All official LV2 specifications.

Specification API Description Version Status
AtomatomA generic value container and several data types.2.0Stable
Buf Sizebuf-sizeAccess to, and restrictions on, buffer sizes.1.3
Data Accessdata-accessProvides access to LV2_Descriptor::extension_data().1.6Stable
Dynamic ManifestdynmanifestSupport for dynamic data generation.1.6Stable
EventeventA port-based real-time generic event interface.1.12Deprecated
Instance Accessinstance-accessProvides access to the LV2_Handle of a plugin.1.6Stable
LoglogA feature for writing log messages.2.3
LV2lv2coreAn audio plugin interface specification.13.1
MIDImidiA normalised definition of raw MIDI.1.8Stable
MorphmorphPorts that can dynamically change type.1.0Stable
OptionsoptionsInstantiation time options.1.2Stable
ParametersparametersCommon parameters for audio processing.1.4Stable
PatchpatchMessages for accessing and manipulating properties.2.4Stable
Port Groupsport-groupsMulti-channel groups of LV2 ports.1.2Stable
Port Propertiesport-propsVarious port properties.1.2Stable
PresetspresetsPresets for LV2 plugins.2.8Stable
Resize Portresize-portDynamically sized LV2 port buffers.1.0Stable
StatestateAn interface for LV2 plugins to save and restore state.2.1
TimetimeProperties for describing time.1.3
UIuiLV2 plugin UIs of any type.2.19
UnitsunitsUnits for LV2 values.5.10Stable
URI Mapuri-mapA feature for mapping URIs to integers.1.6Deprecated
URIDuridFeatures for mapping URIs to and from integers.1.6Stable
WorkerworkerSupport for a non-realtime plugin worker method.1.1


Version 1.12.0 (2015-04-07)
  • Improve API documentation.
  • Fix merging of version histories in specification documentation.
  • eg-sampler: Add gain parameter.
  • eg-sampler: Support patch:Get, and request initial state from UI.
  • Simplify property restrictions by removing redundancy.
  • lv2core: Add lv2:isSideChain port property.
  • lv2core: Add extern C and visibility attribute to LV2_SYMBOL_EXPORT.
  • lv2core: Relax domain of lv2:minimum lv2:maximum and lv2:default so they can be used to describe properties/parameters as well.
  • parameters: Add range to parameters so hosts know how to control them.
  • patch: Add patch:Copy method.
  • patch: Define patch:Get with no subject to implicitly apply to reciever. This can be used by UIs to get an initial description of a plugin.
  • units: Fix non-existent port type in examples.
  • units: Add lv2:Parameter to domain of units:unit.
Version 1.10.0 (2014-08-08)
  • Fix -Wconversion warnings in headers.
  • lv2specgen: Display deprecated warning on classes marked owl:deprecated.
  • Upgrade to waf 1.7.16.
  • lv2core: Clarify lv2_descriptor() and lv2_lib_descriptor() documentation.
  • atom: Add lv2_atom_sequence_clear() and lv2_atom_sequence_append_event() helper functions.
  • atom: Add lv2_atom_forge_key() for terser object writing.
  • atom: Deprecate Blank and Resource in favour of just Object.
  • atom: Add lv2_atom_forge_is_object_type() and lv2_atom_forge_is_blank() to ease backwards compatibility.
  • event: Minor documentation improvements.
  • patch: Add patch:sequenceNumber for associating replies with requests.
  • ui: Add show interface so UIs can gracefully degrade to separate windows if hosts can not use their widget directly.
  • ui: Fix identifier typos in documentation.
Version 1.8.0 (2014-01-04)
  • Install lv2specgen for use by other projects.
  • lv2specgen: Fix links to externally defined terms.
  • Add scope example plugin from Robin Gareus.
  • lv2core: Add lv2:prototype for property inheritance.
  • atom: Make lv2_atom_*_is_end() arguments const.
  • log: Add missing include string.h to logger.h for memset.
  • ui: Fix LV2_UI_INVALID_PORT_INDEX identifier in documentation.
Version 1.6.0 (2013-08-09)
  • Upgrade to waf 1.7.11.
  • Fix port indices of metronome example.
  • Fix lv2specgen usage from command line.
  • atom: Fix crash in forge.h when pushing atoms to a full buffer.
  • ui: Add ui:updateRate property.
  • ui: Add idle interface so native UIs and foreign toolkits can drive their event loops.
Version 1.4.0 (2013-02-17)
  • Generate book-style HTML documentation from example plugins.
  • Add metronome example plugin to demonstrate sample accurate tempo sync.
  • lv2core: Add lv2:EnvelopePlugin class.
  • lv2core: Set range of lv2:designation to lv2:Designation.
  • lv2core: Make lv2:Parameter rdfs:subClassOf rdf:Property.
  • lv2core: Add lv2:control for designating primary event-based control ports.
  • lv2core: Reserve minor version 0 for unstable development plugins.
  • atom: Improve atom documentation.
  • atom: Fix lv2_atom_sequence_end().
  • atom: Remove atom:stringType in favour of owl:onDatatype so generic tools can understand and validate atom literals.
