IEEE Std 1857.7 pdf free download

IEEE Std 1857.7 pdf free download.Adaptive Streaming.
For the purposes of this document, the following terms and definitions apply. The IEEE Standards Dicuonarv Online should be consulted for terms not defined in this clause.4
adaptation set: Set of interchangeable encoded versions of one or several media content components.
authentication tag: Cryptographic checksum of data, to discover unexpected error or intended tampering.
bitstream switching segment: Segment that, if present, contains essential data to switch to the representation to which it is assigned.
continuous media: Media with an inherent notion of time, lbr example. speech, audio, video, timed text or timed metadata.
crypto period: Number of consecutive segments encrypted with the same key and initialization vector.
earliest presentation time (EPT): Smallest presentation time of any access unit of a media segment for a media stream.
encryption system: System encrypting media segments with keys provided by key system.
HTTP-URL: Uniform Resource Locator beginning with http:// or https://.
initialization segment: Segment containing metadata that is necessary to present the media streams encapsulated in media segments.
key system: System providing keys to encrypt media segments.
media content: One media content period or a contiguous sequence of media content periods.
media presentation description (MPD): Formalized description for a media presentation for the purpose of providing a streaming service.
media presentation tinwline: Concatenation of the timeline of all periods which itself is common to all representations in the period.
media presentation: Collection of data that establishes a presentation of media content.
5. Conventions
The following naming conventions apply in this standard.
Elements in an Extensible Markup Language (XML) document are identified by an uppercase first letter and in boldface, e.g., Element. To express that an element Element I is contained in another element Llement2, one may write Element2.Flementl. If an element’s name consists of two or more combined words, camel-casing is typically used, e.g., lmportantKlement. Elements may be present either exactly once or with the minimum and maximum occurrence defined by <minOccurs> … <maxOccurs>.
— Attributes in an XML document arc identified by a lowercase first letter as well as by being preceded by a ‘‘ (‘hat” sign), e.g., @‘attribute. To point to a specific attribute @attribute contained in an element Element, one may write Elementu attribute. If an attribute’s name consists of two or more combined words, camel-casing is typically used after the first word, e.g., @vcrylmportantAttribute. Attributes may be assigned a status in the XML as mandatory (M), optional (0), optional with default value (OD), and conditionally mandatory (CM).
— Namespace qualification of elements and attributes is used in accordance with XML standards, in the form of namespacc:Element or @namespace:attributc. Thc fully qualified namespacc will be provided in the schema fragment associated with the declaration.
Variables defined in the context of this standard are specifically highlighted with italics, e.g..
hiternal Variable.
Structures that are defined as part of the hierarchical data model are identified by an uppercase first letter, e.g.. Period, Adaptation Set, Representation, Segment.
6. Architecture
The architecture of Audio and Video Coding Standard Adaptive Streaming over HTTP (shortened as AVS-AS) is illustrated in Figure 1. AVS-AS mainly specifies the formats of media presentation description (MPD) (a modified version of the MPD defined in ISO/IEC 23OO9-l) and segment for adaptive streaming over IITTP.IEEE Std 1857.7 pdf download.