lavfi: make window_func an inline function

Eliminate lavc->lavfi dependency. The function isn't big and doesn't
deserve its own file.

Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>

1 files changed, 157 insertions, 1 deletions

diff --git a/libavfilter/window_func.h b/libavfilter/window_func.h
index 4611498d47..a94482c937 100644
--- a/libavfilter/window_func.h
+++ b/libavfilter/window_func.h
@@ -22,6 +22,9 @@
 #ifndef AVFILTER_WINDOW_FUNC_H
 #define AVFILTER_WINDOW_FUNC_H
 
+#include <math.h>
+#include "libavutil/avassert.h"
+
 enum WindowFunc     { WFUNC_RECT, WFUNC_HANNING, WFUNC_HAMMING, WFUNC_BLACKMAN,
                       WFUNC_BARTLETT, WFUNC_WELCH, WFUNC_FLATTOP,
                       WFUNC_BHARRIS, WFUNC_BNUTTALL, WFUNC_SINE, WFUNC_NUTTALL,
@@ -29,6 +32,159 @@ enum WindowFunc     { WFUNC_RECT, WFUNC_HANNING, WFUNC_HAMMING, WFUNC_BLACKMAN,
                       WFUNC_DOLPH, WFUNC_CAUCHY, WFUNC_PARZEN, WFUNC_POISSON,
                       NB_WFUNC };
 
