# LV2 Port Groups

Multi-channel groups of LV2 ports.

ID | http://lv2plug.in/ns/ext/port-groups
Version | 1.4
Date | 2020-04-26
Discuss | devel@lists.lv2plug.in (subscribe)

- Index
- History
- API

## Index

Classes | Properties | Instances
--- | --- | ---
Element Group AmbisonicGroup AmbisonicBH1P0Group AmbisonicBH1P1Group AmbisonicBH2P0Group AmbisonicBH2P1Group AmbisonicBH2P2Group AmbisonicBH3P0Group AmbisonicBH3P1Group AmbisonicBH3P2Group AmbisonicBH3P3Group DiscreteGroup FivePointOneGroup FivePointZeroGroup FourPointZeroGroup MidSideGroup MonoGroup SevenPointOneGroup SevenPointOneWideGroup SixPointOneGroup StereoGroup ThreePointZeroGroup InputGroup OutputGroup | element group harmonicDegree harmonicIndex letterCode mainInput mainOutput sideChainOf source subGroupOf | ACN0 ACN1 ACN10 ACN11 ACN12 ACN13 ACN14 ACN15 ACN2 ACN3 ACN4 ACN5 ACN6 ACN7 ACN8 ACN9 center centerLeft centerRight left lowFrequencyEffects rearCenter rearLeft rearRight right side sideLeft sideRight

## Classes

### AmbisonicBH1P0Group

Class

Label | Ambisonic BH1P0
Subclass of | AmbisonicGroup
element |
lv2:designation | ACN0
lv2:index | 0
element |
lv2:designation | ACN1
lv2:index | 1
element |
lv2:designation | ACN3
lv2:index | 2

Ambisonic B stream of horizontal order 1 and peripheral order 0.

### AmbisonicBH1P1Group

Class

Label | Ambisonic BH1P1
Subclass of | AmbisonicGroup
element |
lv2:designation | ACN0
lv2:index | 0
element |
lv2:designation | ACN1
lv2:index | 1
element |
lv2:designation | ACN2
lv2:index | 2
element |
lv2:designation | ACN3
lv2:index | 3

Ambisonic B stream of horizontal order 1 and peripheral order 1.

### AmbisonicBH2P0Group

Class

Label | Ambisonic BH2P0
Subclass of | AmbisonicGroup
element |
lv2:designation | ACN0
lv2:index | 0
element |
lv2:designation | ACN1
lv2:index | 1
element |
lv2:designation | ACN3
lv2:index | 2
element |
lv2:designation | ACN4
lv2:index | 3
element |
lv2:designation | ACN8
lv2:index | 4

Ambisonic B stream of horizontal order 2 and peripheral order 0.

### AmbisonicBH2P1Group

Class

Label | Ambisonic BH2P1
Subclass of | AmbisonicGroup
element |
lv2:designation | ACN0
lv2:index | 0
element |
lv2:designation | ACN1
lv2:index | 1
element |
lv2:designation | ACN2
lv2:index | 2
element |
lv2:designation | ACN3
lv2:index | 3
element |
lv2:designation | ACN4
lv2:index | 4
element |
lv2:designation | ACN8
lv2:index | 5

Ambisonic B stream of horizontal order 2 and peripheral order 1.

### AmbisonicBH2P2Group

Class

Label | Ambisonic BH2P2
Subclass of | AmbisonicGroup
element |
lv2:designation | ACN0
lv2:index | 0
element |
lv2:designation | ACN1
lv2:index | 1
element |
lv2:designation | ACN2
lv2:index | 2
element |
lv2:designation | ACN3
lv2:index | 3
element |
lv2:designation | ACN4
lv2:index | 4
element |
lv2:designation | ACN5
lv2:index | 5
element |
lv2:designation | ACN6
lv2:index | 6
element |
lv2:designation | ACN7
lv2:index | 7
element |
lv2:designation | ACN8
lv2:index | 8

Ambisonic B stream of horizontal order 2 and peripheral order 2.

### AmbisonicBH3P0Group

Class

Label | Ambisonic BH3P0
Subclass of | AmbisonicGroup
element |
lv2:designation | ACN0
lv2:index | 0
element |
lv2:designation | ACN1
lv2:index | 1
element |
lv2:designation | ACN3
lv2:index | 2
element |
lv2:designation | ACN4
lv2:index | 3
element |
lv2:designation | ACN8
lv2:index | 4
element |
lv2:designation | ACN9
lv2:index | 5
element |
lv2:designation | ACN15
lv2:index | 6

Ambisonic B stream of horizontal order 3 and peripheral order 0.

