ISO/IEC 23001-13:2019 情報技術— MPEGシステム技術—パート13：メディアオーケストレーション | ページ 6

3.1

content

media data

data (3.3) that can be rendered, including audio, video, text, graphics, images, haptic and tactile information

Note 1 to entry: This data can be timed or non-timed.

3.2

controller

elementary function that controls one or more other elements, outputs control data (3.5) and can receive control data

3.3

data

bytes of information that are carried, processed or stored

3.4

timed data

data (3.3) that has an intrinsic timeline (3.25)

3.5

control data

data (3.3) exchanged for messaging and control

3.6

metadata

data (3.3) about other data that cannot be rendered independently and can affect rendering, processing or orchestration of the associated media data (3.1)

3.7

timed metadata

metadata (3.6) that has an intrinsic timeline (3.25)

3.8

orchestration data

data (3.3) that orchestrates any number of timed data (3.4) streams

Note 1 to entry: Orchestration data itself can also be timed data.

3.9

device

physical entity that can embody a number of elementary functions

3.10

m-processor

media processor

elementary function that can process media data (3.1) and/or metadata (3.6) , that can receive media data and/or metadata, that can optionally receive orchestration data (3.8) , that can output media data, metadata or both, and that can optionally exchange control data (3.5)

3.11

media orchestration

orchestration of media and metadata (3.6) capture, processing and presentation involving multiple devices (3.9)

3.12

media orchestration session

coherent application context that includes media capture and/or media processing and/or media rendering

3.13

media stream

timed media data (3.1)

3.14

mos more

mean opinion score of the subjective quality of a piece of timed media data (3.1)

3.15

sink

elementary function that can receive media data (3.1) , and optionally orchestration data (3.8) and/or metadata (3.6) , can present the media data, can optionally output metadata and can optionally exchange control data (3.5)

3.16

source

elementary function that can output media data (3.1) and/or metadata (3.6) and can optionally exchange control data (3.5)

3.17

timestamp

number that is used to identify an audio sample, video frame or metadata (3.6) sample

Note 1 to entry: The meaning of the term “timestamp” depends on the context. Within the MPEG context, the term is usually used as a single number to identify a point on the timeline of an MPEG-2 transport stream or within an ISOBMFF file. In the context of DVB-CSS (ETSI TS 103 286 02), the term “timestamp” is used to provide an association between a wall clock time and a point on a certain media timeline. This document uses the “dvb-css” prefix to flag where the DVB-CSS (ETSI TS 103 286 02) notion of timestamp is used.

3.18

dvb-css timestamp

pair of two values each of which represents a time value on a timeline such that the two-time values correspond to the same moment in time

[SOURCE: ETSI TS 103 286 02:2017, 3.1]

3.19

dvb-css control timestamp

dvb-css timestamp (3.18) representing the time (in relation to the wall clock) at which a synchronization client (3.24) is recommended to present a particular point in time (in relation to the synchronization timeline (3.25) ) of its timed data (3.4)

[SOURCE: ETSI TS 103 286 02:2017, 3.1, modified — «timed content» has been replaced with «timed data» and the note has been deleted]

3.20

dvb-css correlation timestamp

time values on two or more timelines (3.25) that correlate with each other

[SOURCE: ETSI TS 103 286 02:2017, 3.1, modified — «ore more” has been added and the note has been deleted]

3.21

dvb-css earliest presentation timestamp

dvb-css timestamp (3.18) representing the earliest time (in relation to the wall clock) at which a synchronization client (3.24) believes it can present a particular point in time of its timed data (3.4)

[SOURCE: ETSI TS 103 286 02:2017, 3.1, modified — “(in relation to the Synchronization Timeline) of its Timed Content” has been replaced with “of its timed data” and the note has been deleted]

3.22

user

human that uses one or more device(s) (3.9) and/or service(s)

Note 1 to entry: A user can be a producer and consumer of media, and both at the same time.

3.23

media synchronization application server

elementary function that coordinates the process of obtaining a shared agreement on the progress of timelines (3.25) among all synchronization clients (3.24)

Note 1 to entry: This is for the purpose of enabling the synchronization clients to present timed data simultaneously with respect to each other.

[SOURCE: ETSI TS 103 286 02:2017, 3.1]

3.24

synchronization client

elementary function that aligns its presentation of timed data (3.4) with other synchronization clients by communicating with a media synchronization application server (3.23)

[SOURCE: ETSI TS 103 286 02:2017, 3.1, modified — “wishes to align” has been replaced with “aligns” and “timed content” has been replaced with “timed data”]

3.25

timeline

reference frame for describing time, represented as a linear scale against which time can be measured for a particular system

Note 1 to entry: This could manifest in various ways, such as: as a local oscillator, the progress of a broadcast or the time position within an item of media content.

[SOURCE: ETSI TS 103 286 02:2017, 3.1]

3.26

timeline correlation

correlation between two timelines (3.25)

[SOURCE: ETSI TS 103 286 02:2017, 3.1]

3.27

wall clock

linear monotonic clock that is not assumed to represent real date and time

Note 1 to entry: The wall clock is intended for sharing between two or more entities for the purposes of having a common synchronized time reference frame.

Note 2 to entry: DVB-CSS (ETSI TS 103 286 02) wall clock is NOT a “UTC-type date&time”. It has a random offset and it has no leap seconds or leap years. It is a clock that ticks like a metronome, and it has only a local meaning in the context of media synchronization between devices. This is a different notion for a timestamp than what is commonly used across MPEG. This document uses the definition from ETSI TS 103 286 02 to maintain consistency with that specification.

[SOURCE: ETSI TS 103 286 02:2017, 3.1, modified — Note 2 to entry has been added]

3.28

wall clock synchronization

achieving a shared agreement on the progress of time of a wall clock (3.27)

Note 1 to entry: This is a process that takes place between devices.

[SOURCE: ETSI TS 103 286 02:2017, 3.1]