Added half FFT and magnitudes

1 files changed, 34 insertions, 0 deletions

diff --git a/fft.h b/fft.h
new file mode 100644
index 0000000..f2b7038
--- /dev/null
+++ b/fft.h
@@ -0,0 +1,34 @@
+// FFT
+
+#pragma once
+
+#include <complex>
+#include <vector>
+
+namespace RIT {
+
+class FFT {
+private:
+	int mSize;
+	std::vector<int> order;
+	std::vector<std::complex<double>> expLUT;
+
+	bool mFlagHalfOnly;
+
+public:
+	FFT(int size, bool halfOnly = false);
+	std::vector<std::complex<double>> operator()(const std::vector<std::complex<double>> &v);
+
+	FFT& SetHalfOnly(bool enable);
+
+private:
+	int bitreverse(int i);
+
+	void reorder(const std::vector<std::complex<double>>& src, std::vector<std::complex<double>>& dst);
+	void fft_recursive(std::vector<std::complex<double>>::iterator X, int N);
+	void fft_half(std::vector<std::complex<double>>::iterator X, int N);
+}; // class FFT
+
+std::vector<double> magnitudes(std::vector<std::complex<double>>& v);
+
+} // namespace RIT