### AmbisonicBH3P1Group

Class

Label | Ambisonic BH3P1
Subclass of | AmbisonicGroup
element |
lv2:designation | ACN0
lv2:index | 0
element |
lv2:designation | ACN1
lv2:index | 1
element |
lv2:designation | ACN2
lv2:index | 2
element |
lv2:designation | ACN3
lv2:index | 3
element |
lv2:designation | ACN4
lv2:index | 4
element |
lv2:designation | ACN8
lv2:index | 5
element |
lv2:designation | ACN9
lv2:index | 6
element |
lv2:designation | ACN15
lv2:index | 7

Ambisonic B stream of horizontal order 3 and peripheral order 1.

### AmbisonicBH3P2Group

Class

Label | Ambisonic BH3P2
Subclass of | AmbisonicGroup
element |
lv2:designation | ACN0
lv2:index | 0
element |
lv2:designation | ACN1
lv2:index | 1
element |
lv2:designation | ACN2
lv2:index | 2
element |
lv2:designation | ACN3
lv2:index | 3
element |
lv2:designation | ACN4
lv2:index | 4
element |
lv2:designation | ACN5
lv2:index | 5
element |
lv2:designation | ACN6
lv2:index | 6
element |
lv2:designation | ACN7
lv2:index | 7
element |
lv2:designation | ACN8
lv2:index | 8
element |
lv2:designation | ACN9
lv2:index | 9
element |
lv2:designation | ACN15
lv2:index | 10

Ambisonic B stream of horizontal order 3 and peripheral order 2.

### AmbisonicBH3P3Group

Class

Label | Ambisonic BH3P3
Subclass of | AmbisonicGroup
element |
lv2:designation | ACN0
lv2:index | 0
element |
lv2:designation | ACN1
lv2:index | 1
element |
lv2:designation | ACN2
lv2:index | 2
element |
lv2:designation | ACN3
lv2:index | 3
element |
lv2:designation | ACN4
lv2:index | 4
element |
lv2:designation | ACN5
lv2:index | 5
element |
lv2:designation | ACN6
lv2:index | 6
element |
lv2:designation | ACN7
lv2:index | 7
element |
lv2:designation | ACN8
lv2:index | 8
element |
lv2:designation | ACN9
lv2:index | 9
element |
lv2:designation | ACN10
lv2:index | 10
element |
lv2:designation | ACN11
lv2:index | 11
element |
lv2:designation | ACN12
lv2:index | 12
element |
lv2:designation | ACN13
lv2:index | 13
element |
lv2:designation | ACN14
lv2:index | 14
element |
lv2:designation | ACN15
lv2:index | 15

Ambisonic B stream of horizontal order 3 and peripheral order 3.

### AmbisonicGroup

Class

Label | Ambisonic Group
Subclass of | Group
Superclass of | AmbisonicBH1P0Group
| AmbisonicBH1P1Group
| AmbisonicBH2P0Group
| AmbisonicBH2P1Group
| AmbisonicBH2P2Group
| AmbisonicBH3P0Group
| AmbisonicBH3P1Group
| AmbisonicBH3P2Group
| AmbisonicBH3P3Group

A group of Ambisonic channels.

These groups are divided into channels which together represent a position in an abstract n-dimensional space. The position of sound in one of these groups does not depend on a particular speaker configuration; a decoder can be used to convert an ambisonic stream for any speaker configuration.

### DiscreteGroup

Class

Label | Discrete Group
Subclass of | Group
Superclass of | FivePointOneGroup
| FivePointZeroGroup
| FourPointZeroGroup
| MidSideGroup
| MonoGroup
| SevenPointOneGroup
| SevenPointOneWideGroup
| SixPointOneGroup
| StereoGroup
| ThreePointZeroGroup

A group of discrete channels.

These groups are divided into channels where each represents a particular speaker location. The position of sound in one of these groups depends on a particular speaker configuration.

### Element

Class

Label | Element
In range of | element

An element of a group, with a designation and optional index.

