even more stuff

core/src/dsp/window/blackman.h

@@ -0,0 +1,9 @@
+#pragma once
+#include "cosine.h"
+
+namespace dsp::window {
+    inline double blackman(double n, double N) {
+        const double coefs[] = { 0.42, 0.5, 0.08 };
+        return cosine(n, N, coefs, sizeof(coefs) / sizeof(double));
+    }
+}

core/src/dsp/window/blackman_harris.h

@@ -0,0 +1,10 @@
+#pragma once
+#include <math.h>
+#include "cosine.h"
+
+namespace dsp::window {
+    inline double blackmanHarris(double n, double N) {
+        const double coefs[] = { 0.35875, 0.48829, 0.14128, 0.01168 };
+        return cosine(n, N, coefs, sizeof(coefs) / sizeof(double));
+    }
+}

core/src/dsp/window/blackman_nuttall.h

@@ -0,0 +1,10 @@
+#pragma once
+#include <math.h>
+#include "cosine.h"
+
+namespace dsp::window {
+    inline double blackmanNuttall(double n, double N) {
+        const double coefs[] = { 0.3635819, 0.4891775, 0.1365995, 0.0106411 };
+        return cosine(n, N, coefs, sizeof(coefs) / sizeof(double));
+    }
+}

core/src/dsp/window/cosine.h

@@ -0,0 +1,17 @@
+#pragma once
+#include <math.h>
+#include <assert.h>
+#include "../math/constants.h"
+
+namespace dsp::window {
+    inline double cosine(double n, double N, const double* coefs, int coefCount) {
+        assert(coefCount > 0);
+        double win = 0.0;
+        double sign = 1.0;
+        for (int i = 0; i < coefCount; i++) {
+            win += sign * coefs[i] * cos((double)i * 2.0 * DB_M_PI * n / N);
+            sign = -sign;
+        }
+        return win;
+    } 
+}

core/src/dsp/window/hamming.h

@@ -0,0 +1,9 @@
+#pragma once
+#include "cosine.h"
+
+namespace dsp::window {
+    inline double hamming(double n, double N) {
+        const double coefs[] = { 0.54, 0.46 };
+        return cosine(n, N, coefs, sizeof(coefs) / sizeof(double));
+    }
+}

core/src/dsp/window/hann.h

@@ -0,0 +1,9 @@
+#pragma once
+#include "cosine.h"
+
+namespace dsp::window {
+    inline double hann(double n, double N) {
+        const double coefs[] = { 0.5, 0.5 };
+        return cosine(n, N, coefs, sizeof(coefs) / sizeof(double));
+    }
+}

core/src/dsp/window/nuttall.h

@@ -0,0 +1,9 @@
+#pragma once
+#include "cosine.h"
+
+namespace dsp::window {
+    inline double nuttall(double n, double N) {
+        const double coefs[] = { 0.355768, 0.487396, 0.144232, 0.012604 };
+        return cosine(n, N, coefs, sizeof(coefs) / sizeof(double));
+    }
+}

core/src/dsp/window/rectangular.h

@@ -0,0 +1,8 @@
+#pragma once
+#include "cosine.h"
+
+namespace dsp::window {
+    inline double rectangular(double n, double N) {
+        return 1.0;
+    }
+}