = "PresentationType">
<xs: restriction base = "xs: string">
<xs: enumeration value = "OnDemand"/>
<xs: enumeration value = "Live"/>
</ xs: restriction>
</ xs: simpleType>
<! - Period of a presentation ->
<xs: complexType name = "PeriodType">
<xs: sequence>
<xs: element minOccurs = "0" name = "SegmentInfoDefault" type = "SegmentInfoDefaultType"/>
<xs: element maxOccurs = "unbounded" name = "Representation" type = "RepresentationType"/>
<xs: element minOccurs = "0" name = "PreviousPeriodsRef" type = "xs: PeriodsRef"/>
<xs: element minOccurs = "0" name = "NextPeriodsRef" type = "xs: PeriodsRef"/>
<xs: any namespace = "## other" processContents = "lax" minOccurs = "0" maxOccurs = "unbounded"/>
</ xs: sequence>
<xs: attribute name = "start" type = "xs: duration"/>
<xs: attribute default = "false" name = "segmentAlignmentFlag" type = "xs: boolean"/>
<xs: attribute default = "false" name = "bitStreamSwitchingFlag" type = "xs: boolean"/>
<xs: attribute default = "false" name = "lastPeriodFlag" type = "xs: boolean"/>
<xs: anyAttribute namespace = "## other" processContents = "lax"/>
</ xs: complexType>

<! - Program information for presentation ->
<xs: complexType name = "ProgramInformationType">
<xs: sequence>
<xs: element minOccurs = "0" name = "Title" type = "xs: string"/>
<xs: element minOccurs = "0" name = "Source" type = "xs: string"/>
<xs: element minOccurs = "0" name = "Copyright" type = "xs: string"/>
<xs: any namespace = "## other" processContents = "lax" minOccurs = "0" maxOccurs = "unbounded"/>
</ xs: sequence>
<xs: attribute name = "moreInformationURL" type = "xs: anyURI"/>
<xs: anyAttribute namespace = "## other" processContents = "lax"/>
</ xs: complexType>

<! - Default Segment access information ->
<xs: complexType name = "SegmentInfoDefaultType">
<xs: sequence>
<xs: element minOccurs = "0" name = "BaseUrls" type = "xs: string"/>
<xs: element minOccurs = "0" maxOccurs = "unbounded" name = "MoreBaseUrl" type = "xs: anyURI"/>
<xs: any namespace = "## other" processContents = "lax" minOccurs = "0" maxOccurs = "unbounded"/>
</ xs: sequence>
<xs: attribute name = "baseURL" type = "xs: anyURI"/>
<xs: attribute name = "morebaseUrls" type = "xs: string"/>
<xs: attribute name = "duration" type = "xs: duration"/>
<xs: attribute name = "sourceUrlTemplatePeriod" type = "xs: string"/>
<xs: anyAttribute namespace = "## other" processContents = "lax"/>
</ xs: complexType>
<! - A Representation of the presentation content for a specific Period ->
<xs: complexType name = "RepresentationType">
<xs: sequence>
<xs: element name = "SegmentInfo" type = "SegmentInfoType"/>
<xs: element minOccurs = "0" name = "ContentProtection" type = "ContentProtectionType"/>
<xs: element minOccurs = "0" name = "TrickMode" type = "TrickModeType"/>
<xs: element minOccurs = "0" maxOccurs = "unbounded" name = "Quality" type = "QualityType"/>
<xs: any namespace = "## other" processContents = "lax" minOccurs = "0" maxOccurs = "unbounded"/>
</ xs: sequence>
<xs: attribute name = "bandwidth" type = "xs: unsignedInt" use = "required"/>
<xs: attribute default = "0" name = "group" type = "xs: unsignedInt"/>
<xs: attribute name = "width" type = "xs: unsignedInt"/>
<xs: attribute name = "height" type = "xs: unsignedInt"/>
<xs: attribute name = "lang" type = "xs: string"/>
<xs: attribute name = "mimeType" type = "xs: string" use = "required"/>
<xs: attribute default = "false" name = "startWithRAP" type = "xs: boolean"/>
<xs: attribute name = "qualityRanking" type = "xs: unsignedInt"/>
<xs: attribute name = "requestPara" type = "xs: string"/>
<xs: anyAttribute namespace = "## other" processContents = "lax"/>
</ xs: complexType>

<xs: complexType name = "QualityType">
<xs: sequence>
<xs: any namespace = "## other" processContents = "lax" minOccurs = "0" maxOccurs = "unbounded"/>
</ xs: sequence>
<xs: attribute name = "name" type = "xs: QualityNameType"/>
<xs: attribute name = "value" type = "xs: float"/>
</ xs: complexType>

<xs: simpleType name = "QualityNameType">
<xs: restriction base = "xs: string">
<xs: enumeration value = "PSNR"/>
<xs: enumeration value = "MOS"/>
<xs: enumeration value = "ODG"/>
<xs: enumeration value = "DI"/>
</ xs: restriction>
</ xs: simpleType>
<! - Segment access information ->
<xs: complexType name = "SegmentInfoType">
<xs: sequence>
<xs: element minOccurs = "0" name = "BaseUrls" type = "xs: string"/>
<xs: element minOccurs = "0" maxOccurs = "unbounded" name = "MoreBaseUrl" type = "xs: anyURI"/>
<xs: element minOccurs = "0" maxOccurs = "unbounded" name = "InitialisationSegmentURL" type = "UrlType"/>
<xs: choice maxOccurs = "unbounded">
<xs: element minOccurs = "0" name = "UrlTemplate" type = "UrlTemplateType"/>
<xs: sequence>
<xs: element maxOccurs = "unbounded" name = "Url" type = "UrlType"/>
<xs: any namespace = "## other" processContents = "lax" minOccurs = "0" maxOccurs = "unbounded"/>
</ xs: sequence>
<xs: any namespace = "## other" processContents = "lax" minOccurs = "0" maxOccurs = "unbounded"/>
</ xs: choice>
</ xs: sequence>
<xs: attribute name = "baseURL" type = "xs: anyURI"/>
<xs: attribute name = "morebaseUrls" type = "xs: string"/>
<xs: attribute name = "duration" type = "xs: duration"/>
<xs: attribute name = "randAccess" type = "xs: string"/>
<xs: anyAttribute namespace = "## other" processContents = "lax"/>
</ xs: complexType>