Restriction on lv2:designation
  owl:cardinality 1
  An element MUST have exactly one lv2:designation.

### FivePointOneGroup

Class

Label | 5.1 Surround
Subclass of | DiscreteGroup
element |
lv2:designation | left
lv2:index | 0
element |
lv2:designation | center
lv2:index | 1
element |
lv2:designation | right
lv2:index | 2
element |
lv2:designation | rearLeft
lv2:index | 3
element |
lv2:designation | rearRight
lv2:index | 4
element |
lv2:designation | lowFrequencyEffects
lv2:index | 5

A 5.1 (3-2 stereo with sub) discrete surround sound group.

### FivePointZeroGroup

Class

Label | 5.0 Surround
Subclass of | DiscreteGroup
element |
lv2:designation | left
lv2:index | 0
element |
lv2:designation | center
lv2:index | 1
element |
lv2:designation | right
lv2:index | 2
element |
lv2:designation | rearLeft
lv2:index | 3
element |
lv2:designation | rearRight
lv2:index | 4

A 5.0 (3-2 stereo) discrete surround sound group.

### FourPointZeroGroup

Class

Label | 4.0 Surround
Subclass of | DiscreteGroup
element |
lv2:designation | left
lv2:index | 0
element |
lv2:designation | center
lv2:index | 1
element |
lv2:designation | right
lv2:index | 2
element |
lv2:designation | rearCenter
lv2:index | 3

A 4.0 (Quadraphonic) discrete surround sound group.

### Group

Class

Label | Port Group
Superclass of | AmbisonicGroup
| DiscreteGroup
| InputGroup
| OutputGroup
In domain of | subGroupOf
In range of | group
| subGroupOf

A set of ports that are logicaly grouped together.

A group logically combines ports which should be considered part of the same stream. For example, two audio ports in a group may form a stereo stream.

Like ports, groups have a lv2:symbol that is unique within the context of the plugin, where group symbols and port symbols reside in the same namespace. In other words, a group on a plugin MUST NOT have the same symbol as any other group or port on that plugin. This makes it possible to uniquely reference a port or group on a plugin with a single identifier and no context.

Group definitions may be shared across plugins for brevity. For example, a plugin collection may define a single URI for a StereoGroup with the symbol "input" and use it in many plugins.

Restriction on lv2:symbol
  owl:cardinality 1
  A Group MUST have exactly one string lv2:symbol.

### InputGroup

Class

Label | Input Group
Subclass of | Group
In range of | mainInput
| source

A group which contains exclusively inputs.

### MidSideGroup

Class

Label | Mid-Side Stereo
Subclass of | DiscreteGroup
element |
lv2:designation | center
lv2:index | 0
element |
lv2:designation | side
lv2:index | 1

A 2-channel mid-side stereo audio group.

### MonoGroup

Class

Label | Mono
Subclass of | DiscreteGroup
element |
lv2:designation | center
lv2:index | 0

A single channel audio group.

### OutputGroup

Class

Label | Output Group
Subclass of | Group
In domain of | source
In range of | mainOutput

A group which contains exclusively outputs.

### SevenPointOneGroup

Class

Label | 7.1 Surround
Subclass of | DiscreteGroup
element |
lv2:designation | left
lv2:index | 0
element |
lv2:designation | center
lv2:index | 1
element |
lv2:designation | right
lv2:index | 2
element |
lv2:designation | sideLeft
lv2:index | 3
element |
lv2:designation | sideRight
lv2:index | 4
element |
lv2:designation | rearLeft
lv2:index | 5
element |
lv2:designation | rearRight
lv2:index | 6
element |
lv2:designation | lowFrequencyEffects
lv2:index | 7

A 7.1 discrete surround sound group.

### SevenPointOneWideGroup

Class

Label | 7.1 Surround (Wide)
Subclass of | DiscreteGroup
element |
lv2:designation | left
lv2:index | 0
element |
lv2:designation | centerLeft
lv2:index | 1
element |
lv2:designation | center
lv2:index | 2
element |
lv2:designation | centerRight
lv2:index | 3
element |
lv2:designation | right
lv2:index | 4
element |
lv2:designation | rearLeft
lv2:index | 5
element |
lv2:designation | rearRight
lv2:index | 6
element |
lv2:designation | lowFrequencyEffects
lv2:index | 7

A 7.1 wide discrete surround sound group.

