port-groups
type: Project
license: isc
name: LV2 Port Groups
shortdesc: Multi-channel groups of LV2 ports.
created: 2008-00-00
developer: larsl
developer: me
release:
  revision: 1.4
  created: 2020-04-26
  file-release: lv2-1.18.0.tar.bz2
  blame: me
  changeset:
    item: Replace broken links with detailed Ambisonic channel descriptions.
    item: Remove incorrect type of pg:letterCode.
release:
  revision: 1.2
  created: 2012-10-14
  file-release: lv2-1.2.0.tar.bz2
  blame: me
  changeset:
    item: Use consistent label style.
release:
  revision: 1.0
  created: 2012-04-17
  file-release: lv2-1.0.0.tar.bz2
  blame: me
  changeset:
    item: Initial release.

Group
documentation: 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 pg:StereoGroup with the symbol "input" and use it in many plugins.

sideChainOf
documentation: 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.

subGroupOf
documentation: 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.

source
documentation: 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.

mainInput
documentation: 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 pg:mainInput property.

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

group
documentation: 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.

DiscreteGroup
documentation: 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.

AmbisonicGroup
documentation: 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.