alc/filters/splitter.h

   1 #ifndef FILTER_SPLITTER_H
   2 #define FILTER_SPLITTER_H
   3
   4 #include <cstddef>
   5
   6
   7 /* Band splitter. Splits a signal into two phase-matching frequency bands. */
   8 template<typename Real>
   9 class BandSplitterR {
  10     Real mCoeff{0.0f};
  11     Real mLpZ1{0.0f};
  12     Real mLpZ2{0.0f};
  13     Real mApZ1{0.0f};
  14
  15 public:
  16     BandSplitterR() = default;
  17     BandSplitterR(const BandSplitterR&) = default;
  18     BandSplitterR(Real f0norm) { init(f0norm); }
  19
  20     void init(Real f0norm);
  21     void clear() noexcept { mLpZ1 = mLpZ2 = mApZ1 = 0.0f; }
  22     void process(Real *hpout, Real *lpout, const Real *input, const size_t count);
  23
  24     void applyHfScale(Real *samples, const Real hfscale, const size_t count);
  25
  26     /* The all-pass portion of the band splitter. Applies the same phase shift
  27      * without splitting the signal. Note that each use of this method is
  28      * indepedent, it does not track history between calls.
  29      */
  30     void applyAllpass(Real *samples, const size_t count) const;
  31 };
  32 using BandSplitter = BandSplitterR<float>;
  33
  34 #endif /* FILTER_SPLITTER_H */