changeset 0:7632b9bf0cff

Initial stub plugin commit
author Chris Cannam
date Thu, 17 Jul 2014 12:16:02 +0100
parents
children f21753c504e1
files .hgignore Makefile flattendynamics-ladspa.cpp flattendynamics-ladspa.h ladspa.h
diffstat 5 files changed, 821 insertions(+), 0 deletions(-) [+]
line wrap: on
line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/.hgignore	Thu Jul 17 12:16:02 2014 +0100
@@ -0,0 +1,4 @@
+syntax: glob
+*~
+*.o
+*.so
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Makefile	Thu Jul 17 12:16:02 2014 +0100
@@ -0,0 +1,16 @@
+
+CXXFLAGS	:= -DLADSPA -fpic -O3 -ffast-math -msse -msse2 -mfpmath=sse -ftree-vectorize
+
+SOURCES		:= flattendynamics-ladspa.cpp 
+OBJECTS		:= flattendynamics-ladspa.o 
+HEADERS		:= flattendynamics-ladspa.h ladspa.h
+
+flattendynamics.so:	$(OBJECTS)
+	$(CXX) $^ $(CXXFLAGS) -shared -o $@
+
+clean:		
+	rm -f $(OBJECTS)
+
+flattendynamics.o:	$(HEADERS)
+flattendynamics-ladspa.o:	$(HEADERS)
+
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/flattendynamics-ladspa.cpp	Thu Jul 17 12:16:02 2014 +0100
@@ -0,0 +1,153 @@
+/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
+
+#include "flattendynamics-ladspa.h"
+
+#include <alloca.h>
+#include <iostream>
+#include <cmath>
+
+const char *const
+FlattenDynamics::portNames[PortCount] =
+{
+    "Input",
+    "Output",
+};
+
+const LADSPA_PortDescriptor 
+FlattenDynamics::ports[PortCount] =
+{
+    LADSPA_PORT_INPUT  | LADSPA_PORT_AUDIO,
+    LADSPA_PORT_OUTPUT | LADSPA_PORT_AUDIO,
+};
+
+const LADSPA_PortRangeHint 
+FlattenDynamics::hints[PortCount] =
+{
+    { 0, 0, 0 },
+    { 0, 0, 0 },
+};
+
+const LADSPA_Properties
+FlattenDynamics::properties = LADSPA_PROPERTY_HARD_RT_CAPABLE;
+
+const LADSPA_Descriptor 
+FlattenDynamics::ladspaDescriptor =
+{
+    0xf0b375, // "Unique" ID
+    "flattendynamics", // Label
+    properties,
+    "FlattenDynamics", // Name
+    "Queen Mary, University of London", // Maker
+    "BSD", // Copyright
+    PortCount,
+    ports,
+    portNames,
+    hints,
+    0, // Implementation data
+    instantiate,
+    connectPort,
+    activate,
+    run,
+    0, // Run adding
+    0, // Set run adding gain
+    deactivate,
+    cleanup
+};
+
+const LADSPA_Descriptor *
+FlattenDynamics::getDescriptor(unsigned long index)
+{
+    if (index == 0) return &ladspaDescriptor;
+    return 0;
+}
+
+FlattenDynamics::FlattenDynamics(int sampleRate) :
+    m_sampleRate(sampleRate),
+    m_input(0),
+    m_output(0)
+{
+    reset();
+}
+
+FlattenDynamics::~FlattenDynamics()
+{
+}
+    
+LADSPA_Handle
+FlattenDynamics::instantiate(const LADSPA_Descriptor *, unsigned long rate)
+{
+    FlattenDynamics *flatten = new FlattenDynamics(rate);
+    return flatten;
+}
+
+void
+FlattenDynamics::connectPort(LADSPA_Handle handle,
+                           unsigned long port, LADSPA_Data *location)
+{
+    FlattenDynamics *flatten = (FlattenDynamics *)handle;
+
+    float **ports[PortCount] = {
+	&flatten->m_input,
+	&flatten->m_output,
+    };
+
+    *ports[port] = (float *)location;
+}
+
+void
+FlattenDynamics::activate(LADSPA_Handle handle)
+{
+    FlattenDynamics *flatten = (FlattenDynamics *)handle;
+    flatten->reset();
+}
+
+void
+FlattenDynamics::run(LADSPA_Handle handle, unsigned long samples)
+{
+    FlattenDynamics *flatten = (FlattenDynamics *)handle;
+    flatten->runImpl(samples);
+}
+
+void
+FlattenDynamics::deactivate(LADSPA_Handle handle)
+{
+    activate(handle); // both functions just reset the plugin
+}
+
+void
+FlattenDynamics::cleanup(LADSPA_Handle handle)
+{
+    delete (FlattenDynamics *)handle;
+}
+
+void
+FlattenDynamics::reset()
+{
+}
+
+void
+FlattenDynamics::updateParameters()
+{
+}
+
+void
+FlattenDynamics::runImpl(unsigned long sampleCount)
+{
+    if (!m_input || !m_output) return;
+    updateParameters();
+
+    int ii = 0;
+    int oi = 0;
+    const int sc = sampleCount;
+
+    while (ii < sc) {
+        //!!!
