host-c.h
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/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */
/*
Vamp
An API for audio analysis and feature extraction plugins.
Centre for Digital Music, Queen Mary, University of London.
Copyright 2006-2015 Chris Cannam and QMUL.
Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation
files (the "Software"), to deal in the Software without
restriction, including without limitation the rights to use, copy,
modify, merge, publish, distribute, sublicense, and/or sell copies
of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR
ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
Except as contained in this notice, the names of the Centre for
Digital Music; Queen Mary, University of London; and Chris Cannam
shall not be used in advertising or otherwise to promote the sale,
use or other dealings in this Software without prior written
authorization.
*/
/*
This file defines a low-level API for enumerating and loading
plugin libraries using C calling conventions. It could be used in
C programs, or in languages with C-compatible foreign-function
interfaces. Note that this works by calling to the C++ Vamp host
SDK, so any program using this interface must still link against
the rest of the Vamp plugin library and the C++ standard library.
This is not the simplest or easiest interface for hosting Vamp
plugins -- if you have the capability to use the C++ API, please
do that instead. (Most programs should not even include this
header.)
The C and C++ interfaces provide different abstraction levels:
In the C++ interface, the class PluginLoader provides a list of
keys corresponding to the installed plugins (where a key combines
the plugin's library name and plugin identifier into a single
string) plus a method to load a single plugin based on its key
(obtaining an instance of class Plugin). With the C++ interface
you go straight from the key to a live instance of the plugin. The
PluginLoader also provides various facilities to adapt the plugin
based on your requirements (e.g. to do time- to frequency-domain
conversion for you if the plugin requires it).
This low-level C interface, on the other hand, deals only in
plugin libraries and static descriptors, not in plugin
instances. You can enumerate the installed libraries, getting just
the base .soname of each library. Then you can retrieve each of
the raw C plugin descriptors from a library, and use the
descriptor (whose interface is defined in vamp/vamp.h) to
instantiate the plugin.
So this header corresponds to the first part of the PluginLoader
class interface: finding and loading plugin libraries and
retrieving plugin descriptors from them. But it does not do any of
the rest, i.e. instantiating and adapting the plugins themselves.
Although this makes the API appear very simple, it means the
resulting plugins are relatively hard to use compared to those
obtained by the PluginLoader API. There is no way to get to the
full C++ abstraction using this API.
This API is not thread-safe; use it from a single application
thread, or guard access to it with a mutex.
This header was introduced in version 2.6 of the Vamp plugin SDK.
*/
#ifndef VAMPHOST_C_H_INCLUDED
#define VAMPHOST_C_H_INCLUDED
#include <vamp/vamp.h>
#ifdef __cplusplus
extern "C" {
#endif
typedef struct vhLibrary_t *vhLibrary;
extern int vhGetLibraryCount();
extern const char *vhGetLibraryName(int library);
extern int vhGetLibraryIndex(const char *name);
extern vhLibrary vhLoadLibrary(int library);
extern int vhGetPluginCount(vhLibrary library);
extern const VampPluginDescriptor *vhGetPluginDescriptor(vhLibrary library,
int plugin);
extern void vhUnloadLibrary(vhLibrary);
#ifdef __cplusplus
}
#endif
#endif
vhLibrary
struct vhLibrary_t * vhLibrary
Definition: host-c.h:94
vhLoadLibrary
vhLibrary vhLoadLibrary(int library)
Load the library with the given index.
_VampPluginDescriptor
Definition: vamp.h:248
vhGetLibraryCount
int vhGetLibraryCount()
Return the number of Vamp plugin libraries discovered in the installation path.
vhGetPluginCount
int vhGetPluginCount(vhLibrary library)
Return the number of Vamp plugins in the given library.
vhUnloadLibrary
void vhUnloadLibrary(vhLibrary)
Unload a plugin library.
vamp.h
vhGetLibraryIndex
int vhGetLibraryIndex(const char *name)
Return the library index for the given library name, or -1 if the name is not known.
vhGetLibraryName
const char * vhGetLibraryName(int library)
Return the library name (base soname) of the library with the given index, in the range 0....
vhGetPluginDescriptor
const VampPluginDescriptor * vhGetPluginDescriptor(vhLibrary library, int plugin)
Return a Vamp plugin descriptor for a plugin in a given library.