/home/marsyas/marsyas/src/marsyas/ArffFileSink.cpp

/*
** Copyright (C) 2009 Stefaan Lippens <soxofaan@gmail.com>
**
** 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 "ArffFileSink.h"

#include <fstream>
#include <iomanip>

 
using std::ostringstream;
using std::ofstream;
using std::ios_base;
using std::endl;
using std::vector;
using std::fixed;
using std::setprecision;


using namespace Marsyas;

ArffFileSink::ArffFileSink(mrs_string name) : MarSystem("ArffFileSink", name)
{
    os_ = NULL;
    filename_ = "";
    decimationCounter = 0;
    addControls();
}

ArffFileSink::ArffFileSink(const ArffFileSink& a) : MarSystem(a)
{
    os_ = NULL;
    filename_ = "";
    decimationCounter = 0;

    ctrl_floatPrecision_ = getControl("mrs_natural/floatPrecision");
    ctrl_decimationFactor_ = getControl("mrs_natural/decimationFactor");
    ctrl_filename_ = getControl("mrs_string/filename");
}


ArffFileSink::~ArffFileSink()
{
    closeOutput();
}

MarSystem*
ArffFileSink::clone() const
{
    return new ArffFileSink(*this);
}

void
ArffFileSink::addControls()
{
    addControl("mrs_natural/floatPrecision", 6, ctrl_floatPrecision_);
    addControl("mrs_natural/decimationFactor", 1, ctrl_decimationFactor_);
    addControl("mrs_string/filename", "data.arff", ctrl_filename_);
}

void
ArffFileSink::myUpdate(MarControlPtr sender)
{
    MarSystem::myUpdate(sender);

    // Cache float precision and decimation for usage in myProcess().
    floatPrecision_ = ctrl_floatPrecision_->to<mrs_natural>();
    decimationFactor_ = ctrl_decimationFactor_->to<mrs_natural>();
    // Sanitize decimation factor.
    decimationFactor_ = decimationFactor_ == 0 ? 1 : decimationFactor_;
    // Reset decimation counter variable.
    decimationCounter = 0;

}

void
ArffFileSink::closeOutput()
{
    if (os_ != NULL)
    {
        os_->flush();
        os_->close();
        delete os_;
    }
    filename_ = "";
}

void
ArffFileSink::prepareOutput()
{
    // If internal file name differs from the file name we should be writing to:
    // close previous file, open a new file and write header.
    if (filename_ != ctrl_filename_->to<mrs_string>())
    {
        // Close current file.
        closeOutput();
        // Open a new output stream for the new file.
        filename_ = ctrl_filename_->to<mrs_string>();
        os_ = new ofstream;
        os_->open(filename_.c_str());
        if (os_->fail()) {
            // \todo make this cleaner, e.g. by creating and using a dedicated
            // exception for IO/file errors.
            ostringstream oss;
            oss << "[Error in " << __FILE__ << ":" << __LINE__ << "] "
                << "could not open file '" << filename_ << "' for writing.";
            throw ios_base::failure(oss.str());
        }
        // Write ARFF header.
        writeArffHeader();
    }
}


void
ArffFileSink::writeArffHeader()
{
    // General header stuff.
    (*os_) << "% ARFF file Created by Marsyas (ArffFileSink)" << endl;
    (*os_) << "@relation " << filename_ << endl;

    // Print the attributes.
    // Get and output the observation names.
    mrs_string onObsNames = ctrl_onObsNames_->to<mrs_string>();
    vector<mrs_string> attributeNames = stringSplit(onObsNames, ",");
    const mrs_natural onObservations = ctrl_onObservations_->to<mrs_natural>();
    // Print the observation names, if available.
    for (mrs_natural i = 0; i < onObservations; ++i)
    {
        if (i < (mrs_natural)attributeNames.size() && !attributeNames[i].empty())
        {
            (*os_ ) << "@attribute " << attributeNames[i] << " real" << endl;
        }
        else
        {
            (*os_ ) << "@attribute " << "untitled" << i << " real" << endl;
        }
    }

    // End of header, we are ready now for outputting the data.
    (*os_) << "\n@data" << endl;
}

void
ArffFileSink::myProcess(realvec& in, realvec& out)
{
    mrs_natural o,t;
    // Make sure we can write to the output stream.
    prepareOutput();

    // Copy input to output.
    for (t = 0; t < inSamples_; t++)
    {
        for (o = 0; o < inObservations_; o++)
        {
            out(o, t) = in(o, t);
        }
    }

    if (!ctrl_mute_->isTrue()) {
        // Write data to file.
        for (t = 0; t < inSamples_; t++)
        {
            if (decimationCounter % decimationFactor_ == 0)
            {
                for (o = 0; o < inObservations_; o++)
                {
                    (*os_) << fixed << setprecision(floatPrecision_) << out(o, t);
                    if (o < inObservations_ - 1)
                    {
                        (*os_) << ",";
                    }
                }
                (*os_) << endl;
            }
            decimationCounter ++;
        }
    }
}

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