+    }
+}
+
+const LADSPA_Descriptor *
+ladspa_descriptor(unsigned long ix)
+{
+    return FlattenDynamics::getDescriptor(ix);
+}
+
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/flattendynamics-ladspa.h	Thu Jul 17 12:16:02 2014 +0100
@@ -0,0 +1,45 @@
+/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
+
+#ifndef FLATTENDYNAMICS_LADSPA_H
+#define FLATTENDYNAMICS_LADSPA_H
+
+#include <ladspa.h>
+
+class FlattenDynamics
+{
+public:
+    static const LADSPA_Descriptor *getDescriptor(unsigned long index);
+
+private:
+    FlattenDynamics(int sampleRate);
+    ~FlattenDynamics();
+
+    enum {
+        InputPort     = 0,
+	OutputPort    = 1,
+	PortCount     = 2,
+    };
+
+    static const char *const portNames[PortCount];
+    static const LADSPA_PortDescriptor ports[PortCount];
+    static const LADSPA_PortRangeHint hints[PortCount];
+    static const LADSPA_Properties properties;
+    static const LADSPA_Descriptor ladspaDescriptor;
+
+    static LADSPA_Handle instantiate(const LADSPA_Descriptor *, unsigned long);
+    static void connectPort(LADSPA_Handle, unsigned long, LADSPA_Data *);
+    static void activate(LADSPA_Handle);
+    static void run(LADSPA_Handle, unsigned long);
+    static void deactivate(LADSPA_Handle);
+    static void cleanup(LADSPA_Handle);
+
+    void reset();
+    void runImpl(unsigned long);
+    void updateParameters();
+
+    int m_sampleRate;
+    float *m_input;
+    float *m_output;
+};
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ladspa.h	Thu Jul 17 12:16:02 2014 +0100
@@ -0,0 +1,603 @@
+/* ladspa.h
+
+   Linux Audio Developer's Simple Plugin API Version 1.1[LGPL].
+   Copyright (C) 2000-2002 Richard W.E. Furse, Paul Barton-Davis,
+   Stefan Westerfeld.
+   
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public License
+   as published by the Free Software Foundation; either version 2.1 of
+   the License, or (at your option) any later version.
+   
+   This library is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+   Lesser General Public License for more details.
+   
+   You should have received a copy of the GNU Lesser General Public
+   License along with this library; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+   USA. */
+
+#ifndef LADSPA_INCLUDED
+#define LADSPA_INCLUDED
+
+#define LADSPA_VERSION "1.1"
+#define LADSPA_VERSION_MAJOR 1
+#define LADSPA_VERSION_MINOR 1
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*****************************************************************************/
+
+/* Overview: 
+
+   There is a large number of synthesis packages in use or development
+   on the Linux platform at this time. This API (`The Linux Audio
+   Developer's Simple Plugin API') attempts to give programmers the
+   ability to write simple `plugin' audio processors in C/C++ and link
+   them dynamically (`plug') into a range of these packages (`hosts').
+   It should be possible for any host and any plugin to communicate
+   completely through this interface.
+
+   This API is deliberately short and simple. To achieve compatibility
+   with a range of promising Linux sound synthesis packages it
+   attempts to find the `greatest common divisor' in their logical
+   behaviour. Having said this, certain limiting decisions are
+   implicit, notably the use of a fixed type (LADSPA_Data) for all
+   data transfer and absence of a parameterised `initialisation'
+   phase. See below for the LADSPA_Data typedef.
