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@prefix bufsz: <http://lv2plug.in/ns/ext/buf-size#> .
@prefix dcs: <http://ontologi.es/doap-changeset#> .
@prefix doap: <http://usefulinc.com/ns/doap#> .
@prefix foaf: <http://xmlns.com/foaf/0.1/> .
@prefix lv2: <http://lv2plug.in/ns/lv2core#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .

<http://lv2plug.in/ns/ext/buf-size>
	a doap:Project ;
	doap:name "LV2 Buf Size" ;
	doap:shortdesc "Access to, and restrictions on, buffer sizes." ;
	doap:created "2012-08-07" ;
	doap:developer <http://drobilla.net/drobilla#me> ;
	doap:release [
		doap:revision "1.4" ;
		doap:created "2015-09-18" ;
		doap:file-release <http://lv2plug.in/spec/lv2-1.14.0.tar.bz2> ;
		dcs:blame <http://drobilla.net/drobilla#me> ;
		dcs:changeset [
			dcs:item [
				rdfs:label "Add bufsz:nominalBlockLength option."
			] , [
				rdfs:label "Add bufsz:coarseBlockLength feature."
			]
		]
	] , [
		doap:revision "1.2" ;
		doap:created "2012-12-21" ;
		doap:file-release <http://lv2plug.in/spec/lv2-1.4.0.tar.bz2> ;
		dcs:blame <http://drobilla.net/drobilla#me> ;
		dcs:changeset [
			dcs:item [
				rdfs:label "Fix typo in bufsz:sequenceSize label."
			]
		]
	] , [
		doap:revision "1.0" ;
		doap:created "2012-10-14" ;
		doap:file-release <http://lv2plug.in/spec/lv2-1.2.0.tar.bz2> ;
		dcs:blame <http://drobilla.net/drobilla#me> ;
		dcs:changeset [
			dcs:item [
				rdfs:label "Initial release."
			]
		]
	] ;
	lv2:documentation """

This extension defines a facility for plugins to get information about the
block length (the sample_count parameter of LV2_Descriptor::run) and port
buffer sizes, as well as several features which can be used to restrict the
block length.

This extension defines features and properties but has no special purpose
API of its own.  The host provides all the relevant information to the plugin
as [options](options.html).

To require restrictions on the block length, plugins can require additional
features: bufsz:boundedBlockLength, bufsz:powerOf2BlockLength, and
bufsz:fixedBlockLength.  These features are data-only, that is they merely
indicate a restriction and do not carry any data or API.

"""^^lv2:Markdown .

bufsz:boundedBlockLength
	lv2:documentation """

A feature that indicates the host will provide both the bufsz:minBlockLength
and bufsz:maxBlockLength options to the plugin.  Plugins that copy data from
audio inputs can require this feature to ensure they know how much space is
required for auxiliary buffers.  Note the minimum may be zero, this feature is
mainly useful to ensure a maximum is available.

All hosts SHOULD support this feature, since it is simple to support and
necessary for any plugins that may need to copy the input.

"""^^lv2:Markdown .

bufsz:fixedBlockLength
	lv2:documentation """

A feature that indicates the host will always call LV2_Descriptor::run() with
the same value for sample_count.  This length MUST be provided as the value of
both the bufsz:minBlockLength and bufsz:maxBlockLength options.

Note that requiring this feature may severely limit the number of hosts capable
of running the plugin.

"""^^lv2:Markdown .

bufsz:powerOf2BlockLength
	lv2:documentation """

A feature that indicates the host will always call LV2_Descriptor::run() with a
power of two sample_count.  Note that this feature does not guarantee the value
is the same each call, to guarantee a fixed power of two block length plugins
must require both this feature and bufsz:fixedBlockLength.

Note that requiring this feature may severely limit the number of hosts capable
of running the plugin.

"""^^lv2:Markdown .

bufsz:coarseBlockLength
	lv2:documentation """

A feature that indicates the plugin prefers coarse, regular block lengths.  For
example, plugins that do not implement sample-accurate control use this feature
to indicate that the host should not split the run cycle because controls have
changed.

Note that this feature is merely a hint, and does not guarantee a fixed block
length.  The run cycle may be split for other reasons, and the blocksize itself
may change anytime.

"""^^lv2:Markdown .

bufsz:maxBlockLength
	lv2:documentation """

The maximum block length the host will ever request the plugin to process at
once, that is, the maximum `sample_count` parameter that will ever be passed to
LV2_Descriptor::run().

"""^^lv2:Markdown .

bufsz:minBlockLength
	lv2:documentation """

The minimum block length the host will ever request the plugin to process at
once, that is, the minimum `sample_count` parameter that will ever be passed to
LV2_Descriptor::run().

"""^^lv2:Markdown .

bufsz:nominalBlockLength
	lv2:documentation """

The typical block length the host will request the plugin to process at once,
that is, the typical `sample_count` parameter that will be passed to
LV2_Descriptor::run().  This will usually be equivalent, or close to, the
maximum block length, but there are no strong guarantees about this value
whatsoever.  Plugins may use this length for optimization purposes, but MUST
NOT assume the host will always process blocks of this length.  In particular,
the host MAY process longer blocks.

"""^^lv2:Markdown .

bufsz:sequenceSize
	lv2:documentation """

This should be provided as an option by hosts that support event ports
(including but not limited to MIDI), so plugins have the ability to allocate
auxiliary buffers large enough to copy the input.

"""^^lv2:Markdown .