  • buf-size: Fix typo in bufsz:sequenceSize label.
  • event: Fix incorrect return type in lv2_event_get().
  • log: Add logger convenience API.
  • options: Set the range of opts:requiredOption and opts:supportedOption to opts:Option.
  • patch: Make patch:Set a compact message for setting one property.
  • patch: Add patch:readable and patch:writable for describing available properties.
  • state: Add state:loadDefaultState feature so plugins can have their default state loaded without hard-coding default state as a special case.
  • ui: Fix incorrect linker flag in ui:makeSONameResident documentation.
Version 1.2.0 (2012-10-14)
  • Move all project metadata for extensions (e.g. change log) to separate files to spare hosts from loading them during discovery.
  • Use stricter datatype definitions conformant with the XSD and OWL specifications for better validation.
  • lv2core: Use consistent label style.
  • atom: Fix outdated documentation in forge.h.
  • atom: Fix lv2_atom_object_next() on 32-bit platforms.
  • atom: Add lv2_atom_object_body_get().
  • atom: Use consistent label style.
  • atom: Fix implicit conversions in forge.h that are invalid in C++11.
  • buf-size: Initial release.
  • dynmanifest: Use consistent label style.
  • event: Use consistent label style.
  • event: Remove asserts from event-helper.h.
  • event: Use more precise domain and range for EventPort properties.
  • event: Make event iterator gracefully handle optional ports.
  • midi: Fix definition of SystemExclusive status byte.
  • midi: Add midi:binding and midi:channel predicates.
  • midi: Add C definitions for message types and standard controllers.
  • midi: Add midi:HexByte datatype for status bytes and masks.
  • midi: Use consistent label style.
  • midi: Remove non-standard midi:Tick message type.
  • morph: Initial release.
  • options: Initial release.
  • parameters: Use consistent label style.
  • parameters: Add param:sampleRate.
  • parameters: Add parameters.h of URI defines for convenience.
  • port-groups: Use consistent label style.
  • port-props: Use consistent label style.
  • presets: Add preset banks.
  • presets: Use consistent label style.
  • state: Use consistent label style.
  • time: Use consistent label style.
  • urid: Fix typo in urid:unmap documentation.
  • ui: Add types for WindowsUI, CocoaUI, and Gtk3UI.
  • ui: Use consistent label style.
  • ui: Add missing LV2_SYMBOL_EXPORT declaration for lv2ui_descriptor prototype.
  • units: Remove units:name in favour of rdfs:label.
  • units: Use consistent label style.
Version 1.0.0 (2012-04-16)
  • Initial release as a unified project. Projects can now simply depend on the pkg-config package 'lv2' for all official LV2 APIs.
  • New extensions: atom, log, parameters, patch, port-groups, port-props, resize-port, state, time, worker.
  • lv2core: Merge with unified LV2 package.
  • lv2core: Add new discovery API which allows libraries to read bundle files during discovery, makes library construction/destruction explicit, and adds extensibility to prevent future breakage.
  • lv2core: Relax the range of lv2:index so it can be used for things other than ports.
  • lv2core: Remove lv2:Resource, which turned out to be meaningless.
  • lv2core: Add metadata concept of a designation, a channel or parameter description which can be assigned to ports for more intelligent use by hosts.
  • lv2core: Fix LV2_SYMBOL_EXPORT and lv2_descriptor prototype for Windows.
  • lv2core: Add lv2:CVPort.
  • atom: Initial release.
  • data-access: Merge with unified LV2 package.
  • dynmanifest: Merge with unified LV2 package.
  • event: Merge with unified LV2 package.
  • event: Fix bug in lv2_event_reserve().
  • event: Fix incorrect ranges of some properties.
  • instance-access: Merge with unified LV2 package.
  • log: Initial release.
  • midi: Add class definitions for various message types.
  • midi: Merge with unified LV2 package.
  • midi: Document how to serialise a MidiEvent to a string.
  • parameters: Initial release.
  • patch: Initial release.
  • port-groups: Initial release.
  • port-props: Initial release.
  • presets: Merge with unified LV2 package.
  • presets: Add pset:preset property for describing the preset currently applied to a plugin instance.
  • presets: Remove pset:appliesTo property, use lv2:appliesTo instead.
  • resize-port: Initial release.
  • state: Initial release.
  • time: Initial release.
  • uri-map: Merge with unified LV2 package.
  • urid: Add feature struct names.
  • urid: Merge with unified LV2 package.
  • worker: Initial release.
  • ui: Merge with unified LV2 package.
  • ui: Add ui:parent and ui:resize.
  • ui: Add port protocols and a dynamic notification subscription mechanism, for more flexible communication, and audio port metering without control port kludges.
  • ui: Add support for referring to ports by symbol.
  • ui: Add touch feature to notify the host that the user has grabbed a control.
  • ui: Add ui:portMap for accessing ports by symbol, allowing for UIs to be distributed separately from plugins.
  • units: Add unit for audio frames.
  • units: Add header of URI defines.
  • units: Merge with unified LV2 package.