+
+   Plugins are expected to distinguish between control and audio
+   data. Plugins have `ports' that are inputs or outputs for audio or
+   control data and each plugin is `run' for a `block' corresponding
+   to a short time interval measured in samples. Audio data is
+   communicated using arrays of LADSPA_Data, allowing a block of audio
+   to be processed by the plugin in a single pass. Control data is
+   communicated using single LADSPA_Data values. Control data has a
+   single value at the start of a call to the `run()' or `run_adding()'
+   function, and may be considered to remain this value for its
+   duration. The plugin may assume that all its input and output ports
+   have been connected to the relevant data location (see the
+   `connect_port()' function below) before it is asked to run.
+
+   Plugins will reside in shared object files suitable for dynamic
+   linking by dlopen() and family. The file will provide a number of
+   `plugin types' that can be used to instantiate actual plugins
+   (sometimes known as `plugin instances') that can be connected
+   together to perform tasks.
+
+   This API contains very limited error-handling. */
+
+/*****************************************************************************/
+
+/* Fundamental data type passed in and out of plugin. This data type
+   is used to communicate audio samples and control values. It is
+   assumed that the plugin will work sensibly given any numeric input
+   value although it may have a preferred range (see hints below). 
+
+   For audio it is generally assumed that 1.0f is the `0dB' reference
+   amplitude and is a `normal' signal level. */
+
+typedef float LADSPA_Data;
+
+/*****************************************************************************/
+
+/* Special Plugin Properties: 
+ 
+   Optional features of the plugin type are encapsulated in the
+   LADSPA_Properties type. This is assembled by ORing individual
+   properties together. */
+
+typedef int LADSPA_Properties;
+
+/* Property LADSPA_PROPERTY_REALTIME indicates that the plugin has a
+   real-time dependency (e.g. listens to a MIDI device) and so its
+   output must not be cached or subject to significant latency. */
+#define LADSPA_PROPERTY_REALTIME        0x1
+
+/* Property LADSPA_PROPERTY_INPLACE_BROKEN indicates that the plugin
+   may cease to work correctly if the host elects to use the same data
+   location for both input and output (see connect_port()). This
+   should be avoided as enabling this flag makes it impossible for
+   hosts to use the plugin to process audio `in-place.' */
+#define LADSPA_PROPERTY_INPLACE_BROKEN  0x2
+
+/* Property LADSPA_PROPERTY_HARD_RT_CAPABLE indicates that the plugin
+   is capable of running not only in a conventional host but also in a
+   `hard real-time' environment. To qualify for this the plugin must
+   satisfy all of the following:
+
+   (1) The plugin must not use malloc(), free() or other heap memory
+   management within its run() or run_adding() functions. All new
+   memory used in run() must be managed via the stack. These
+   restrictions only apply to the run() function.
+
+   (2) The plugin will not attempt to make use of any library
+   functions with the exceptions of functions in the ANSI standard C
+   and C maths libraries, which the host is expected to provide.
+
+   (3) The plugin will not access files, devices, pipes, sockets, IPC
+   or any other mechanism that might result in process or thread
+   blocking.
+      
+   (4) The plugin will take an amount of time to execute a run() or
+   run_adding() call approximately of form (A+B*SampleCount) where A
+   and B depend on the machine and host in use. This amount of time
+   may not depend on input signals or plugin state. The host is left
+   the responsibility to perform timings to estimate upper bounds for
+   A and B. */
+#define LADSPA_PROPERTY_HARD_RT_CAPABLE 0x4
+
+#define LADSPA_IS_REALTIME(x)        ((x) & LADSPA_PROPERTY_REALTIME)
+#define LADSPA_IS_INPLACE_BROKEN(x)  ((x) & LADSPA_PROPERTY_INPLACE_BROKEN)
+#define LADSPA_IS_HARD_RT_CAPABLE(x) ((x) & LADSPA_PROPERTY_HARD_RT_CAPABLE)
+
+/*****************************************************************************/
+
+/* Plugin Ports: 
+
+   Plugins have `ports' that are inputs or outputs for audio or
+   data. Ports can communicate arrays of LADSPA_Data (for audio
+   inputs/outputs) or single LADSPA_Data values (for control
+   input/outputs). This information is encapsulated in the
+   LADSPA_PortDescriptor type which is assembled by ORing individual
+   properties together.