<! - A Segment URL ->
<xs: complexType name = "UrlType">
<xs: sequence>
<xs: any namespace = "## other" processContents = "lax" minOccurs = "0" maxOccurs = "unbounded"/>
</ xs: sequence>
<xs: attribute name = "sourceURL" type = "xs: anyURI" use = "optional"/>
<xs: attribute name = "range" type = "xs: string"/>
<xs: anyAttribute namespace = "## other" processContents = "lax"/>
</ xs: complexType>

<! - A URL template ->
<xs: complexType name = "UrlTemplateType">
<xs: sequence>
<xs: any namespace = "## other" processContents = "lax" minOccurs = "0" maxOccurs = "unbounded"/>
</ xs: sequence>
<xs: attribute name = "sourceURL" type = "xs: anyURI"/>
<xs: attribute name = "id" type = "xs: string"/>
<xs: attribute default = "1" name = "startIndex" type = "xs: unsignedInt"/>
<xs: attribute name = "endIndex" type = "xs: unsignedInt"/>
<xs: anyAttribute namespace = "## other" processContents = "lax"/>
</ xs: complexType>
<! - Gives information about the content protection ->
<xs: complexType name = "ContentProtectionType">
<xs: sequence>
<xs: element minOccurs = "0" name = "SchemeInformation" type = "xs: string"/>
<xs: any namespace = "## other" processContents = "lax" minOccurs = "0" maxOccurs = "unbounded"/>
</ xs: sequence>
<xs: attribute name = "schemeIdUri" type = "xs: anyURI"/>
<xs: anyAttribute namespace = "## other" processContents = "lax"/>
</ xs: complexType>

<! - Gives information about trick mode ->
<xs: complexType name = "TrickModeType">
<xs: sequence>
<xs: any namespace = "## other" processContents = "lax" minOccurs = "0" maxOccurs = "unbounded"/>
</ xs: sequence>
<xs: attribute name = "alternatePlayoutRate" type = "xs: string"/>
<xs: anyAttribute namespace = "## other" processContents = "lax"/>
</ xs: complexType>

</ xs: schema>

5 is a structural diagram of a terminal 100 according to an embodiment of the present invention.

The control unit 510 performs steps 130 and 140. [ That is, the control unit 510 processes the metadata for the interval, and selects the fragment suitable for the interval based on the process

The transceiver 520 performs step 120, step 140 and step 150. That is, the transceiver 520 receives the metadata of the interval of the content from the server 110, requests the server for the appropriate fragment for the interval, and receives the fragment from the server.

6 is a structural diagram of a terminal 100 according to an embodiment of the present invention.

The terminal 100 may include an access engine 610 and a media engine 620.

The access engine 610 may be a DASH access engine.

The access engine 610 may receive metadata (e.g., MPD) from the server 110.

The access engine 610 may configure the requests and issue the configured requests to the server 110. The access engine 610 may receive media (a presenter, segments or portions of segments) from the server 110. The access engine may request a segment of media using the URL of the segment.

The access engine 610 may receive segments of the media based on the information provided by the metadata. Here, each period may include one or more groups, each group may include one or more representations of the media, and each presentation may include one or more segments.

The access engine 610 provides media to the media engine 620. The access engine 610 may decode the data of the media contained within the segments.

The output of the access engine 610 is stored in the media (or media) of an MPEG container (e.g., ISO / IEC 14492-12 ISO Base Media File Format or ISO / IEC 13818-2 MPEG-2 Transport Stream) &Lt; / RTI &gt; In addition, the output of the access engine 610 may include timing information to map the internal timing of the media to the timeline of the media presentation.

The media engine 620 plays the provided media. That is, the media engine 620 can receive the data of the media from the access engine and output the media. The media engine 620 may output the media using the data and timing information of the media output from the access engine 610. [

The technical contents according to one embodiment of the present invention described above with reference to Figs. 1 to 5 can be applied to this embodiment as it is. Therefore, a more detailed description will be omitted below.

The method according to an embodiment of the present invention can be implemented in the form of a program command which can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions recorded on the medium may be those specially designed and configured for the present invention or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Magneto-optical media, and hardware devices specifically configured to store and execute program instructions such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. This is possible.

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

100: terminal
110: Server

Claims (2)

A method of providing a media content to be performed by a server,
Receiving a request for media content based on media presentation description (MPD) from a client;
Providing a segment of media content to the client in streaming form in response to the request
Lt; / RTI &gt;
Wherein the media information comprises at least one period,
Wherein the period comprises one or more groups,
The group comprising one or more representations,
Wherein the representation comprises one or more segments,
Wherein the URL of the segment is associated with a base URL element. A media content providing method performed by a client,
Obtaining a media presentation description (MPD) for requesting media content;
Delivering a request for media content to the server based on the media information
Receiving a segment of media content in streaming form from the server
Lt; / RTI &gt;
Wherein the media information comprises at least one period,
Wherein the period comprises one or more groups,
The group comprising one or more representations,
Wherein the URL of the segment is associated with a base URL element.

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