1 files changed, 50 insertions, 0 deletions
diff --git a/alc/filters/splitter.h b/alc/filters/splitter.h
new file mode 100644
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+++ b/alc/filters/splitter.h
@@ -0,0 +1,50 @@
+#ifndef FILTER_SPLITTER_H
+#define FILTER_SPLITTER_H
+
+#include "alcmain.h"
+#include "almalloc.h"
+
+
+/* Band splitter. Splits a signal into two phase-matching frequency bands. */
+template<typename Real>
+class BandSplitterR {
+    Real coeff{0.0f};
+    Real lp_z1{0.0f};
+    Real lp_z2{0.0f};
+    Real ap_z1{0.0f};
+
+public:
+    BandSplitterR() = default;
+    BandSplitterR(const BandSplitterR&) = default;
+    BandSplitterR(Real f0norm) { init(f0norm); }
+
+    void init(Real f0norm);
+    void clear() noexcept { lp_z1 = lp_z2 = ap_z1 = 0.0f; }
+    void process(Real *hpout, Real *lpout, const Real *input, const int count);
+
+    void applyHfScale(Real *samples, const Real hfscale, const int count);
+
+    /* The all-pass portion of the band splitter. Applies the same phase shift
+     * without splitting the signal. Note that each use of this method is
+     * indepedent, it does not track history between calls.
+     */
+    void applyAllpass(Real *samples, const int count) const;
+};
+using BandSplitter = BandSplitterR<float>;
+
+
+struct FrontStablizer {
+    static constexpr size_t DelayLength{256u};
+
+    alignas(16) float DelayBuf[MAX_OUTPUT_CHANNELS][DelayLength];
+
+    BandSplitter LFilter, RFilter;
+    alignas(16) float LSplit[2][BUFFERSIZE];
+    alignas(16) float RSplit[2][BUFFERSIZE];
+
+    alignas(16) float TempBuf[BUFFERSIZE + DelayLength];
+
+    DEF_NEWDEL(FrontStablizer)
+};
+
+#endif /* FILTER_SPLITTER_H */