+
+   Note that a port must be an input or an output port but not both
+   and that a port must be a control or audio port but not both. */
+
+typedef int LADSPA_PortDescriptor;
+
+/* Property LADSPA_PORT_INPUT indicates that the port is an input. */
+#define LADSPA_PORT_INPUT   0x1
+
+/* Property LADSPA_PORT_OUTPUT indicates that the port is an output. */
+#define LADSPA_PORT_OUTPUT  0x2
+
+/* Property LADSPA_PORT_CONTROL indicates that the port is a control
+   port. */
+#define LADSPA_PORT_CONTROL 0x4
+
+/* Property LADSPA_PORT_AUDIO indicates that the port is a audio
+   port. */
+#define LADSPA_PORT_AUDIO   0x8
+
+#define LADSPA_IS_PORT_INPUT(x)   ((x) & LADSPA_PORT_INPUT)
+#define LADSPA_IS_PORT_OUTPUT(x)  ((x) & LADSPA_PORT_OUTPUT)
+#define LADSPA_IS_PORT_CONTROL(x) ((x) & LADSPA_PORT_CONTROL)
+#define LADSPA_IS_PORT_AUDIO(x)   ((x) & LADSPA_PORT_AUDIO)
+
+/*****************************************************************************/
+
+/* Plugin Port Range Hints: 
+
+   The host may wish to provide a representation of data entering or
+   leaving a plugin (e.g. to generate a GUI automatically). To make
+   this more meaningful, the plugin should provide `hints' to the host
+   describing the usual values taken by the data.
+   
+   Note that these are only hints. The host may ignore them and the
+   plugin must not assume that data supplied to it is meaningful. If
+   the plugin receives invalid input data it is expected to continue
+   to run without failure and, where possible, produce a sensible
+   output (e.g. a high-pass filter given a negative cutoff frequency
+   might switch to an all-pass mode).
+    
+   Hints are meaningful for all input and output ports but hints for
+   input control ports are expected to be particularly useful.
+   
+   More hint information is encapsulated in the
+   LADSPA_PortRangeHintDescriptor type which is assembled by ORing
+   individual hint types together. Hints may require further
+   LowerBound and UpperBound information.
+
+   All the hint information for a particular port is aggregated in the
+   LADSPA_PortRangeHint structure. */
+
+typedef int LADSPA_PortRangeHintDescriptor;
+
+/* Hint LADSPA_HINT_BOUNDED_BELOW indicates that the LowerBound field
+   of the LADSPA_PortRangeHint should be considered meaningful. The
+   value in this field should be considered the (inclusive) lower
+   bound of the valid range. If LADSPA_HINT_SAMPLE_RATE is also
+   specified then the value of LowerBound should be multiplied by the
+   sample rate. */
+#define LADSPA_HINT_BOUNDED_BELOW   0x1
+
+/* Hint LADSPA_HINT_BOUNDED_ABOVE indicates that the UpperBound field
+   of the LADSPA_PortRangeHint should be considered meaningful. The
+   value in this field should be considered the (inclusive) upper
+   bound of the valid range. If LADSPA_HINT_SAMPLE_RATE is also
+   specified then the value of UpperBound should be multiplied by the
+   sample rate. */
+#define LADSPA_HINT_BOUNDED_ABOVE   0x2
+
+/* Hint LADSPA_HINT_TOGGLED indicates that the data item should be
+   considered a Boolean toggle. Data less than or equal to zero should
+   be considered `off' or `false,' and data above zero should be
+   considered `on' or `true.' LADSPA_HINT_TOGGLED may not be used in
+   conjunction with any other hint except LADSPA_HINT_DEFAULT_0 or
+   LADSPA_HINT_DEFAULT_1. */
+#define LADSPA_HINT_TOGGLED         0x4
+
+/* Hint LADSPA_HINT_SAMPLE_RATE indicates that any bounds specified
+   should be interpreted as multiples of the sample rate. For
+   instance, a frequency range from 0Hz to the Nyquist frequency (half
+   the sample rate) could be requested by this hint in conjunction
+   with LowerBound = 0 and UpperBound = 0.5. Hosts that support bounds
+   at all must support this hint to retain meaning. */
+#define LADSPA_HINT_SAMPLE_RATE     0x8
+
+/* Hint LADSPA_HINT_LOGARITHMIC indicates that it is likely that the
+   user will find it more intuitive to view values using a logarithmic
+   scale. This is particularly useful for frequencies and gains. */
+#define LADSPA_HINT_LOGARITHMIC     0x10
+
+/* Hint LADSPA_HINT_INTEGER indicates that a user interface would