### SixPointOneGroup

Class

Label | 6.1 Surround
Subclass of | DiscreteGroup
element |
lv2:designation | left
lv2:index | 0
element |
lv2:designation | center
lv2:index | 1
element |
lv2:designation | right
lv2:index | 2
element |
lv2:designation | sideLeft
lv2:index | 3
element |
lv2:designation | sideRight
lv2:index | 4
element |
lv2:designation | rearCenter
lv2:index | 5
element |
lv2:designation | lowFrequencyEffects
lv2:index | 6

A 6.1 discrete surround sound group.

### StereoGroup

Class

Label | Stereo
Subclass of | DiscreteGroup
element |
lv2:designation | left
lv2:index | 0
element |
lv2:designation | right
lv2:index | 1

A 2-channel discrete stereo audio group.

### ThreePointZeroGroup

Class

Label | 3.0 Surround
Subclass of | DiscreteGroup
element |
lv2:designation | left
lv2:index | 0
element |
lv2:designation | right
lv2:index | 1
element |
lv2:designation | rearCenter
lv2:index | 2

A 3.0 discrete surround sound group.

## Properties

### element

Property

Label | element
Range | Element
Type | Object Property

An element within a port group.

### group

Property

Label | group
Domain | lv2:Port
Range | Group
Type | Object Property

Group that this port is a part of.

Indicates that this port is a part of a group of ports on the plugin. The port should also have an lv2:designation property to define its designation within that group.

### harmonicDegree

Property

Label | harmonic degree
Domain | lv2:Channel
Range | xsd:integer
Type | Datatype Property

The degree coefficient (l) of the spherical harmonic for an Ambisonic channel.

### harmonicIndex

Property

Label | harmonic index
Domain | lv2:Channel
Range | xsd:integer
Type | Datatype Property

The index coefficient (m) of the spherical harmonic for an Ambisonic channel.

### letterCode

Property

Label | ambisonic letter code
Domain | lv2:Channel
Range | rdf:PlainLiteral
Type | Datatype Property

The YuMa letter code for an Ambisonic channel.

### mainInput

Property

Label | main input
Domain | lv2:Plugin
Range | InputGroup
Type | Object Property

Input group that is the primary input of the plugin.

Indicates that this group should be considered the "main" input, i.e. the primary task is processing the signal in this group. A plugin MUST NOT have more than one mainInput property.

### mainOutput

Property

Label | main output
Domain | lv2:Plugin
Range | OutputGroup
Type | Object Property

Output group that is the primary output of the plugin.

Indicates that this group should be considered the "main" output. The main output group SHOULD have the main input group as a source.

### sideChainOf

Property

Label | side-chain of
Type | Object Property

Port or grou is a side chain of another.

Indicates that this port or group should be considered a "side chain" of some other port or group. The precise definition of "side chain" depends on the plugin, but in general this group should be considered a modifier to some other group, rather than an independent input itself.

### source

Property

Label | source
Domain | OutputGroup
Range | InputGroup
Type | Object Property

Port or group that this group is the output of.

Indicates that this port or group should be considered the "result" of some other port or group. This property only makes sense on groups with outputs when the source is a group with inputs. This can be used to convey a relationship between corresponding input and output groups with different types, for example in a mono to stereo plugin.

### subGroupOf

Property

Label | sub-group of
Domain | Group
Range | Group
Type | Object Property

Group is a child of another group.

Indicates that this group is a child of another group. This property has no meaning with respect to plugin execution, but the host may find this information useful to provide a better user interface. Note that being a sub-group does not relax the restriction that the group MUST have a unique symbol with respect to the plugin.

## Instances

### ACN0

Instance

Label | ACN0
Type | lv2:Channel
harmonicDegree | 0
harmonicIndex | 0
letterCode | W

Ambisonic channel 0 (W): degree 0, index 0.

### ACN1

Instance

Label | ACN1
Type | lv2:Channel
harmonicDegree | 1
harmonicIndex | -1
letterCode | Y

Ambisonic channel 1 (Y): degree 1, index -1.

### ACN10

Instance

Label | ACN10
Type | lv2:Channel
harmonicDegree | 3
harmonicIndex | -2
letterCode | O

Ambisonic channel 10 (O): degree 3, index -2.