-void ff_generate_window_func(float *lut, int N, int win_func, float *overlap);
+static inline void generate_window_func(float *lut, int N, int win_func,
+                                        float *overlap)
+{
+    int n;
+
+    switch (win_func) {
+    case WFUNC_RECT:
+        for (n = 0; n < N; n++)
+            lut[n] = 1.;
+        *overlap = 0.;
+        break;
+    case WFUNC_BARTLETT:
+        for (n = 0; n < N; n++)
+            lut[n] = 1.-fabs((n-(N-1)/2.)/((N-1)/2.));
+        *overlap = 0.5;
+        break;
+    case WFUNC_HANNING:
+        for (n = 0; n < N; n++)
+            lut[n] = .5*(1-cos(2*M_PI*n/(N-1)));
+        *overlap = 0.5;
+        break;
+    case WFUNC_HAMMING:
+        for (n = 0; n < N; n++)
+            lut[n] = .54-.46*cos(2*M_PI*n/(N-1));
+        *overlap = 0.5;
+        break;
+    case WFUNC_BLACKMAN:
+        for (n = 0; n < N; n++)
+            lut[n] = .42659-.49656*cos(2*M_PI*n/(N-1))+.076849*cos(4*M_PI*n/(N-1));
+        *overlap = 0.661;
+        break;
+    case WFUNC_WELCH:
+        for (n = 0; n < N; n++)
+            lut[n] = 1.-(n-(N-1)/2.)/((N-1)/2.)*(n-(N-1)/2.)/((N-1)/2.);
+        *overlap = 0.293;
+        break;
+    case WFUNC_FLATTOP:
+        for (n = 0; n < N; n++)
+            lut[n] = 1.-1.985844164102*cos( 2*M_PI*n/(N-1))+1.791176438506*cos( 4*M_PI*n/(N-1))-
+            1.282075284005*cos( 6*M_PI*n/(N-1))+0.667777530266*cos( 8*M_PI*n/(N-1))-
+            0.240160796576*cos(10*M_PI*n/(N-1))+0.056656381764*cos(12*M_PI*n/(N-1))-
+            0.008134974479*cos(14*M_PI*n/(N-1))+0.000624544650*cos(16*M_PI*n/(N-1))-
+            0.000019808998*cos(18*M_PI*n/(N-1))+0.000000132974*cos(20*M_PI*n/(N-1));
+        *overlap = 0.841;
+        break;
+    case WFUNC_BHARRIS:
+        for (n = 0; n < N; n++)
+            lut[n] = 0.35875-0.48829*cos(2*M_PI*n/(N-1))+0.14128*cos(4*M_PI*n/(N-1))-0.01168*cos(6*M_PI*n/(N-1));
+        *overlap = 0.661;
+        break;
+    case WFUNC_BNUTTALL:
+        for (n = 0; n < N; n++)
+            lut[n] = 0.3635819-0.4891775*cos(2*M_PI*n/(N-1))+0.1365995*cos(4*M_PI*n/(N-1))-0.0106411*cos(6*M_PI*n/(N-1));
+        *overlap = 0.661;
+        break;
+    case WFUNC_BHANN:
+        for (n = 0; n < N; n++)
+            lut[n] = 0.62-0.48*fabs(n/(double)(N-1)-.5)-0.38*cos(2*M_PI*n/(N-1));
+        *overlap = 0.5;
+        break;
+    case WFUNC_SINE:
+        for (n = 0; n < N; n++)
+            lut[n] = sin(M_PI*n/(N-1));
+        *overlap = 0.75;
+        break;
+    case WFUNC_NUTTALL:
+        for (n = 0; n < N; n++)
+            lut[n] = 0.355768-0.487396*cos(2*M_PI*n/(N-1))+0.144232*cos(4*M_PI*n/(N-1))-0.012604*cos(6*M_PI*n/(N-1));
+        *overlap = 0.663;
+        break;
+    case WFUNC_LANCZOS:
+        #define SINC(x) (!(x)) ? 1 : sin(M_PI * (x))/(M_PI * (x));
+        for (n = 0; n < N; n++)
+            lut[n] = SINC((2.*n)/(N-1)-1);
+        *overlap = 0.75;
+        break;
+    case WFUNC_GAUSS:
+        #define SQR(x) ((x)*(x))
+        for (n = 0; n < N; n++)
+            lut[n] = exp(-0.5 * SQR((n-(N-1)/2)/(0.4*(N-1)/2.f)));
+        *overlap = 0.75;
+        break;
+    case WFUNC_TUKEY:
+        for (n = 0; n < N; n++) {
+            float M = (N-1)/2.;
+
+            if (FFABS(n - M) >= 0.3 * M) {
+                lut[n] = 0.5 * (1 + cos((M_PI*(FFABS(n - M) - 0.3 * M))/((1 - 0.3) * M)));
+            } else {
+                lut[n] = 1;
+            }
+        }
+        *overlap = 0.33;
+        break;
+    case WFUNC_DOLPH: {
+        double b = cosh(7.6009022095419887 / (N-1)), sum, t, c, norm = 0;
+        int j;
+        for (c = 1 - 1 / (b*b), n = (N-1) / 2; n >= 0; --n) {
+            for (sum = !n, b = t = j = 1; j <= n && sum != t; b *= (n-j) * (1./j), ++j)
+                t = sum, sum += (b *= c * (N - n - j) * (1./j));
+            sum /= (N - 1 - n), sum /= (norm = norm ? norm : sum);
+            lut[n] = sum;
+            lut[N - 1 - n] = sum;
+        }
+        *overlap = 0.5;}
+        break;
+    case WFUNC_CAUCHY:
+        for (n = 0; n < N; n++) {
+            double x = 2 * ((n / (double)(N - 1)) - .5);
+
+            if (x <= -.5 || x >= .5) {
+                lut[n] = 0;
+            } else {
+                lut[n] = FFMIN(1, fabs(1/(1+4*16*x*x)));
+            }
+        }
+        *overlap = 0.75;
+        break;
+    case WFUNC_PARZEN:
+        for (n = 0; n < N; n++) {
+            double x = 2 * ((n / (double)(N - 1)) - .5);
+
+            if (x > 0.25 && x <= 0.5) {
+                lut[n] = -2 * powf(-1 + 2 * x, 3);
+            } else if (x >= -.5 && x < -.25) {
+                lut[n] = 2 * powf(1 + 2 * x, 3);
+            } else if (x >= -.25 && x < 0) {
+                lut[n] = 1 - 24 * x * x - 48 * x * x * x;
+            } else if (x >= 0 && x <= .25) {
+                lut[n] = 1 - 24 * x * x + 48 * x * x * x;
+            } else {
+                lut[n] = 0;
+            }
+        }
+        *overlap = 0.75;
+        break;
+    case WFUNC_POISSON:
+        for (n = 0; n < N; n++) {
+            double x = 2 * ((n / (double)(N - 1)) - .5);
+
+            if (x >= 0 && x <= .5) {
+                lut[n] = exp(-6*x);
+            } else if (x < 0 && x >= -.5) {
+                lut[n] = exp(6*x);
+            } else {
+                lut[n] = 0;
+            }
+        }
+        *overlap = 0.75;
+        break;
+    default:
+        av_assert0(0);
+    }
+}
 
 #endif /* AVFILTER_WINDOW_FUNC_H */