+   probably wish to provide a stepped control taking only integer
+   values. Any bounds set should be slightly wider than the actual
+   integer range required to avoid floating point rounding errors. For
+   instance, the integer set {0,1,2,3} might be described as [-0.1,
+   3.1]. */
+#define LADSPA_HINT_INTEGER         0x20
+
+/* The various LADSPA_HINT_HAS_DEFAULT_* hints indicate a `normal'
+   value for the port that is sensible as a default. For instance,
+   this value is suitable for use as an initial value in a user
+   interface or as a value the host might assign to a control port
+   when the user has not provided one. Defaults are encoded using a
+   mask so only one default may be specified for a port. Some of the
+   hints make use of lower and upper bounds, in which case the
+   relevant bound or bounds must be available and
+   LADSPA_HINT_SAMPLE_RATE must be applied as usual. The resulting
+   default must be rounded if LADSPA_HINT_INTEGER is present. Default
+   values were introduced in LADSPA v1.1. */
+#define LADSPA_HINT_DEFAULT_MASK    0x3C0
+
+/* This default values indicates that no default is provided. */
+#define LADSPA_HINT_DEFAULT_NONE    0x0
+
+/* This default hint indicates that the suggested lower bound for the
+   port should be used. */
+#define LADSPA_HINT_DEFAULT_MINIMUM 0x40
+
+/* This default hint indicates that a low value between the suggested
+   lower and upper bounds should be chosen. For ports with
+   LADSPA_HINT_LOGARITHMIC, this should be exp(log(lower) * 0.75 +
+   log(upper) * 0.25). Otherwise, this should be (lower * 0.75 + upper
+   * 0.25). */
+#define LADSPA_HINT_DEFAULT_LOW     0x80
+
+/* This default hint indicates that a middle value between the
+   suggested lower and upper bounds should be chosen. For ports with
+   LADSPA_HINT_LOGARITHMIC, this should be exp(log(lower) * 0.5 +
+   log(upper) * 0.5). Otherwise, this should be (lower * 0.5 + upper *
+   0.5). */
+#define LADSPA_HINT_DEFAULT_MIDDLE  0xC0
+
+/* This default hint indicates that a high value between the suggested
+   lower and upper bounds should be chosen. For ports with
+   LADSPA_HINT_LOGARITHMIC, this should be exp(log(lower) * 0.25 +
+   log(upper) * 0.75). Otherwise, this should be (lower * 0.25 + upper
+   * 0.75). */
+#define LADSPA_HINT_DEFAULT_HIGH    0x100
+
+/* This default hint indicates that the suggested upper bound for the
+   port should be used. */
+#define LADSPA_HINT_DEFAULT_MAXIMUM 0x140
+
+/* This default hint indicates that the number 0 should be used. Note
+   that this default may be used in conjunction with
+   LADSPA_HINT_TOGGLED. */
+#define LADSPA_HINT_DEFAULT_0       0x200
+
+/* This default hint indicates that the number 1 should be used. Note
+   that this default may be used in conjunction with
+   LADSPA_HINT_TOGGLED. */
+#define LADSPA_HINT_DEFAULT_1       0x240
+
+/* This default hint indicates that the number 100 should be used. */
+#define LADSPA_HINT_DEFAULT_100     0x280
+
+/* This default hint indicates that the Hz frequency of `concert A'
+   should be used. This will be 440 unless the host uses an unusual
+   tuning convention, in which case it may be within a few Hz. */
+#define LADSPA_HINT_DEFAULT_440     0x2C0
+
+#define LADSPA_IS_HINT_BOUNDED_BELOW(x)   ((x) & LADSPA_HINT_BOUNDED_BELOW)
+#define LADSPA_IS_HINT_BOUNDED_ABOVE(x)   ((x) & LADSPA_HINT_BOUNDED_ABOVE)
+#define LADSPA_IS_HINT_TOGGLED(x)         ((x) & LADSPA_HINT_TOGGLED)
+#define LADSPA_IS_HINT_SAMPLE_RATE(x)     ((x) & LADSPA_HINT_SAMPLE_RATE)
+#define LADSPA_IS_HINT_LOGARITHMIC(x)     ((x) & LADSPA_HINT_LOGARITHMIC)
+#define LADSPA_IS_HINT_INTEGER(x)         ((x) & LADSPA_HINT_INTEGER)
+
+#define LADSPA_IS_HINT_HAS_DEFAULT(x)     ((x) & LADSPA_HINT_DEFAULT_MASK)
+#define LADSPA_IS_HINT_DEFAULT_MINIMUM(x) (((x) & LADSPA_HINT_DEFAULT_MASK)   \
+                                           == LADSPA_HINT_DEFAULT_MINIMUM)
+#define LADSPA_IS_HINT_DEFAULT_LOW(x)     (((x) & LADSPA_HINT_DEFAULT_MASK)   \
+                                           == LADSPA_HINT_DEFAULT_LOW)
+#define LADSPA_IS_HINT_DEFAULT_MIDDLE(x)  (((x) & LADSPA_HINT_DEFAULT_MASK)   \
