moodbar.cpp

来自「Amarok是一款在LINUX或其他类UNIX操作系统中运行的音频播放器软件。 」· C++ 代码 · 共 1,387 行 · 第 1/4 页

                QColor::Hsv ) );
            paint.drawPoint(x, y);
            paint.drawPoint(x, height - 1 - y);
          }
      }

    m_mutex.unlock();

    return m_pixmap;
}


#define NUM_HUES 12

// Read the .mood file.  Returns true if the read was successful
// and changes the state to Loaded; returns false and leaves the
// state untouched otherwise.
//
// This is based on Gav's original code.  We do the mood altering
// (AmarokConfig::AlterMood()) here, as well as calculating the
// hue-based sort.  All displayed moodbars will be reset() when
// the config is changed, so there's no harm in doing it here.
//
// This method must be called with the instance locked.
bool
Moodbar::readFile( void )
{
    if( !AmarokConfig::showMoodbar() )
      return false;

    if( m_state == Loaded )
      return true;

    QString path = moodFilename( m_bundle->url() );
    if( path.isEmpty() )
      return false;

    debug() << "Moodbar::readFile: Trying to read " << path << endl;

    QFile moodFile( path );

    if( !QFile::exists( path )  ||
        !moodFile.open( IO_ReadOnly ) )
      {
        // If the user has changed his/her preference about where to
        // store the mood files, he/she might have the .mood file
        // in the other place, so we should check there before giving
        // up.

        QString path2 = moodFilename( m_bundle->url(),
                                      !AmarokConfig::moodsWithMusic() );
        moodFile.setName( path2 );

        if( !QFile::exists( path2 )  ||
            !moodFile.open( IO_ReadOnly ) )
          return false;

        debug() << "Moodbar::readFile: Found a file at " << path2
                << " instead, using that and copying." << endl;

        moodFile.close();
        if( !copyFile( path2, path ) )
          return false;
        moodFile.setName( path );
        if( !moodFile.open( IO_ReadOnly ) )
          return false;
      }

    int r, g, b, samples = moodFile.size() / 3;
    debug() << "Moodbar::readFile: File " << path
            << " opened. Proceeding to read contents... s=" << samples << endl;

    // This would be bad.
    if( samples == 0 )
      {
        debug() << "Moodbar::readFile: File " << moodFile.name()
                << " is corrupted, removing." << endl;
        moodFile.remove();
        return false;
      }

    int huedist[360], mx = 0; // For alterMood
    int modalHue[NUM_HUES];   // For m_hueSort
    int h, s, v;

    memset( modalHue, 0, sizeof( modalHue ) );
    memset( huedist, 0, sizeof( huedist ) );

    // Read the file, keeping track of some histograms
    for( int i = 0; i < samples; i++ )
      {
        r = moodFile.getch();
        g = moodFile.getch();
        b = moodFile.getch();

        m_data.push_back( QColor( CLAMP( 0, r, 255 ),
                                  CLAMP( 0, g, 255 ),
                                  CLAMP( 0, b, 255 ), QColor::Rgb ) );

        // Make a histogram of hues
        m_data.last().getHsv( &h, &s, &v );
        modalHue[CLAMP( 0, h * NUM_HUES / 360, NUM_HUES - 1 )] += v;

        if( h < 0 ) h = 0;  else h = h % 360;
        huedist[h]++;
      }

    // Make moodier -- copied straight from Gav Wood's code
    // Here's an explanation of the algorithm:
    //
    // The "input" hue for each bar is mapped to a hue between
    // rangeStart and (rangeStart + rangeDelta).  The mapping is
    // determined by the hue histogram, huedist[], which is calculated
    // above by putting each sample into one of 360 hue bins.  The
    // mapping is such that if your histogram is concentrated on a few
    // hues that are close together, then these hues are separated,
    // and the space between spikes in the hue histogram is
    // compressed.  Here we consider a hue value to be a "spike" in
    // the hue histogram if the number of samples in that bin is
    // greater than the threshold variable.
    //
    // As an example, suppose we have 100 samples, and that
    //    threshold = 10  rangeStart = 0  rangeDelta = 288
    // Suppose that we have 10 samples at each of 99,100,101, and 200.
    // Suppose that there are 20 samples < 99, 20 between 102 and 199,
    // and 20 above 201, with no spikes.  There will be five hues in
    // the output, at hues 0, 72, 144, 216, and 288, containing the
    // following number of samples:
    //     0:   20 + 10 = 30   (range 0   - 99 )
    //     72:            10   (range 100 - 100)
    //     144:           10   (range 101 - 101)
    //     216: 10 + 20 = 30   (range 102 - 200)
    //     288:           20   (range 201 - 359)
    // The hues are now much more evenly distributed.
    //
    // After the hue redistribution is calculated, the saturation and
    // value are scaled by sat and val, respectively, which are percentage
    // values.

