diff --git a/libavfilter/window_func.c b/libavfilter/window_func.c
index fcdf6ea30e..acf1b20847 100644
--- a/libavfilter/window_func.c
+++ b/libavfilter/window_func.c
@@ -117,7 +117,7 @@ void ff_generate_window_func(float *lut, int N, int win_func, float *overlap)
         *overlap = 0.33;
         break;
     case WFUNC_DOLPH: {
-        double b = cosh(acosh(pow(10., 3)) / (N-1)), sum, t, c, norm = 0;
+        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)