+                                           == LADSPA_HINT_DEFAULT_MIDDLE)
+#define LADSPA_IS_HINT_DEFAULT_HIGH(x)    (((x) & LADSPA_HINT_DEFAULT_MASK)   \
+                                           == LADSPA_HINT_DEFAULT_HIGH)
+#define LADSPA_IS_HINT_DEFAULT_MAXIMUM(x) (((x) & LADSPA_HINT_DEFAULT_MASK)   \
+                                           == LADSPA_HINT_DEFAULT_MAXIMUM)
+#define LADSPA_IS_HINT_DEFAULT_0(x)       (((x) & LADSPA_HINT_DEFAULT_MASK)   \
+                                           == LADSPA_HINT_DEFAULT_0)
+#define LADSPA_IS_HINT_DEFAULT_1(x)       (((x) & LADSPA_HINT_DEFAULT_MASK)   \
+                                           == LADSPA_HINT_DEFAULT_1)
+#define LADSPA_IS_HINT_DEFAULT_100(x)     (((x) & LADSPA_HINT_DEFAULT_MASK)   \
+                                           == LADSPA_HINT_DEFAULT_100)
+#define LADSPA_IS_HINT_DEFAULT_440(x)     (((x) & LADSPA_HINT_DEFAULT_MASK)   \
+                                            == LADSPA_HINT_DEFAULT_440)
+
+typedef struct _LADSPA_PortRangeHint {
+
+  /* Hints about the port. */
+  LADSPA_PortRangeHintDescriptor HintDescriptor;
+
+  /* Meaningful when hint LADSPA_HINT_BOUNDED_BELOW is active. When
+     LADSPA_HINT_SAMPLE_RATE is also active then this value should be
+     multiplied by the relevant sample rate. */
+  LADSPA_Data LowerBound;
+
+  /* Meaningful when hint LADSPA_HINT_BOUNDED_ABOVE is active. When
+     LADSPA_HINT_SAMPLE_RATE is also active then this value should be
+     multiplied by the relevant sample rate. */
+  LADSPA_Data UpperBound;
+
+} LADSPA_PortRangeHint;
+
+/*****************************************************************************/
+
+/* Plugin Handles: 
+
+   This plugin handle indicates a particular instance of the plugin
+   concerned. It is valid to compare this to NULL (0 for C++) but
+   otherwise the host should not attempt to interpret it. The plugin
+   may use it to reference internal instance data. */
+
+typedef void * LADSPA_Handle;
+
+/*****************************************************************************/
+
+/* Descriptor for a Type of Plugin: 
+
+   This structure is used to describe a plugin type. It provides a
+   number of functions to examine the type, instantiate it, link it to
+   buffers and workspaces and to run it. */
+
+typedef struct _LADSPA_Descriptor { 
+
+  /* This numeric identifier indicates the plugin type
+     uniquely. Plugin programmers may reserve ranges of IDs from a
+     central body to avoid clashes. Hosts may assume that IDs are
+     below 0x1000000. */
+  unsigned long UniqueID;
+
+  /* This identifier can be used as a unique, case-sensitive
+     identifier for the plugin type within the plugin file. Plugin
+     types should be identified by file and label rather than by index
+     or plugin name, which may be changed in new plugin
+     versions. Labels must not contain white-space characters. */
+  const char * Label;
+
+  /* This indicates a number of properties of the plugin. */
+  LADSPA_Properties Properties;
+
+  /* This member points to the null-terminated name of the plugin
+     (e.g. "Sine Oscillator"). */
+  const char * Name;
+
+  /* This member points to the null-terminated string indicating the
+     maker of the plugin. This can be an empty string but not NULL. */
+  const char * Maker;
+
+  /* This member points to the null-terminated string indicating any
+     copyright applying to the plugin. If no Copyright applies the
+     string "None" should be used. */
+  const char * Copyright;
+
+  /* This indicates the number of ports (input AND output) present on
+     the plugin. */
+  unsigned long PortCount;
+
+  /* This member indicates an array of port descriptors. Valid indices
+     vary from 0 to PortCount-1. */
+  const LADSPA_PortDescriptor * PortDescriptors;
+
+  /* This member indicates an array of null-terminated strings
+     describing ports (e.g. "Frequency (Hz)"). Valid indices vary from
+     0 to PortCount-1. */
+  const char * const * PortNames;
+
+  /* This member indicates an array of range hints for each port (see
+     above). Valid indices vary from 0 to PortCount-1. */
