kttsd/libkttsd/stretcher.h

   1 /***************************************************** vim:set ts=4 sw=4 sts=4:
   2   Description:
   3      Speeds up or slows down an audio file by stretching the audio stream.
   4      Uses the sox program to do the stretching.
   5
   6   Copyright:
   7   (C) 2004 by Gary Cramblitt <garycramblitt@comcast.net>
   8   -------------------
   9   Original author: Gary Cramblitt <garycramblitt@comcast.net>
  10
  11   This program is free software; you can redistribute it and/or modify
  12   it under the terms of the GNU General Public License as published by
  13   the Free Software Foundation; either version 2 of the License, or
  14   (at your option) any later version.
  15
  16   This program is distributed in the hope that it will be useful,
  17   but WITHOUT ANY WARRANTY; without even the implied warranty of
  18   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19   GNU General Public License for more details.
  20
  21   You should have received a copy of the GNU General Public License
  22   along with this program; if not, write to the Free Software
  23   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  24  ******************************************************************************/
  25
  26 #ifndef STRETCHER_H
  27 #define STRETCHER_H
  28
  29 #include <QObject>
  30
  31 #include <kdemacros.h>
  32
  33 class K3Process;
  34
  35 class KDE_EXPORT Stretcher : public QObject{
  36     Q_OBJECT
  37
  38     public:
  39         /**
  40          * Constructor.
  41          */
  42         explicit Stretcher(QObject *parent = 0, const char *name = 0);
  43
  44         /**
  45          * Destructor.
  46          */
  47         ~Stretcher();
  48
  49         enum StretcherState {
  50             ssIdle = 0,             // Not doing anything.  Ready to stretch.
  51             ssStretching = 1,       // Stretching.
  52             ssFinished = 2          // Stretching finished.
  53         };
  54
  55         /**
  56          * Stretch the given input file to an output file.
  57          * @param inFilename        Name of input audio file.
  58          * @param outFilename       Name of output audio file.
  59          * @param stretchFactor     Amount to stretch.  2.0 is twice as slow.  0.5 is twice as fast.
  60          */
  61         bool stretch(const QString &inFilename, const QString &outFilename, float stretchFactor);
  62
  63         /**
  64         * Returns the state of the Stretcher.
  65         */
  66         int getState();
  67
  68         /**
  69          * Returns the output filename (as given in call to stretch).
  70          */
  71         QString getOutFilename();
  72
  73         /**
  74         * Acknowledges the finished stretching.
  75         */
  76         void ackFinished();
  77
  78     signals:
  79         /**
  80          * Emitted whenever stretching is completed.
  81          */
  82         void stretchFinished();
  83
  84     private slots:
  85         void slotProcessExited(K3Process* proc);
  86
  87     private:
  88         // Stretcher state.
  89         int m_state;
  90
  91         // Sox process.
  92         K3Process* m_stretchProc;
  93
  94         // Output file name.
  95         QString m_outFilename;
  96 };
  97
  98 #endif      // STRETCHER_H