* Add OptionPitchHighConsistency

rubberband/RubberBandStretcher.h

@@ -182,44 +182,52 @@ public:
      *   \li \c OptionPitchHighQuality - Use the highest quality
      *   method for pitch shifting.  This method has a CPU cost
      *   approximately proportional to the required frequency shift.
+
+     *   \li \c OptionPitchHighConsistency - Use the method that gives
+     *   greatest consistency when used to create small variations in
+     *   pitch around the 1.0-ratio level.  Unlike the previous two
+     *   options, this avoids discontinuities when moving across the
+     *   1.0 pitch scale in real-time; it also consumes more CPU than
+     *   the others in the case where the pitch scale is exactly 1.0.
      */
     
     enum Option {
 
-        OptionProcessOffline   = 0x00000000,
-        OptionProcessRealTime  = 0x00000001,
+        OptionProcessOffline       = 0x00000000,
+        OptionProcessRealTime      = 0x00000001,
 
-        OptionStretchElastic   = 0x00000000,
-        OptionStretchPrecise   = 0x00000010,
+        OptionStretchElastic       = 0x00000000,
+        OptionStretchPrecise       = 0x00000010,
     
-        OptionTransientsCrisp  = 0x00000000,
-        OptionTransientsMixed  = 0x00000100,
-        OptionTransientsSmooth = 0x00000200,
+        OptionTransientsCrisp      = 0x00000000,
+        OptionTransientsMixed      = 0x00000100,
+        OptionTransientsSmooth     = 0x00000200,
 
-        OptionPhaseAdaptive    = 0x00000000,
-        OptionPhasePeakLocked  = 0x00001000,
-        OptionPhaseIndependent = 0x00002000,
+        OptionPhaseAdaptive        = 0x00000000,
+        OptionPhasePeakLocked      = 0x00001000,
+        OptionPhaseIndependent     = 0x00002000,
     
-        OptionThreadingAuto    = 0x00000000,
-        OptionThreadingNever   = 0x00010000,
-        OptionThreadingAlways  = 0x00020000,
+        OptionThreadingAuto        = 0x00000000,
+        OptionThreadingNever       = 0x00010000,
+        OptionThreadingAlways      = 0x00020000,
 
-        OptionWindowStandard   = 0x00000000,
-        OptionWindowShort      = 0x00100000,
-        OptionWindowLong       = 0x00200000,
+        OptionWindowStandard       = 0x00000000,
+        OptionWindowShort          = 0x00100000,
+        OptionWindowLong           = 0x00200000,
 
-        OptionFormantShifted   = 0x00000000,
-        OptionFormantPreserved = 0x01000000,
+        OptionFormantShifted       = 0x00000000,
+        OptionFormantPreserved     = 0x01000000,
 
-        OptionPitchHighSpeed   = 0x00000000,
-        OptionPitchHighQuality = 0x02000000
+        OptionPitchHighSpeed       = 0x00000000,
+        OptionPitchHighQuality     = 0x02000000,
+        OptionPitchHighConsistency = 0x04000000
     };
 
     typedef int Options;
 
     enum PresetOption {
-        DefaultOptions         = 0x00000000,
-        PercussiveOptions      = 0x00102000
+        DefaultOptions             = 0x00000000,
+        PercussiveOptions          = 0x00102000
     };
 
     /**

rubberband/rubberband-c.h

@@ -34,33 +34,34 @@ extern "C" {
 
 enum RubberBandOption {
 
-    RubberBandOptionProcessOffline   = 0x00000000,
-    RubberBandOptionProcessRealTime  = 0x00000001,
+    RubberBandOptionProcessOffline       = 0x00000000,
+    RubberBandOptionProcessRealTime      = 0x00000001,
 
-    RubberBandOptionStretchElastic   = 0x00000000,
-    RubberBandOptionStretchPrecise   = 0x00000010,
+    RubberBandOptionStretchElastic       = 0x00000000,
+    RubberBandOptionStretchPrecise       = 0x00000010,
     
-    RubberBandOptionTransientsCrisp  = 0x00000000,
-    RubberBandOptionTransientsMixed  = 0x00000100,
-    RubberBandOptionTransientsSmooth = 0x00000200,
+    RubberBandOptionTransientsCrisp      = 0x00000000,
+    RubberBandOptionTransientsMixed      = 0x00000100,
+    RubberBandOptionTransientsSmooth     = 0x00000200,
 
-    RubberBandOptionPhaseAdaptive    = 0x00000000,
-    RubberBandOptionPhasePeakLocked  = 0x00001000,
-    RubberBandOptionPhaseIndependent = 0x00002000,
+    RubberBandOptionPhaseAdaptive        = 0x00000000,
+    RubberBandOptionPhasePeakLocked      = 0x00001000,
+    RubberBandOptionPhaseIndependent     = 0x00002000,
     