+  const LADSPA_PortRangeHint * PortRangeHints;
+
+  /* This may be used by the plugin developer to pass any custom
+     implementation data into an instantiate call. It must not be used
+     or interpreted by the host. It is expected that most plugin
+     writers will not use this facility as LADSPA_Handle should be
+     used to hold instance data. */
+  void * ImplementationData;
+
+  /* This member is a function pointer that instantiates a plugin. A
+     handle is returned indicating the new plugin instance. The
+     instantiation function accepts a sample rate as a parameter. The
+     plugin descriptor from which this instantiate function was found
+     must also be passed. This function must return NULL if
+     instantiation fails. 
+
+     Note that instance initialisation should generally occur in
+     activate() rather than here. */
+  LADSPA_Handle (*instantiate)(const struct _LADSPA_Descriptor * Descriptor,
+                               unsigned long                     SampleRate);
+
+  /* This member is a function pointer that connects a port on an
+     instantiated plugin to a memory location at which a block of data
+     for the port will be read/written. The data location is expected
+     to be an array of LADSPA_Data for audio ports or a single
+     LADSPA_Data value for control ports. Memory issues will be
+     managed by the host. The plugin must read/write the data at these
+     locations every time run() or run_adding() is called and the data
+     present at the time of this connection call should not be
+     considered meaningful.
+
+     connect_port() may be called more than once for a plugin instance
+     to allow the host to change the buffers that the plugin is
+     reading or writing. These calls may be made before or after
+     activate() or deactivate() calls.
+
+     connect_port() must be called at least once for each port before
+     run() or run_adding() is called. When working with blocks of
+     LADSPA_Data the plugin should pay careful attention to the block
+     size passed to the run function as the block allocated may only
+     just be large enough to contain the block of samples.
+
+     Plugin writers should be aware that the host may elect to use the
+     same buffer for more than one port and even use the same buffer
+     for both input and output (see LADSPA_PROPERTY_INPLACE_BROKEN).
+     However, overlapped buffers or use of a single buffer for both
+     audio and control data may result in unexpected behaviour. */
+   void (*connect_port)(LADSPA_Handle Instance,
+                        unsigned long Port,
+                        LADSPA_Data * DataLocation);
+
+  /* This member is a function pointer that initialises a plugin
+     instance and activates it for use. This is separated from
+     instantiate() to aid real-time support and so that hosts can
+     reinitialise a plugin instance by calling deactivate() and then
+     activate(). In this case the plugin instance must reset all state
+     information dependent on the history of the plugin instance
+     except for any data locations provided by connect_port() and any
+     gain set by set_run_adding_gain(). If there is nothing for
+     activate() to do then the plugin writer may provide a NULL rather
+     than an empty function.
+
+     When present, hosts must call this function once before run() (or
+     run_adding()) is called for the first time. This call should be
+     made as close to the run() call as possible and indicates to
+     real-time plugins that they are now live. Plugins should not rely
+     on a prompt call to run() after activate(). activate() may not be
+     called again unless deactivate() is called first. Note that
+     connect_port() may be called before or after a call to
+     activate(). */
+  void (*activate)(LADSPA_Handle Instance);
+
+  /* This method is a function pointer that runs an instance of a
+     plugin for a block. Two parameters are required: the first is a
+     handle to the particular instance to be run and the second
+     indicates the block size (in samples) for which the plugin
+     instance may run.
