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| author | Paul B Mahol <onemda@gmail.com> | 2015-09-15 09:13:53 +0000 |
|---|---|---|
| committer | Paul B Mahol <onemda@gmail.com> | 2015-09-15 09:28:40 +0000 |
| commit | f2b1df735ed0baa26353abe2dade67e9dc09a922 (patch) | |
| tree | a1b3badbb4e145c315b0ddc3eb73d85a741fdaa8 /libavfilter | |
| parent | 1c853d5727e287a9f83271590763b71f88681ee1 (diff) | |
| download | ffmpeg-f2b1df735ed0baa26353abe2dade67e9dc09a922.tar.gz | |
avfilter/avf_showfreqs: add lanczos and gauss windowing functions
Signed-off-by: Paul B Mahol <onemda@gmail.com>
Diffstat (limited to 'libavfilter')
| -rw-r--r-- | libavfilter/avf_showfreqs.c | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/libavfilter/avf_showfreqs.c b/libavfilter/avf_showfreqs.c index c00e4d8633..5dfa2df4d5 100644 --- a/libavfilter/avf_showfreqs.c +++ b/libavfilter/avf_showfreqs.c @@ -39,7 +39,7 @@ enum AmplitudeScale { AS_LINEAR, AS_SQRT, AS_CBRT, AS_LOG, NB_ASCALES }; enum WindowFunc { WFUNC_RECT, WFUNC_HANNING, WFUNC_HAMMING, WFUNC_BLACKMAN, WFUNC_BARTLETT, WFUNC_WELCH, WFUNC_FLATTOP, WFUNC_BHARRIS, WFUNC_BNUTTALL, WFUNC_SINE, WFUNC_NUTTALL, - WFUNC_BHANN, NB_WFUNC }; + WFUNC_BHANN, WFUNC_LANCZOS, WFUNC_GAUSS, NB_WFUNC }; typedef struct ShowFreqsContext { const AVClass *class; @@ -110,6 +110,8 @@ static const AVOption showfreqs_options[] = { { "bhann", "Bartlett-Hann", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_BHANN}, 0, 0, FLAGS, "win_func" }, { "sine", "Sine", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_SINE}, 0, 0, FLAGS, "win_func" }, { "nuttall", "Nuttall", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_NUTTALL}, 0, 0, FLAGS, "win_func" }, + { "lanczos", "Lanczos", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_LANCZOS}, 0, 0, FLAGS, "win_func" }, + { "gauss", "Gauss", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_GAUSS}, 0, 0, FLAGS, "win_func" }, { "overlap", "set window overlap", OFFSET(overlap), AV_OPT_TYPE_FLOAT, {.dbl=1.}, 0., 1., FLAGS }, { "averaging", "set time averaging", OFFSET(avg), AV_OPT_TYPE_INT, {.i64=1}, 0, INT32_MAX, FLAGS }, { "colors", "set channels colors", OFFSET(colors), AV_OPT_TYPE_STRING, {.str = "red|green|blue|yellow|orange|lime|pink|magenta|brown" }, 0, 0, FLAGS }, @@ -221,6 +223,17 @@ static void generate_window_func(float *lut, int N, int win_func, float *overlap 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: + for (n = 0; n < N; n++) + lut[n] = pow(M_E,-0.5*pow((n-(N-1)/2)/(0.4*(N-1)/2.f),2)); + *overlap = 0.75; + break; default: av_assert0(0); } |