-    RubberBandOptionThreadingAuto    = 0x00000000,
-    RubberBandOptionThreadingNever   = 0x00010000,
-    RubberBandOptionThreadingAlways  = 0x00020000,
+    RubberBandOptionThreadingAuto        = 0x00000000,
+    RubberBandOptionThreadingNever       = 0x00010000,
+    RubberBandOptionThreadingAlways      = 0x00020000,
 
-    RubberBandOptionWindowStandard   = 0x00000000,
-    RubberBandOptionWindowShort      = 0x00100000,
-    RubberBandOptionWindowLong       = 0x00200000,
+    RubberBandOptionWindowStandard       = 0x00000000,
+    RubberBandOptionWindowShort          = 0x00100000,
+    RubberBandOptionWindowLong           = 0x00200000,
 
-    RubberBandOptionFormantShifted   = 0x00000000,
-    RubberBandOptionFormantPreserved = 0x01000000,
+    RubberBandOptionFormantShifted       = 0x00000000,
+    RubberBandOptionFormantPreserved     = 0x01000000,
 
-    RubberBandOptionPitchHighQuality = 0x00000000,
-    RubberBandOptionPitchHighSpeed   = 0x02000000
+    RubberBandOptionPitchHighQuality     = 0x00000000,
+    RubberBandOptionPitchHighSpeed       = 0x02000000,
+    RubberBandOptionPitchHighConsistency = 0x04000000
 };
 
 typedef int RubberBandOptions;

src/StretcherImpl.cpp

@@ -524,7 +524,9 @@ RubberBandStretcher::Impl::configure()
         m_studyFFT->initFloat();
     }
 
-    if (m_pitchScale != 1.0 || m_realtime) {
+    if (m_pitchScale != 1.0 ||
+        (m_options & OptionPitchHighConsistency) ||
+        m_realtime) {
 
         for (size_t c = 0; c < m_channels; ++c) {
 
@@ -708,7 +710,9 @@ RubberBandStretcher::Impl::setPitchOption(Options options)
 
     Options prior = m_options;
 
-    int mask = (OptionPitchHighQuality | OptionPitchHighSpeed);
+    int mask = (OptionPitchHighQuality |
+                OptionPitchHighSpeed |
+                OptionPitchHighConsistency);
     m_options &= ~mask;
     options &= mask;
     m_options |= options;
@@ -989,8 +993,6 @@ RubberBandStretcher::Impl::process(const float *const *input, size_t samples, bo
 
     while (!allConsumed) {
 
-//        cerr << "process looping" << endl;
-
 //#ifndef NO_THREADING
 //        if (m_threaded) {
 //            pthread_mutex_lock(&m_inputProcessedMutex);
@@ -1052,6 +1054,9 @@ RubberBandStretcher::Impl::process(const float *const *input, size_t samples, bo
             }
 */
         }
+
+        if (!allConsumed) cerr << "process looping" << endl;
+
     }
     
 //    cerr << "process returning" << endl;

src/StretcherProcess.cpp

@@ -110,6 +110,8 @@ RubberBandStretcher::Impl::resampleBeforeStretching() const
 
     if (m_options & OptionPitchHighQuality) {
         return (m_pitchScale < 1.0); // better sound
+    } else if (m_options & OptionPitchHighConsistency) {
+        return false;
     } else {
         return (m_pitchScale > 1.0); // better performance
     }
@@ -145,6 +147,8 @@ RubberBandStretcher::Impl::consumeChannel(size_t c, const float *input,
         }
 
 
+//        std::cerr << "resampling on INPUT" << std::endl;
+
         toWrite = cd.resampler->resample(&input,
                                          &cd.resamplebuf,
                                          samples,
@@ -1009,7 +1013,9 @@ RubberBandStretcher::Impl::writeChunk(size_t channel, size_t shiftIncrement, boo
 
     bool resampledAlready = resampleBeforeStretching();
 
-    if (!resampledAlready && m_pitchScale != 1.0 && cd.resampler) {
+    if (!resampledAlready &&
+        (m_pitchScale != 1.0 || m_options & OptionPitchHighConsistency) &&
+        cd.resampler) {
 
         size_t reqSize = int(ceil(si / m_pitchScale));
         if (reqSize > cd.resamplebufSize) {
@@ -1024,6 +1030,8 @@ RubberBandStretcher::Impl::writeChunk(size_t channel, size_t shiftIncrement, boo
         }
 
 
+//        std::cerr << "resampling on OUTPUT" << std::endl;
+        
         size_t outframes = cd.resampler->resample(&cd.accumulator,
                                                   &cd.resamplebuf,
                                                   si,