cannam@99: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */ cannam@99: cannam@99: /* cannam@99: Vamp cannam@99: cannam@99: An API for audio analysis and feature extraction plugins. cannam@99: cannam@99: Centre for Digital Music, Queen Mary, University of London. cannam@99: Copyright 2006-2009 Chris Cannam and QMUL. cannam@99: cannam@99: Permission is hereby granted, free of charge, to any person cannam@99: obtaining a copy of this software and associated documentation cannam@99: files (the "Software"), to deal in the Software without cannam@99: restriction, including without limitation the rights to use, copy, cannam@99: modify, merge, publish, distribute, sublicense, and/or sell copies cannam@99: of the Software, and to permit persons to whom the Software is cannam@99: furnished to do so, subject to the following conditions: cannam@99: cannam@99: The above copyright notice and this permission notice shall be cannam@99: included in all copies or substantial portions of the Software. cannam@99: cannam@99: THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, cannam@99: EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF cannam@99: MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND cannam@99: NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR cannam@99: ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF cannam@99: CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION cannam@99: WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. cannam@99: cannam@99: Except as contained in this notice, the names of the Centre for cannam@99: Digital Music; Queen Mary, University of London; and Chris Cannam cannam@99: shall not be used in advertising or otherwise to promote the sale, cannam@99: use or other dealings in this Software without prior written cannam@99: authorization. cannam@99: */ cannam@99: cannam@99: #ifndef _VAMP_PLUGIN_CHANNEL_ADAPTER_H_ cannam@99: #define _VAMP_PLUGIN_CHANNEL_ADAPTER_H_ cannam@99: cannam@99: #include "hostguard.h" cannam@99: #include "PluginWrapper.h" cannam@99: cannam@99: _VAMP_SDK_HOSTSPACE_BEGIN(PluginChannelAdapter.h) cannam@99: cannam@99: namespace Vamp { cannam@99: cannam@99: namespace HostExt { cannam@99: cannam@99: /** cannam@99: * \class PluginChannelAdapter PluginChannelAdapter.h cannam@99: * cannam@99: * PluginChannelAdapter is a Vamp plugin adapter that implements a cannam@99: * policy for management of plugins that expect a different number of cannam@99: * input channels from the number actually available in the source cannam@99: * audio data. cannam@99: * cannam@99: * A host using PluginChannelAdapter may ignore the getMinChannelCount cannam@99: * and getMaxChannelCount reported by the plugin, and still expect the cannam@99: * plugin to run. cannam@99: * cannam@99: * PluginChannelAdapter implements the following policy: cannam@99: * cannam@99: * - If the plugin supports the provided number of channels directly, cannam@99: * PluginChannelAdapter will just run the plugin as normal. cannam@99: * cannam@99: * - If the plugin only supports exactly one channel but more than cannam@99: * one channel is provided, PluginChannelAdapter will use the mean of cannam@99: * the channels. This ensures that the resulting values remain cannam@99: * within the same magnitude range as expected for mono data. cannam@99: * cannam@99: * - If the plugin requires more than one channel but exactly one is cannam@99: * provided, the provided channel will be duplicated across all the cannam@99: * plugin input channels. cannam@99: * cannam@99: * If none of the above apply: cannam@99: * cannam@99: * - If the plugin requires more channels than are provided, the cannam@99: * minimum acceptable number of channels will be produced by adding cannam@99: * empty (zero valued) channels to those provided. cannam@99: * cannam@99: * - If the plugin requires fewer channels than are provided, the cannam@99: * maximum acceptable number of channels will be produced by cannam@99: * discarding the excess channels. cannam@99: * cannam@99: * Hosts requiring a different channel policy from the above will need cannam@99: * to implement it themselves, instead of using PluginChannelAdapter. cannam@99: * cannam@99: * Note that PluginChannelAdapter does not override the minimum and cannam@99: * maximum channel counts returned by the wrapped plugin. The host cannam@99: * will need to be aware that it is using a PluginChannelAdapter, and cannam@99: * be prepared to ignore these counts as necessary. (This contrasts cannam@99: * with the approach used in PluginInputDomainAdapter, which aims to cannam@99: * make the host completely unaware of which underlying input domain cannam@99: * is in fact in use.) cannam@99: * cannam@99: * (The rationale for this is that a host may wish to use the cannam@99: * PluginChannelAdapter but still discriminate in some way on the cannam@99: * basis of the number of channels actually supported. For example, a cannam@99: * simple stereo audio host may prefer to reject plugins that require cannam@99: * more than two channels on the grounds that doesn't actually cannam@99: * understand what they are for, rather than allow the channel adapter cannam@99: * to make a potentially meaningless channel conversion for them.) cannam@99: * cannam@99: * In every respect other than its management of channels, the cannam@99: * PluginChannelAdapter behaves identically to the plugin that it cannam@99: * wraps. The wrapped plugin will be deleted when the wrapper is cannam@99: * deleted. cannam@99: * cannam@99: * \note This class was introduced in version 1.1 of the Vamp plugin SDK. cannam@99: */ cannam@99: cannam@99: class PluginChannelAdapter : public PluginWrapper cannam@99: { cannam@99: public: cannam@99: /** cannam@99: * Construct a PluginChannelAdapter wrapping the given plugin. cannam@99: * The adapter takes ownership of the plugin, which will be cannam@99: * deleted when the adapter is deleted. cannam@99: */ cannam@99: PluginChannelAdapter(Plugin *plugin); cannam@99: virtual ~PluginChannelAdapter(); cannam@99: cannam@99: bool initialise(size_t channels, size_t stepSize, size_t blockSize); cannam@99: cannam@99: FeatureSet process(const float *const *inputBuffers, RealTime timestamp); cannam@99: cannam@99: /** cannam@99: * Call process(), providing interleaved audio data with the cannam@99: * number of channels passed to initialise(). The adapter will cannam@99: * de-interleave into temporary buffers as appropriate before cannam@99: * calling process(). cannam@99: * cannam@99: * \note This function was introduced in version 1.4 of the Vamp cannam@99: * plugin SDK. cannam@99: */ cannam@99: FeatureSet processInterleaved(const float *inputBuffer, RealTime timestamp); cannam@99: cannam@99: protected: cannam@99: class Impl; cannam@99: Impl *m_impl; cannam@99: }; cannam@99: cannam@99: } cannam@99: cannam@99: } cannam@99: cannam@99: _VAMP_SDK_HOSTSPACE_END(PluginChannelAdapter.h) cannam@99: cannam@99: #endif