+/*
+ 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__
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; }
-
- 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;
-// 40.24 fixpoint math
-#define FIXPOINT_ONE 0x1000000
-
-class FixedPointLinearInterpolation : public Interpolation {
- protected:
- /// speed in fixed point math
- uint64_t phi;
-
- /// target speed in fixed point math
- uint64_t target_phi;
-
- std::vector<uint64_t> last_phase;
-
- // Fixed point is just an integer with an implied scaling factor.
- // In 40.24 the scaling factor is 2^24 = 16777216,
- // so a value of 10*2^24 (in integer space) is equivalent to 10.0.
- //
- // The advantage is that addition and modulus [like x = (x + y) % 2^40]
- // have no rounding errors and no drift, and just require a single integer add.
- // (swh)
-
- static const int64_t fractional_part_mask = 0xFFFFFF;
- static const Sample binary_scaling_factor = 16777216.0f;
-
- public:
-
- FixedPointLinearInterpolation () : phi (FIXPOINT_ONE), target_phi (FIXPOINT_ONE) {}
-
- void set_speed (double new_speed) {
- target_phi = (uint64_t) (FIXPOINT_ONE * fabs(new_speed));
- phi = target_phi;
- }
-
- uint64_t get_phi() { return phi; }
- uint64_t get_target_phi() { return target_phi; }
- uint64_t get_last_phase() { assert(last_phase.size()); return last_phase[0]; }
- void set_last_phase(uint64_t phase) { assert(last_phase.size()); last_phase[0] = phase; }
-
- void add_channel_to (int input_buffer_size, int output_buffer_size);
- void remove_channel_from ();
-
- nframes_t interpolate (int channel, nframes_t nframes, Sample* input, Sample* output);
- void reset ();
+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 LinearInterpolation : public Interpolation {
- protected:
-
- public:
- nframes_t interpolate (int channel, nframes_t nframes, Sample* input, Sample* output);
+class LIBARDOUR_API LinearInterpolation : public Interpolation {
+public:
+ framecnt_t interpolate (int channel, framecnt_t nframes, Sample* input, Sample* output);
};
-
-
-#define MAX_PERIOD_SIZE 4096
-/**
- * @class SplineInterpolation
- *
- * @brief interpolates using cubic spline interpolation over an input period
- *
- * Splines are piecewise cubic functions between each samples,
- * where the cubic polynomials' values, first and second derivatives are equal
- * on each sample point.
- *
- * Those conditions are equivalent of solving the linear system of equations
- * defined by the matrix equation (all indices are zero-based):
- * A * M = d
- *
- * where A has (n-2) rows and (n-2) columns
- *
- * [ 4 1 0 0 ... 0 0 0 0 ] [ M[1] ] [ 6*y[0] - 12*y[1] + 6*y[2] ]
- * [ 1 4 1 0 ... 0 0 0 0 ] [ M[2] ] [ 6*y[1] - 12*y[2] + 6*y[3] ]
- * [ 0 1 4 1 ... 0 0 0 0 ] [ M[3] ] [ 6*y[2] - 12*y[3] + 6*y[4] ]
- * [ 0 0 1 4 ... 0 0 0 0 ] [ M[4] ] [ 6*y[3] - 12*y[4] + 6*y[5] ]
- * ... * = ...
