add oversampler

oversampling/HIIR/FPUStageProc.h

@@ -0,0 +1,162 @@
+/*
+        StageProcFPU.h
+        Copyright (c) 2005 Laurent de Soras
+
+Template parameters:
+  - REMAINING: Number of remaining coefficients to process, >= 0
+
+  --- Legal stuff ---
+
+This program is free software. It comes without any warranty, to
+the extent permitted by applicable law. You can redistribute it
+and/or modify it under the terms of the Do What The Fuck You Want
+To Public License, Version 2, as published by Sam Hocevar. See
+http://sam.zoy.org/wtfpl/COPYING for more details.
+
+*/
+
+#pragma once
+
+namespace hiir
+{
+
+template <int REMAINING, typename T>
+class StageProcFPU
+{
+public:
+  static inline void process_sample_pos (const int nbr_coefs, T &spl_0, T &spl_1, const T coef [], T x [], T y []);
+  static inline void process_sample_neg (const int nbr_coefs, T &spl_0, T &spl_1, const T coef [], T x [], T y []);
+
+private:
+  StageProcFPU();
+  StageProcFPU(const StageProcFPU &other);
+  StageProcFPU& operator = (const StageProcFPU &other);
+  bool operator == (const StageProcFPU &other);
+  bool operator != (const StageProcFPU &other);
+
+};  // class StageProcFPU
+
+template <>
+inline void StageProcFPU <1, double>::process_sample_pos (const int nbr_coefs, double &spl_0, double &/*spl_1*/, const double coef [], double x [], double y [])
+{
+  const int last = nbr_coefs - 1;
+  const double temp = (spl_0 - y [last]) * coef [last] + x [last];
+  x [last] = spl_0;
+  y [last] = temp;
+  spl_0 = temp;
+}
+
+template <>
+inline void StageProcFPU <0, double>::process_sample_pos (const int /*nbr_coefs*/, double &/*spl_0*/, double &/*spl_1*/, const double /*coef*/ [], double /*x*/ [], double /*y*/ [])
+{
+  // Nothing (stops recursion)
+}
+  
+template <>
+inline void StageProcFPU <1, float>::process_sample_pos (const int nbr_coefs, float &spl_0, float &/*spl_1*/, const float coef [], float x [], float y [])
+{
+  const int last = nbr_coefs - 1;
+  const float temp = (spl_0 - y [last]) * coef [last] + x [last];
+  x [last] = spl_0;
+  y [last] = temp;
+  spl_0 = temp;
+}
+
+template <>
+inline void StageProcFPU <0, float>::process_sample_pos (const int /*nbr_coefs*/, float &/*spl_0*/, float &/*spl_1*/, const float /*coef*/ [], float /*x*/ [], float /*y*/ [])
+{
+  // Nothing (stops recursion)
+}
+
+template <int REMAINING, typename T>
+void  StageProcFPU <REMAINING, T>::process_sample_pos (const int nbr_coefs, T &spl_0, T &spl_1, const T coef [], T x [], T y [])
+{
+  const int   cnt = nbr_coefs - REMAINING;
+
+  const T   temp_0 =
+    (spl_0 - y [cnt + 0]) * coef [cnt + 0] + x [cnt + 0];
+  const T   temp_1 =
+    (spl_1 - y [cnt + 1]) * coef [cnt + 1] + x [cnt + 1];
+
+  x [cnt + 0] = spl_0;
+  x [cnt + 1] = spl_1;
+
+  y [cnt + 0] = temp_0;
+  y [cnt + 1] = temp_1;
+
+  spl_0 = temp_0;
+  spl_1 = temp_1;
+
+  StageProcFPU <REMAINING - 2, T>::process_sample_pos (
+    nbr_coefs,
+    spl_0,
+    spl_1,
+    &coef [0],
+    &x [0],
+    &y [0]
+  );
+}
+
+template <>
+inline void StageProcFPU <1, double>::process_sample_neg (const int nbr_coefs, double &spl_0, double &/*spl_1*/, const double coef [], double x [], double y [])
+{
+  const int last = nbr_coefs - 1;
+  const double temp = (spl_0 + y [last]) * coef [last] - x [last];
+  x [last] = spl_0;
+  y [last] = temp;
+  spl_0 = temp;
+}
+
+template <>
+inline void StageProcFPU <0, double>::process_sample_neg (const int /*nbr_coefs*/, double &/*spl_0*/, double &/*spl_1*/, const double /*coef*/ [], double /*x*/ [], double /*y*/ [])
+{
+  // Nothing (stops recursion)
+}
+  
+template <>
+inline void StageProcFPU <1, float>::process_sample_neg (const int nbr_coefs, float &spl_0, float &/*spl_1*/, const float coef [], float x [], float y [])
+{
+  const int last = nbr_coefs - 1;
+  const float temp = (spl_0 + y [last]) * coef [last] - x [last];
+  x [last] = spl_0;
+  y [last] = temp;
+  spl_0 = temp;
+}
+
+template <>
+inline void StageProcFPU <0, float>::process_sample_neg (const int /*nbr_coefs*/, float &/*spl_0*/, float &/*spl_1*/, const float /*coef*/ [], float /*x*/ [], float /*y*/ [])
+{
+  // Nothing (stops recursion)
+}
+
+template <int REMAINING, typename T>
+void  StageProcFPU <REMAINING, T>::process_sample_neg (const int nbr_coefs, T &spl_0, T &spl_1, const T coef [], T x [], T y [])
+{
+  const int cnt = nbr_coefs - REMAINING;
+
+  const T   temp_0 =
+    (spl_0 + y [cnt + 0]) * coef [cnt + 0] - x [cnt + 0];
+  const T   temp_1 =
+    (spl_1 + y [cnt + 1]) * coef [cnt + 1] - x [cnt + 1];
+
+  x [cnt + 0] = spl_0;
+  x [cnt + 1] = spl_1;
+
+  y [cnt + 0] = temp_0;
+  y [cnt + 1] = temp_1;
+
+  spl_0 = temp_0;
+  spl_1 = temp_1;
+
+  StageProcFPU <REMAINING - 2, T>::process_sample_neg (
+    nbr_coefs,
+    spl_0,
+    spl_1,
+    &coef [0],
+    &x [0],
+    &y [0]
+  );
+}
+
+
+} // namespace hiir