From 372647aed04b89def4e73ae29df0fef60a2f1930 Mon Sep 17 00:00:00 2001 From: Justin Ruggles Date: Sat, 26 May 2012 14:50:02 -0400 Subject: lavr: resampling: add filter type and Kaiser window beta to AVOptions --- libavresample/resample.c | 27 ++++++++++++++------------- 1 file changed, 14 insertions(+), 13 deletions(-) (limited to 'libavresample/resample.c') diff --git a/libavresample/resample.c b/libavresample/resample.c index 5529fafe8d..7316e4ec60 100644 --- a/libavresample/resample.c +++ b/libavresample/resample.c @@ -30,7 +30,6 @@ #define FELEM float #define FELEM2 float #define FELEML float -#define WINDOW_TYPE 24 #elifdef CONFIG_RESAMPLE_S32 /* s32 template */ #define FILTER_SHIFT 30 @@ -39,7 +38,6 @@ #define FELEML int64_t #define FELEM_MAX INT32_MAX #define FELEM_MIN INT32_MIN -#define WINDOW_TYPE 12 #else /* s16 template */ #define FILTER_SHIFT 15 @@ -48,7 +46,6 @@ #define FELEML int64_t #define FELEM_MAX INT16_MAX #define FELEM_MIN INT16_MIN -#define WINDOW_TYPE 9 #endif struct ResampleContext { @@ -65,6 +62,8 @@ struct ResampleContext { int phase_shift; int phase_mask; int linear; + enum AVResampleFilterType filter_type; + int kaiser_beta; double factor; }; @@ -95,13 +94,13 @@ static double bessel(double x) * @param tap_count tap count * @param phase_count phase count * @param scale wanted sum of coefficients for each filter - * @param type 0->cubic - * 1->blackman nuttall windowed sinc - * 2..16->kaiser windowed sinc beta=2..16 + * @param filter_type filter type + * @param kaiser_beta kaiser window beta * @return 0 on success, negative AVERROR code on failure */ static int build_filter(FELEM *filter, double factor, int tap_count, - int phase_count, int scale, int type) + int phase_count, int scale, int filter_type, + int kaiser_beta) { int ph, i; double x, y, w; @@ -122,23 +121,23 @@ static int build_filter(FELEM *filter, double factor, int tap_count, x = M_PI * ((double)(i - center) - (double)ph / phase_count) * factor; if (x == 0) y = 1.0; else y = sin(x) / x; - switch (type) { - case 0: { + switch (filter_type) { + case AV_RESAMPLE_FILTER_TYPE_CUBIC: { const float d = -0.5; //first order derivative = -0.5 x = fabs(((double)(i - center) - (double)ph / phase_count) * factor); if (x < 1.0) y = 1 - 3 * x*x + 2 * x*x*x + d * ( -x*x + x*x*x); else y = d * (-4 + 8 * x - 5 * x*x + x*x*x); break; } - case 1: + case AV_RESAMPLE_FILTER_TYPE_BLACKMAN_NUTTALL: w = 2.0 * x / (factor * tap_count) + M_PI; y *= 0.3635819 - 0.4891775 * cos( w) + 0.1365995 * cos(2 * w) - 0.0106411 * cos(3 * w); break; - default: + case AV_RESAMPLE_FILTER_TYPE_KAISER: w = 2.0 * x / (factor * tap_count * M_PI); - y *= bessel(type * sqrt(FFMAX(1 - w * w, 0))); + y *= bessel(kaiser_beta * sqrt(FFMAX(1 - w * w, 0))); break; } @@ -186,13 +185,15 @@ ResampleContext *ff_audio_resample_init(AVAudioResampleContext *avr) c->linear = avr->linear_interp; c->factor = factor; c->filter_length = FFMAX((int)ceil(avr->filter_size / factor), 1); + c->filter_type = avr->filter_type; + c->kaiser_beta = avr->kaiser_beta; c->filter_bank = av_mallocz(c->filter_length * (phase_count + 1) * sizeof(FELEM)); if (!c->filter_bank) goto error; if (build_filter(c->filter_bank, factor, c->filter_length, phase_count, - 1 << FILTER_SHIFT, WINDOW_TYPE) < 0) + 1 << FILTER_SHIFT, c->filter_type, c->kaiser_beta) < 0) goto error; memcpy(&c->filter_bank[c->filter_length * phase_count + 1], -- cgit v1.2.3