diff options
Diffstat (limited to 'libavfilter/window_func.c')
-rw-r--r-- | libavfilter/window_func.c | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/libavfilter/window_func.c b/libavfilter/window_func.c index 1931c8ea65..fcdf6ea30e 100644 --- a/libavfilter/window_func.c +++ b/libavfilter/window_func.c @@ -128,6 +128,50 @@ void ff_generate_window_func(float *lut, int N, int win_func, float *overlap) } *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); } |