- * [ 0 0 0 0 ... 4 1 0 0 ] [ M[n-5] ] [ 6*y[n-6]- 12*y[n-5] + 6*y[n-4] ]
- * [ 0 0 0 0 ... 1 4 1 0 ] [ M[n-4] ] [ 6*y[n-5]- 12*y[n-4] + 6*y[n-3] ]
- * [ 0 0 0 0 ... 0 1 4 1 ] [ M[n-3] ] [ 6*y[n-4]- 12*y[n-3] + 6*y[n-2] ]
- * [ 0 0 0 0 ... 0 0 1 4 ] [ M[n-2] ] [ 6*y[n-3]- 12*y[n-2] + 6*y[n-1] ]
- *
- * For our purpose we use natural splines which means the boundary coefficients
- * M[0] = M[n-1] = 0
- *
- * The interpolation polynomial in the i-th interval then has the form
- * p_i(x) = a3 (x - i)^3 + a2 (x - i)^2 + a1 (x - i) + a0
- * = ((a3 * (x - i) + a2) * (x - i) + a1) * (x - i) + a0
- * where
- * a3 = (M[i+1] - M[i]) / 6
- * a2 = M[i] / 2
- * a1 = y[i+1] - y[i] - M[i+1]/6 - M[i]/3
- * a0 = y[i]
- *
- * We solve the system by LU-factoring the matrix A:
- * A = L * U:
- *
- * [ 4 1 0 0 ... 0 0 0 0 ] [ 1 0 0 0 ... 0 0 0 0 ] [ m[0] 1 0 0 ... 0 0 0 ]
- * [ 1 4 1 0 ... 0 0 0 0 ] [ l[0] 1 0 0 ... 0 0 0 0 ] [ 0 m[1] 1 0 ... 0 0 0 ]
- * [ 0 1 4 1 ... 0 0 0 0 ] [ 0 l[1] 1 0 ... 0 0 0 0 ] [ 0 0 m[2] 1 ... 0 0 0 ]
- * [ 0 0 1 4 ... 0 0 0 0 ] [ 0 0 l[2] 1 ... 0 0 0 0 ] ...
- * ... = ... * [ 0 0 0 0 ... 0 0 0 ]
- * [ 0 0 0 0 ... 4 1 0 0 ] [ 0 0 0 0 ... 1 0 0 0 ] [ 0 0 0 0 ... 1 0 0 ]
- * [ 0 0 0 0 ... 1 4 1 0 ] [ 0 0 0 0 ... l[n-6] 1 0 0 ] [ 0 0 0 0 ... m[n-5] 1 0 ]
- * [ 0 0 0 0 ... 0 1 4 1 ] [ 0 0 0 0 ... 0 l[n-5] 1 0 ] [ 0 0 0 0 ... 0 m[n-4] 1 ]
- * [ 0 0 0 0 ... 0 0 1 4 ] [ 0 0 0 0 ... 0 0 l[n-4] 1 ] [ 0 0 0 0 ... 0 0 m[n-3] ]
- *
- * where the l[i] and m[i] can be precomputed.
- *
- * Then we solve the system A * M = d by first solving the system
- * L * t = d
- * and then
- * R * M = t
- */
-class SplineInterpolation : public Interpolation {
- protected:
- double l[MAX_PERIOD_SIZE], m[MAX_PERIOD_SIZE];
-
- public:
- SplineInterpolation();
- nframes_t interpolate (int channel, nframes_t nframes, Sample* input, Sample* output);
+
+class LIBARDOUR_API CubicInterpolation : public Interpolation {
+public:
+ framecnt_t interpolate (int channel, framecnt_t nframes, Sample* input, Sample* output);
};
-class LibSamplerateInterpolation : public Interpolation {
- protected:
- std::vector<SRC_STATE*> state;
- std::vector<SRC_DATA*> data;
-
- int error;
-
- void reset_state ();
-
- public:
- LibSamplerateInterpolation ();
- ~LibSamplerateInterpolation ();
-
- void set_speed (double new_speed);
- void set_target_speed (double new_speed) {}
- double speed () const { return _speed; }
-
- void add_channel_to (int input_buffer_size, int output_buffer_size);
- void remove_channel_from ();
-
- nframes_t interpolate (int channel, nframes_t nframes, Sample* input, Sample* output);
- void reset() { reset_state (); }
+class BufferSet;
+
+class LIBARDOUR_API CubicMidiInterpolation : public Interpolation {
+public:
+ framecnt_t distance (framecnt_t nframes, bool roll = true);
};
} // namespace ARDOUR