For the purposes of the present document, the terms given in
TR 21.905 and the following apply. A term defined in the present document takes precedence over the definition of the same term, if any, in
TR 21.905.
Anchor:
a virtual element for which its position, orientation, scale and other properties are expressed in the trackable space defined by the trackable. A virtual asset's position, orientation, scale and other properties are expressed in relation to an anchor.
Media Session Handler:
a set of functions responsible for handling all 5G control plane operations, such as requesting network assistance, discovering and allocating edge resources, etc.
Presentation Engine:
a set of composite renderers, rendering the component of the scenes.
Reference Points:
geometric points whose position is identified both mathematically and physically.
Trackable:
a real-world object that can be tracked by the XR runtime. Each trackable provides a local reference space, also known as a trackable space, in which an anchor can be expressed.
Swapchain:
a queue of images shared between the XR Application and the XR Runtime
Swapchain image:
image in a swapchain.
XR Application:
application running on an XR Device which offers an XR experience based on an XR Runtime.
XR Device:
a device capable of offering an XR experience.
XR Runtime:
Set of functions provided by the XR Device to the XR Application to create XR experiences.
XR Runtime API:
the API to communicate with an XR Runtime.
XR Scene Manager:
a set of functions that supports the application in arranging the logical and spatial representations.
XR Session:
an application's intention to present XR content to the user.
XR Source Management:
management of data sources provided through the XR runtime.
XR System:
a collection of resources and capabilities from the XR Runtime exposed to the XR Application for the duration of the XR Session.
XR View:
a rendered view of the scene generated by the XR Application and passed on to the XR Runtime during a running XR SessionXR Space: a frame of reference in which 3D coordinates are expressed.
Warping:
correcting the rendered image based on the latest head pose estimation
For the purposes of the present document, the abbreviations given in
TR 21.905 and the following apply. An abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in
TR 21.905.
API
Application Programming Interface
AR
Augmented Reality
AAC
Advanced Audio Coding
AVC
Advanced Video Coding
CPB
Coded Picture Buffer
DPB
Decoded Picture Buffer
ELD
Enhanced Low Delay
EVS
Enhanced Voice Services
glTF
graphics library Transmission Format
GLB
glTF Binary
HEVC
High Efficiency Video Coding
HMD
Head-Mounted Display
HRD
Hypothetical Reference Decoder
HSS
Hypothetical Stream Scheduler
IVAS
Immersive Voice and Audio Services
JSON
JavaScript Object Notation
MPEG
Moving Picture Expert Group
MPEG SD
MPEG Scene Description
MR
Mixed Reality
OP
Observation Point
SLAM
Simultaneous Localisation And Mapping
UE
User Equipment
VCL
Video Coding Layer
VR
Virtual Reality
XR
eXtended Reality