cannam@110: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */ cannam@110: cannam@110: /* cannam@110: Vamp cannam@110: cannam@110: An API for audio analysis and feature extraction plugins. cannam@110: cannam@110: Centre for Digital Music, Queen Mary, University of London. cannam@110: Copyright 2006-2009 Chris Cannam and QMUL. cannam@110: cannam@110: Permission is hereby granted, free of charge, to any person cannam@110: obtaining a copy of this software and associated documentation cannam@110: files (the "Software"), to deal in the Software without cannam@110: restriction, including without limitation the rights to use, copy, cannam@110: modify, merge, publish, distribute, sublicense, and/or sell copies cannam@110: of the Software, and to permit persons to whom the Software is cannam@110: furnished to do so, subject to the following conditions: cannam@110: cannam@110: The above copyright notice and this permission notice shall be cannam@110: included in all copies or substantial portions of the Software. cannam@110: cannam@110: THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, cannam@110: EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF cannam@110: MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND cannam@110: NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR cannam@110: ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF cannam@110: CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION cannam@110: WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. cannam@110: cannam@110: Except as contained in this notice, the names of the Centre for cannam@110: Digital Music; Queen Mary, University of London; and Chris Cannam cannam@110: shall not be used in advertising or otherwise to promote the sale, cannam@110: use or other dealings in this Software without prior written cannam@110: authorization. cannam@110: */ cannam@110: cannam@110: #ifndef _VAMP_PLUGIN_CHANNEL_ADAPTER_H_ cannam@110: #define _VAMP_PLUGIN_CHANNEL_ADAPTER_H_ cannam@110: cannam@110: #include "hostguard.h" cannam@110: #include "PluginWrapper.h" cannam@110: cannam@110: _VAMP_SDK_HOSTSPACE_BEGIN(PluginChannelAdapter.h) cannam@110: cannam@110: namespace Vamp { cannam@110: cannam@110: namespace HostExt { cannam@110: cannam@110: /** cannam@110: * \class PluginChannelAdapter PluginChannelAdapter.h cannam@110: * cannam@110: * PluginChannelAdapter is a Vamp plugin adapter that implements a cannam@110: * policy for management of plugins that expect a different number of cannam@110: * input channels from the number actually available in the source cannam@110: * audio data. cannam@110: * cannam@110: * A host using PluginChannelAdapter may ignore the getMinChannelCount cannam@110: * and getMaxChannelCount reported by the plugin, and still expect the cannam@110: * plugin to run. cannam@110: * cannam@110: * PluginChannelAdapter implements the following policy: cannam@110: * cannam@110: * - If the plugin supports the provided number of channels directly, cannam@110: * PluginChannelAdapter will just run the plugin as normal. cannam@110: * cannam@110: * - If the plugin only supports exactly one channel but more than cannam@110: * one channel is provided, PluginChannelAdapter will use the mean of cannam@110: * the channels. This ensures that the resulting values remain cannam@110: * within the same magnitude range as expected for mono data. cannam@110: * cannam@110: * - If the plugin requires more than one channel but exactly one is cannam@110: * provided, the provided channel will be duplicated across all the cannam@110: * plugin input channels. cannam@110: * cannam@110: * If none of the above apply: cannam@110: * cannam@110: * - If the plugin requires more channels than are provided, the cannam@110: * minimum acceptable number of channels will be produced by adding cannam@110: * empty (zero valued) channels to those provided. cannam@110: * cannam@110: * - If the plugin requires fewer channels than are provided, the cannam@110: * maximum acceptable number of channels will be produced by cannam@110: * discarding the excess channels. cannam@110: * cannam@110: * Hosts requiring a different channel policy from the above will need cannam@110: * to implement it themselves, instead of using PluginChannelAdapter. cannam@110: * cannam@110: * Note that PluginChannelAdapter does not override the minimum and cannam@110: * maximum channel counts returned by the wrapped plugin. The host cannam@110: * will need to be aware that it is using a PluginChannelAdapter, and cannam@110: * be prepared to ignore these counts as necessary. (This contrasts cannam@110: * with the approach used in PluginInputDomainAdapter, which aims to cannam@110: * make the host completely unaware of which underlying input domain cannam@110: * is in fact in use.) cannam@110: * cannam@110: * (The rationale for this is that a host may wish to use the cannam@110: * PluginChannelAdapter but still discriminate in some way on the cannam@110: * basis of the number of channels actually supported. For example, a cannam@110: * simple stereo audio host may prefer to reject plugins that require cannam@110: * more than two channels on the grounds that doesn't actually cannam@110: * understand what they are for, rather than allow the channel adapter cannam@110: * to make a potentially meaningless channel conversion for them.) cannam@110: * cannam@110: * In every respect other than its management of channels, the cannam@110: * PluginChannelAdapter behaves identically to the plugin that it cannam@110: * wraps. The wrapped plugin will be deleted when the wrapper is cannam@110: * deleted. cannam@110: * cannam@110: * \note This class was introduced in version 1.1 of the Vamp plugin SDK. cannam@110: */ cannam@110: cannam@110: class PluginChannelAdapter : public PluginWrapper cannam@110: { cannam@110: public: cannam@110: /** cannam@110: * Construct a PluginChannelAdapter wrapping the given plugin. cannam@110: * The adapter takes ownership of the plugin, which will be cannam@110: * deleted when the adapter is deleted. cannam@110: */ cannam@110: PluginChannelAdapter(Plugin *plugin); cannam@110: virtual ~PluginChannelAdapter(); cannam@110: cannam@110: bool initialise(size_t channels, size_t stepSize, size_t blockSize); cannam@110: cannam@110: FeatureSet process(const float *const *inputBuffers, RealTime timestamp); cannam@110: cannam@110: /** cannam@110: * Call process(), providing interleaved audio data with the cannam@110: * number of channels passed to initialise(). The adapter will cannam@110: * de-interleave into temporary buffers as appropriate before cannam@110: * calling process(). cannam@110: * cannam@110: * \note This function was introduced in version 1.4 of the Vamp cannam@110: * plugin SDK. cannam@110: */ cannam@110: FeatureSet processInterleaved(const float *inputBuffer, RealTime timestamp); cannam@110: cannam@110: protected: cannam@110: class Impl; cannam@110: Impl *m_impl; cannam@110: }; cannam@110: cannam@110: } cannam@110: cannam@110: } cannam@110: cannam@110: _VAMP_SDK_HOSTSPACE_END(PluginChannelAdapter.h) cannam@110: cannam@110: #endif