AudioFileMemoryLoader.cxx

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/*
 * Copyright (c) 2001-2004 MUSIC TECHNOLOGY GROUP (MTG)
 *                         UNIVERSITAT POMPEU FABRA
 *
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include "AudioFileMemoryLoader.hxx"
#include <CLAM/ProcessingFactory.hxx>

#include <cmath>

namespace CLAM
{

namespace Hidden
{
        static const char * metadata[] = {
                "key", "AudioFileMemoryLoader",
                "category", "Audio File I/O",
                "description", "AudioFileMemoryLoader",
                0
        };
        static FactoryRegistrator<ProcessingFactory, AudioFileMemoryLoader> reg = metadata;
}
        
        
        AudioFileMemoryLoader::AudioFileMemoryLoader( const ProcessingConfig& cfg )
                : _output( "Samples Read", this )
                , _timeOutput( "Current Time Position", this )
                , _positionInput( "Current Time Position (%)", this )
                , _lastPosition( 0 )
                , _position( 0 )
        {
                Configure( cfg );
                _positionInput.SetBounds( 0.0, 1.0 );
        }

        AudioFileMemoryLoader::~AudioFileMemoryLoader()
        {
        }
        
        // TODO: move it to the header
        const char* AudioFileMemoryLoader::GetClassName() const
        {
                return "AudioFileMemoryLoader";
        }

        const ProcessingConfig& AudioFileMemoryLoader::GetConfig() const
        {
                return _config;
        }

        bool AudioFileMemoryLoader::ConcreteConfigure( const ProcessingConfig& cfgObject )
        {
                CopyAsConcreteConfig( _config, cfgObject );

                MonoAudioFileReader reader(_config);
                
                if ( !reader.IsConfigured() )
                {
                        AddConfigErrorMessage(reader.GetConfigErrorMessage());
                        return false;
                }

                reader.Start();
                _samples.SetSize(reader.GetHeader().GetSamples());
                reader.Do(_samples);
                
                _sampleRate = reader.GetHeader().GetSampleRate();
                _delta = 0.9 / reader.GetHeader().GetSamples();
                _position = 0;
                _timeOutput.SendControl(0);
                
                return true;
        }

        bool AudioFileMemoryLoader::ConcreteStart()
        {
                _position = 0;
                _timeOutput.SendControl(0);
                return true;
        }

        bool AudioFileMemoryLoader::Do()
        {
                bool result = Do( _output.GetAudio() );
                _output.Produce();

                return result;
        }

        bool AudioFileMemoryLoader::Do( Audio & outputSamples )
        {
                CLAM::TData * samplesArray = &_samples.GetBuffer()[0];
                CLAM::TData * outputArray = &outputSamples.GetBuffer()[0];
                
                CLAM::TControlData currentPosition = _positionInput.GetLastValue();
                if (std::fabs (currentPosition - _lastPosition) > _delta)
                {
                        _lastPosition = currentPosition;
                        _position = long(currentPosition * TControlData(_samples.GetSize()));
                }
                
                long lastSample = _samples.GetSize() - 1;
                long length = outputSamples.GetSize();
                bool loop = _config.GetLoop();
                long i = 0;
                while (i < length)
                {
                        long samplesLeft = lastSample - _position;
                        if (samplesLeft > length - i)
                                samplesLeft = length - i;
                        
                        for (; samplesLeft > 0; samplesLeft--)
                        {
                                outputArray[i] = samplesArray[_position];
                                i++;
                                _position++;
                        }
                        
                        if (!loop)
                                break;
                        
                        if (_position >= lastSample)
                                _position = 0;
                }
                
                for (; i < length; i++)
                {
                        outputArray[i] = 0.0;
                }
                
                _timeOutput.SendControl(float(_position) / _samples.GetSize());
                
                return true;
        }
        
        unsigned long AudioFileMemoryLoader::GetSamples()
        {
                return _samples.GetSize();
        }
        
}