cannam@227: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */ cannam@227: cannam@227: /* cannam@227: Vamp cannam@227: cannam@227: An API for audio analysis and feature extraction plugins. cannam@227: cannam@227: Centre for Digital Music, Queen Mary, University of London. cannam@227: Copyright 2006-2007 Chris Cannam and QMUL. cannam@227: cannam@227: Permission is hereby granted, free of charge, to any person cannam@227: obtaining a copy of this software and associated documentation cannam@227: files (the "Software"), to deal in the Software without cannam@227: restriction, including without limitation the rights to use, copy, cannam@227: modify, merge, publish, distribute, sublicense, and/or sell copies cannam@227: of the Software, and to permit persons to whom the Software is cannam@227: furnished to do so, subject to the following conditions: cannam@227: cannam@227: The above copyright notice and this permission notice shall be cannam@227: included in all copies or substantial portions of the Software. cannam@227: cannam@227: THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, cannam@227: EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF cannam@227: MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND cannam@227: NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR cannam@227: ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF cannam@227: CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION cannam@227: WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. cannam@227: cannam@227: Except as contained in this notice, the names of the Centre for cannam@227: Digital Music; Queen Mary, University of London; and Chris Cannam cannam@227: shall not be used in advertising or otherwise to promote the sale, cannam@227: use or other dealings in this Software without prior written cannam@227: authorization. cannam@227: */ cannam@227: cannam@227: #ifndef _VAMP_PLUGIN_CHANNEL_ADAPTER_H_ cannam@227: #define _VAMP_PLUGIN_CHANNEL_ADAPTER_H_ cannam@227: cannam@227: #include "PluginWrapper.h" cannam@227: cannam@227: namespace Vamp { cannam@227: cannam@227: namespace HostExt { cannam@227: cannam@227: /** cannam@227: * \class PluginChannelAdapter PluginChannelAdapter.h cannam@227: * cannam@227: * PluginChannelAdapter is a Vamp plugin adapter that implements a cannam@227: * policy for management of plugins that expect a different number of cannam@227: * input channels from the number actually available in the source cannam@227: * audio data. cannam@227: * cannam@227: * A host using PluginChannelAdapter may ignore the getMinChannelCount cannam@227: * and getMaxChannelCount reported by the plugin, and still expect the cannam@227: * plugin to run. cannam@227: * cannam@227: * PluginChannelAdapter implements the following policy: cannam@227: * cannam@227: * - If the plugin supports the provided number of channels directly, cannam@227: * PluginChannelAdapter will just run the plugin as normal. cannam@227: * cannam@227: * - If the plugin only supports exactly one channel but more than cannam@227: * one channel is provided, PluginChannelAdapter will use the mean of cannam@227: * the channels. This ensures that the resulting values remain cannam@227: * within the same magnitude range as expected for mono data. cannam@227: * cannam@227: * - If the plugin requires more than one channel but exactly one is cannam@227: * provided, the provided channel will be duplicated across all the cannam@227: * plugin input channels. cannam@227: * cannam@227: * If none of the above apply: cannam@227: * cannam@227: * - If the plugin requires more channels than are provided, the cannam@227: * minimum acceptable number of channels will be produced by adding cannam@227: * empty (zero valued) channels to those provided. cannam@227: * cannam@227: * - If the plugin requires fewer channels than are provided, the cannam@227: * maximum acceptable number of channels will be produced by cannam@227: * discarding the excess channels. cannam@227: * cannam@227: * Hosts requiring a different channel policy from the above will need cannam@227: * to implement it themselves, instead of using PluginChannelAdapter. cannam@227: * cannam@227: * Note that PluginChannelAdapter does not override the minimum and cannam@227: * maximum channel counts returned by the wrapped plugin. The host cannam@227: * will need to be aware that it is using a PluginChannelAdapter, and cannam@227: * be prepared to ignore these counts as necessary. (This contrasts cannam@227: * with the approach used in PluginInputDomainAdapter, which aims to cannam@227: * make the host completely unaware of which underlying input domain cannam@227: * is in fact in use.) cannam@227: * cannam@227: * (The rationale for this is that a host may wish to use the cannam@227: * PluginChannelAdapter but still discriminate in some way on the cannam@227: * basis of the number of channels actually supported. For example, a cannam@227: * simple stereo audio host may prefer to reject plugins that require cannam@227: * more than two channels on the grounds that doesn't actually cannam@227: * understand what they are for, rather than allow the channel adapter cannam@227: * to make a potentially meaningless channel conversion for them.) cannam@227: * cannam@227: * In every respect other than its management of channels, the cannam@227: * PluginChannelAdapter behaves identically to the plugin that it cannam@227: * wraps. The wrapped plugin will be deleted when the wrapper is cannam@227: * deleted. cannam@227: * cannam@227: * \note This class was introduced in version 1.1 of the Vamp plugin SDK. cannam@227: */ cannam@227: cannam@227: class PluginChannelAdapter : public PluginWrapper cannam@227: { cannam@227: public: cannam@227: PluginChannelAdapter(Plugin *plugin); // I take ownership of plugin cannam@227: virtual ~PluginChannelAdapter(); cannam@227: cannam@227: bool initialise(size_t channels, size_t stepSize, size_t blockSize); cannam@227: cannam@227: FeatureSet process(const float *const *inputBuffers, RealTime timestamp); cannam@227: cannam@227: /** cannam@227: * Call process(), providing interleaved audio data with the cannam@227: * number of channels passed to initialise(). The adapter will cannam@227: * de-interleave into temporary buffers as appropriate before cannam@227: * calling process(). cannam@227: * cannam@227: * \note This function was introduced in version 1.4 of the Vamp cannam@227: * plugin SDK. cannam@227: */ cannam@227: FeatureSet processInterleaved(const float *inputBuffer, RealTime timestamp); cannam@227: cannam@227: protected: cannam@227: class Impl; cannam@227: Impl *m_impl; cannam@227: }; cannam@227: cannam@227: } cannam@227: cannam@227: } cannam@227: cannam@227: #endif