### ACN11

Instance

Label | ACN11
Type | lv2:Channel
harmonicDegree | 3
harmonicIndex | -1
letterCode | M

Ambisonic channel 11 (M): degree 3, index -1.

### ACN12

Instance

Label | ACN12
Type | lv2:Channel
harmonicDegree | 3
harmonicIndex | 0
letterCode | K

Ambisonic channel 12 (K): degree 3, index 0.

### ACN13

Instance

Label | ACN13
Type | lv2:Channel
harmonicDegree | 3
harmonicIndex | 1
letterCode | L

Ambisonic channel 13 (L): degree 3, index 1.

### ACN14

Instance

Label | ACN14
Type | lv2:Channel
harmonicDegree | 3
harmonicIndex | 2
letterCode | N

Ambisonic channel 14 (N): degree 3, index 2.

### ACN15

Instance

Label | ACN15
Type | lv2:Channel
harmonicDegree | 3
harmonicIndex | 3
letterCode | P

Ambisonic channel 15 (P): degree 3, index 3.

### ACN2

Instance

Label | ACN2
Type | lv2:Channel
harmonicDegree | 1
harmonicIndex | 0
letterCode | Z

Ambisonic channel 2 (Z): degree 1, index 0.

### ACN3

Instance

Label | ACN3
Type | lv2:Channel
harmonicDegree | 1
harmonicIndex | 1
letterCode | X

Ambisonic channel 3 (X): degree 1, index 1.

### ACN4

Instance

Label | ACN4
Type | lv2:Channel
harmonicDegree | 2
harmonicIndex | -2
letterCode | V

Ambisonic channel 4 (V): degree 2, index -2.

### ACN5

Instance

Label | ACN5
Type | lv2:Channel
harmonicDegree | 2
harmonicIndex | -1
letterCode | T

Ambisonic channel 5 (T): degree 2, index -1.

### ACN6

Instance

Label | ACN6
Type | lv2:Channel
harmonicDegree | 2
harmonicIndex | 0
letterCode | R

Ambisonic channel 6 (R): degree 2, index 0.

### ACN7

Instance

Label | ACN7
Type | lv2:Channel
harmonicDegree | 2
harmonicIndex | 1
letterCode | S

Ambisonic channel 7 (S): degree 2, index 1.

### ACN8

Instance

Label | ACN8
Type | lv2:Channel
harmonicDegree | 2
harmonicIndex | 2
letterCode | U

Ambisonic channel 8 (U): degree 2, index 2.

### ACN9

Instance

Label | ACN9
Type | lv2:Channel
harmonicDegree | 3
harmonicIndex | -3
letterCode | Q

Ambisonic channel 9 (Q): degree 3, index -3.

### center

Instance

Label | center
Type | lv2:Channel

The center channel of a discrete audio group.

### centerLeft

Instance

Label | center left
Type | lv2:Channel

The center-left channel of a 7.1 wide surround sound group.

### centerRight

Instance

Label | center right
Type | lv2:Channel

The center-right channel of a 7.1 wide surround sound group.

### left

Instance

Label | left
Type | lv2:Channel

The left channel of a stereo audio group.

### lowFrequencyEffects

Instance

Label | low-frequency effects
Type | lv2:Channel

The LFE channel of a *.1 surround sound group.

### rearCenter

Instance

Label | rear center
Type | lv2:Channel

The rear-center channel of a surround sound group.

### rearLeft

Instance

Label | rear left
Type | lv2:Channel

The rear-left channel of a surround sound group.

### rearRight

Instance

Label | rear right
Type | lv2:Channel

The rear-right channel of a surround sound group.

### right

Instance

Label | right
Type | lv2:Channel

The right channel of a stereo audio group.

### side

Instance

Label | side
Type | lv2:Channel

The side channel of a mid-side audio group.

### sideLeft

Instance

Label | side left
Type | lv2:Channel

The side-left channel of a 6.1 or 7.1 surround sound group.

### sideRight

Instance

Label | side right
Type | lv2:Channel

The side-right channel of a 6.1 or 7.1 surround sound group.

## History

Version 1.4 (2020-04-26)
  - Replace broken links with detailed Ambisonic channel descriptions.
  - Remove incorrect type of pg:letterCode.
Version 1.2 (2012-10-14)
  - Use consistent label style.
Version 1.0 (2012-04-17)
  - Initial release.