+
+     Note that if an activate() function exists then it must be called
+     before run() or run_adding(). If deactivate() is called for a
+     plugin instance then the plugin instance may not be reused until
+     activate() has been called again.
+
+     If the plugin has the property LADSPA_PROPERTY_HARD_RT_CAPABLE
+     then there are various things that the plugin should not do
+     within the run() or run_adding() functions (see above). */
+  void (*run)(LADSPA_Handle Instance,
+              unsigned long SampleCount);
+
+  /* This method is a function pointer that runs an instance of a
+     plugin for a block. This has identical behaviour to run() except
+     in the way data is output from the plugin. When run() is used,
+     values are written directly to the memory areas associated with
+     the output ports. However when run_adding() is called, values
+     must be added to the values already present in the memory
+     areas. Furthermore, output values written must be scaled by the
+     current gain set by set_run_adding_gain() (see below) before
+     addition.
+
+     run_adding() is optional. When it is not provided by a plugin,
+     this function pointer must be set to NULL. When it is provided,
+     the function set_run_adding_gain() must be provided also. */
+  void (*run_adding)(LADSPA_Handle Instance,
+                     unsigned long SampleCount);
+
+  /* This method is a function pointer that sets the output gain for
+     use when run_adding() is called (see above). If this function is
+     never called the gain is assumed to default to 1. Gain
+     information should be retained when activate() or deactivate()
+     are called.
+
+     This function should be provided by the plugin if and only if the
+     run_adding() function is provided. When it is absent this
+     function pointer must be set to NULL. */
+  void (*set_run_adding_gain)(LADSPA_Handle Instance,
+                              LADSPA_Data   Gain);
+
+  /* This is the counterpart to activate() (see above). If there is
+     nothing for deactivate() to do then the plugin writer may provide
+     a NULL rather than an empty function.
+
+     Hosts must deactivate all activated units after they have been
+     run() (or run_adding()) for the last time. This call should be
+     made as close to the last run() call as possible and indicates to
+     real-time plugins that they are no longer live. Plugins should
+     not rely on prompt deactivation. Note that connect_port() may be
+     called before or after a call to deactivate().
+
+     Deactivation is not similar to pausing as the plugin instance
+     will be reinitialised when activate() is called to reuse it. */
+  void (*deactivate)(LADSPA_Handle Instance);
+
+  /* Once an instance of a plugin has been finished with it can be
+     deleted using the following function. The instance handle passed
+     ceases to be valid after this call.
+  
+     If activate() was called for a plugin instance then a
+     corresponding call to deactivate() must be made before cleanup()
+     is called. */
+  void (*cleanup)(LADSPA_Handle Instance);
+
+} LADSPA_Descriptor;
+
+/**********************************************************************/
+
+/* Accessing a Plugin: */
+
+/* The exact mechanism by which plugins are loaded is host-dependent,
+   however all most hosts will need to know is the name of shared
+   object file containing the plugin types. To allow multiple hosts to
+   share plugin types, hosts may wish to check for environment
+   variable LADSPA_PATH. If present, this should contain a
+   colon-separated path indicating directories that should be searched
+   (in order) when loading plugin types.
+
+   A plugin programmer must include a function called
+   "ladspa_descriptor" with the following function prototype within
+   the shared object file. This function will have C-style linkage (if
+   you are using C++ this is taken care of by the `extern "C"' clause
+   at the top of the file).
+
+   A host will find the plugin shared object file by one means or
+   another, find the ladspa_descriptor() function, call it, and
+   proceed from there.
+
+   Plugin types are accessed by index (not ID) using values from 0
+   upwards. Out of range indexes must result in this function
+   returning NULL, so the plugin count can be determined by checking
+   for the least index that results in NULL being returned. */
+
+const LADSPA_Descriptor * ladspa_descriptor(unsigned long Index);
+
+/* Datatype corresponding to the ladspa_descriptor() function. */
+typedef const LADSPA_Descriptor * 
+(*LADSPA_Descriptor_Function)(unsigned long Index);
+
+/**********************************************************************/
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LADSPA_INCLUDED */
+
+/* EOF */