X-Git-Url: https://git.carlh.net/gitweb/?a=blobdiff_plain;f=libs%2Fardour%2Fardour%2Finterpolation.h;h=488a5fe5b40c7a1c287131d546c2547e8435e349;hb=7a524285385d4581ad3f1e085629379e32f82fda;hp=98b6e7e775caf52fc07f18859f2d9bd7ead677dc;hpb=16b964020fdf9deda6262e7dd9048e36acc0912e;p=ardour.git

diff --git a/libs/ardour/ardour/interpolation.h b/libs/ardour/ardour/interpolation.h
index 98b6e7e775..488a5fe5b4 100644
--- a/libs/ardour/ardour/interpolation.h
+++ b/libs/ardour/ardour/interpolation.h
@@ -1,6 +1,26 @@
+/*
+    Copyright (C) 1999-2010 Paul Davis
+
+    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., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
 #include <math.h>
 #include <samplerate.h>
 
+#include "ardour/libardour_visibility.h"
 #include "ardour/types.h"
 
 #ifndef __interpolation_h__
@@ -8,58 +28,53 @@
 
 namespace ARDOUR {
 
-class Interpolation {
- protected:
-     double   _speed, _target_speed;
-
-     // the idea is that when the speed is not 1.0, we have to 
-     // interpolate between samples and then we have to store where we thought we were. 
-     // rather than being at sample N or N+1, we were at N+0.8792922
-     std::vector<double> phase;
-
-             
- public:
-     Interpolation ()  { _speed = 1.0; _target_speed = 1.0; }
-     ~Interpolation () { phase.clear(); }
- 
-     void set_speed (double new_speed)          { _speed = new_speed; _target_speed = new_speed; }
-     void set_target_speed (double new_speed)   { _target_speed = new_speed; }
-
-     double target_speed()          const { return _target_speed; }
-     double speed()                 const { return _speed; }
-     
-     void add_channel_to (int input_buffer_size, int output_buffer_size) { phase.push_back (0.0); }
-     void remove_channel_from () { phase.pop_back (); }
-
-     void reset () {
-         for (size_t i = 0; i < phase.size(); i++) {
-              phase[i] = 0.0;
-          }
-     }
-};
+class LIBARDOUR_API Interpolation {
+protected:
+	double _speed;
+	double _target_speed;
+
+	// the idea is that when the speed is not 1.0, we have to
+	// interpolate between samples and then we have to store where we thought we were.
+	// rather than being at sample N or N+1, we were at N+0.8792922
+	std::vector<double> phase;
 
-class LinearInterpolation : public Interpolation {
- protected:
-    
- public:
-     nframes_t interpolate (int channel, nframes_t nframes, Sample* input, Sample* output);
+public:
+	Interpolation ()  { _speed = 1.0; _target_speed = 1.0; }
+	virtual ~Interpolation() {}
+
+	void set_speed (double new_speed)          { _speed = new_speed; _target_speed = new_speed; }
+	void set_target_speed (double new_speed)   { _target_speed = new_speed; }
+
+	double target_speed()          const { return _target_speed; }
+	double speed()                 const { return _speed; }
+
+	void add_channel ()    { phase.push_back (0.0); }
+	void remove_channel () { phase.pop_back (); }
+
+	virtual void reset () {
+		for (size_t i = 0; i < phase.size(); i++) {
+			phase[i] = 0.0;
+		}
+	}
 };
 
-class CubicInterpolation : public Interpolation {
- protected:
-    // shamelessly ripped from Steve Harris' swh-plugins (ladspa-util.h)
-    static inline float cube_interp(const float fr, const float inm1, const float
-                                    in, const float inp1, const float inp2)
-    {
-        return in + 0.5f * fr * (inp1 - inm1 +
-         fr * (4.0f * inp1 + 2.0f * inm1 - 5.0f * in - inp2 +
-         fr * (3.0f * (in - inp1) - inm1 + inp2)));
-    }
-    
- public:
-     nframes_t interpolate (int channel, nframes_t nframes, Sample* input, Sample* output);
+class LIBARDOUR_API CubicInterpolation : public Interpolation {
+  public:
+	CubicInterpolation ();
+	samplecnt_t interpolate (int channel, samplecnt_t input_samples, Sample* input, samplecnt_t & output_samples, Sample* output);
+	samplecnt_t distance (samplecnt_t nframes);
+	void reset ();
+
+  private:
+	Sample z[4];
+	char   valid_z_bits;
+
+	bool is_valid (int n) const { return valid_z_bits & (1<<n); }
+	bool invalid (int n) const  { return !is_valid (n); }
+	void validate (int n)       { valid_z_bits |= (1<<n); }
+	void invalidate (int n)     { valid_z_bits &= (1<<n); }
 };
- 
+
 } // namespace ARDOUR
 
 #endif