annotate vamp-support/LoaderRequests.h @ 185:3eb00e5c76c4

Pull step & block size out into framing struct, return in config

Update the C++ code to separate out the framing parameters (step and
block size) from the configuration structure into their own structure,
as in the latest schema, and to return the accepted framing params in
the configuration response.

This also implies that the plugin stub (which adapts Piper API
back to Vamp) makes a note of the returned values,
making them available via its own getPreferredStep/BlockSize
so that the host can retry the initialise call in the case where it
failed for having the wrong values first time.

/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */

/*
    Piper C++

    An API for audio analysis and feature extraction plugins.

    Centre for Digital Music, Queen Mary, University of London.
    Copyright 2006-2016 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.
*/

#ifndef PIPER_LOADER_REQUESTS_H
#define PIPER_LOADER_REQUESTS_H

#include "PluginStaticData.h"
#include "PluginConfiguration.h"

#include <vamp-hostsdk/PluginLoader.h>

#include <map>
#include <string>
#include <iostream>

namespace piper_vamp {

class LoaderRequests
{
public:
    ListResponse
    listPluginData(ListRequest req) {

	auto loader = Vamp::HostExt::PluginLoader::getInstance();

//        std::cerr << "listPluginData: about to ask loader to list plugins" << std::endl;
        
        std::vector<std::string> keys;
        if (req.from.empty()) {
            keys = loader->listPlugins();
        } else {
            keys = loader->listPluginsIn(req.from);
        }

//        std::cerr << "listPluginData: loader listed " << keys.size() << " plugins" << std::endl;
        
	ListResponse response;
	for (std::string key: keys) {
//            std::cerr << "listPluginData: loading plugin and querying static data: " << key << std::endl;
	    Vamp::Plugin *p = loader->loadPlugin(key, 44100, 0);
	    if (!p) continue;
	    auto category = loader->getPluginCategory(key);
	    response.available.push_back
		(PluginStaticData::fromPlugin(key, category, p));
	    delete p;
	}

	return response;
    }

    LoadResponse
    loadPlugin(LoadRequest req) {

	auto loader = Vamp::HostExt::PluginLoader::getInstance();
	
	Vamp::Plugin *plugin = loader->loadPlugin(req.pluginKey,
						  req.inputSampleRate,
						  req.adapterFlags);

	LoadResponse response;
	response.plugin = plugin;
	if (!plugin) return response;

	response.plugin = plugin;
	response.staticData = PluginStaticData::fromPlugin
	    (req.pluginKey,
	     loader->getPluginCategory(req.pluginKey),
	     plugin);

	int defaultChannels = 0;
	if (plugin->getMinChannelCount() == plugin->getMaxChannelCount()) {
	    defaultChannels = int(plugin->getMinChannelCount());
	}
	
	response.defaultConfiguration = PluginConfiguration::fromPlugin
	    (plugin,
	     defaultChannels,
	     int(plugin->getPreferredStepSize()),
	     int(plugin->getPreferredBlockSize()));
	
	return response;
    }

    ConfigurationResponse
    configurePlugin(ConfigurationRequest req) {
	
	for (PluginConfiguration::ParameterMap::const_iterator i =
		 req.configuration.parameterValues.begin();
	     i != req.configuration.parameterValues.end(); ++i) {
	    req.plugin->setParameter(i->first, i->second);
	}

	if (req.configuration.currentProgram != "") {
	    req.plugin->selectProgram(req.configuration.currentProgram);
	}

	ConfigurationResponse response;

	response.plugin = req.plugin;

        if (req.configuration.framing.stepSize == 0 ||
            req.configuration.framing.blockSize == 0) {
            return response;
        }

	if (req.plugin->initialise(req.configuration.channelCount,
				   req.configuration.framing.stepSize,
				   req.configuration.framing.blockSize)) {

	    response.outputs = req.plugin->getOutputDescriptors();

            // If the Vamp plugin initialise() call succeeds, then by
            // definition it is accepting the step and block size
            // passed in
            response.framing = req.configuration.framing;

	} else {

            // If initialise() fails, one reason could be that it
            // didn't like the passed-in step and block size. If we
            // return its current preferred values here, the
            // host/client can retry with these (if they differ)
            response.framing.stepSize = req.plugin->getPreferredStepSize();
            response.framing.blockSize = req.plugin->getPreferredBlockSize();
        }

	return response;
    }
};

}

#endif