diff options
Diffstat (limited to 'libavcodec/mdct.c')
-rw-r--r-- | libavcodec/mdct.c | 25 |
1 files changed, 0 insertions, 25 deletions
diff --git a/libavcodec/mdct.c b/libavcodec/mdct.c index c99a6cfee2..f2f34f9eda 100644 --- a/libavcodec/mdct.c +++ b/libavcodec/mdct.c @@ -30,31 +30,6 @@ * MDCT/IMDCT transforms. */ -// Generate a Kaiser-Bessel Derived Window. -#define BESSEL_I0_ITER 50 // default: 50 iterations of Bessel I0 approximation -av_cold void ff_kbd_window_init(float *window, float alpha, int n) -{ - int i, j; - double sum = 0.0, bessel, tmp; - double local_window[FF_KBD_WINDOW_MAX]; - double alpha2 = (alpha * M_PI / n) * (alpha * M_PI / n); - - assert(n <= FF_KBD_WINDOW_MAX); - - for (i = 0; i < n; i++) { - tmp = i * (n - i) * alpha2; - bessel = 1.0; - for (j = BESSEL_I0_ITER; j > 0; j--) - bessel = bessel * tmp / (j * j) + 1; - sum += bessel; - local_window[i] = sum; - } - - sum++; - for (i = 0; i < n; i++) - window[i] = sqrt(local_window[i] / sum); -} - #include "mdct_tablegen.h" /** |