    if( AmarokConfig::makeMoodier() )
      {
        // Explanation of the parameters:
        //
        //   threshold: A hue value is considered to be a "spike" in the
        //     histogram if it's above this value.  Setting this value
        //     higher will tend to make the hue distribution more uniform
        //
        //   rangeStart, rangeDelta: output hues will be more or less
        //     evenly spaced between rangeStart and (rangeStart + rangeDelta)
        //
        //   sat, val: the saturation and value are scaled by these integral
        //     percentage values

        int threshold, rangeStart, rangeDelta, sat, val;
        int total = 0;
        memset( modalHue, 0, sizeof( modalHue ) );  // Recalculate this

        switch( AmarokConfig::alterMood() )
          {
          case 1: // Angry
            threshold  = samples / 360 * 9;
            rangeStart = 45;
            rangeDelta = -45;
            sat        = 200;
            val        = 100;
            break;

          case 2: // Frozen
            threshold  = samples / 360 * 1;
            rangeStart = 140;
            rangeDelta = 160;
            sat        = 50;
            val        = 100;
            break;

          default: // Happy
            threshold  = samples / 360 * 2;
            rangeStart = 0;
            rangeDelta = 359;
            sat        = 150;
            val        = 250;
          }

        debug() << "ReadMood: Applying filter t=" << threshold
                << ", rS=" << rangeStart << ", rD=" << rangeDelta
                << ", s=" << sat << "%, v=" << val << "%" << endl;

        // On average, huedist[i] = samples / 360.  This counts the
        // number of samples over the threshold, which is usually
        // 1, 2, 9, etc. times the average samples in each bin.
        // The total determines how many output hues there are,
        // evenly spaced between rangeStart and rangeStart + rangeDelta.
        for( int i = 0; i < 360; i++ )
          if( huedist[i] > threshold )
            total++;

        if( total < 360 && total > 0 )
          {
            // Remap the hue values to be between rangeStart and
            // rangeStart + rangeDelta.  Every time we see an input hue
            // above the threshold, increment the output hue by
            // (1/total) * rangeDelta.
            for( int i = 0, n = 0; i < 360; i++ )
              huedist[i] = ( ( huedist[i] > threshold ? n++ : n )
                             * rangeDelta / total + rangeStart ) % 360;

            // Now huedist is a hue mapper: huedist[h] is the new hue value
            // for a bar with hue h

            for(uint i = 0; i < m_data.size(); i++)
              {
                m_data[i].getHsv( &h, &s, &v );
                if( h < 0 ) h = 0;  else h = h % 360;
                m_data[i].setHsv( CLAMP( 0, huedist[h], 359 ),
                                  CLAMP( 0, s * sat / 100, 255 ),
                                  CLAMP( 0, v * val / 100, 255 ) );

                modalHue[CLAMP(0, huedist[h] * NUM_HUES / 360, NUM_HUES - 1)]
                  += (v * val / 100);
              }
          }
      }

    // Calculate m_hueSort.  This is a 3-digit number in base NUM_HUES,
    // where the most significant digit is the first strongest hue, the
    // second digit is the second strongest hue, and the third digit
    // is the third strongest.  This code was written by Gav Wood.

    m_hueSort = 0;
    mx = 0;
    for( int i = 1; i < NUM_HUES; i++ )
      if( modalHue[i] > modalHue[mx] )
        mx = i;
    m_hueSort = mx * NUM_HUES * NUM_HUES;
    modalHue[mx] = 0;

    mx = 0;
    for( int i = 1; i < NUM_HUES; i++ )
      if( modalHue[i] > modalHue[mx] )
        mx = i;
    m_hueSort += mx * NUM_HUES;
    modalHue[mx] = 0;

    mx = 0;
    for( int i = 1; i < NUM_HUES; i++ )
      if( modalHue[i] > modalHue[mx] )
        mx = i;
    m_hueSort += mx;


    debug() << "Moodbar::readFile: All done." << endl;

    moodFile.close();
    m_state = Loaded;

    return true;
}


// Returns where the mood file for this bundle should be located,
// based on the user preferences.  If no location can be determined,
// return QString::null.

QString
Moodbar::moodFilename( const KURL &url )
{
  return moodFilename( url, AmarokConfig::moodsWithMusic() );
}

QString
Moodbar::moodFilename( const KURL &url, bool withMusic )
{
    // No need to lock the object

    QString path;

    if( withMusic )
      {
        path = url.path();
        path.truncate(path.findRev('.'));

        if (path.isEmpty())  // Weird...
          return QString();

        path += ".mood";
        int slash = path.findRev('/') + 1;
        QString dir  = path.left(slash);
        QString file = path.right(path.length() - slash);
        path = dir + '.' + file;
      }

    else
      {
        // The moodbar file is {device id},{relative path}.mood}
        int deviceid = MountPointManager::instance()->getIdForUrl( url );
        KURL relativePath;
        MountPointManager::instance()->getRelativePath( deviceid,
            url, relativePath );
        path = relativePath.path();
        path.truncate(path.findRev('.'));

        if (path.isEmpty())  // Weird...
          return QString();

        path = QString::number( deviceid ) + ','
          + path.replace('/', ',') + ".mood";

        // Creates the path if necessary
        path = ::locateLocal( "data", "amarok/moods/" + path );
      }

    return path;
}


// Quick-n-dirty -->synchronous<-- file copy (the GUI needs its
// moodbars immediately!)
bool
Moodbar::copyFile( const QString &srcPath, const QString &dstPath )
{
  QFile file( srcPath );
  if( !file.open( IO_ReadOnly ) )
    return false;
  QByteArray contents = file.readAll();
  file.close();
  file.setName( dstPath );
  if( !file.open( IO_WriteOnly | IO_Truncate ) )
    return false;
  bool res = ( uint( file.writeBlock( contents ) ) == contents.size() );
  file.close();
  return res;
}



// Can we find the moodbar program?
bool
Moodbar::executableExists( void )
{
  return !(KStandardDirs::findExe( "moodbar" ).isNull());
}


#include "moodbar.moc"