From 5968f3d828aaf28a28763fce794020fc8239a35a Mon Sep 17 00:00:00 2001 From: "Ryan C. Gordon" Date: Thu, 26 May 2022 10:44:01 -0400 Subject: [PATCH] gen_audio_resampler_filter.c: Precalculate loop-invariant bessel(beta). Minor optimization in offline code. --- build-scripts/gen_audio_resampler_filter.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/build-scripts/gen_audio_resampler_filter.c b/build-scripts/gen_audio_resampler_filter.c index 4a343fb63..99d77957e 100644 --- a/build-scripts/gen_audio_resampler_filter.c +++ b/build-scripts/gen_audio_resampler_filter.c @@ -74,11 +74,12 @@ kaiser_and_sinc(float *table, float *diffs, const int tablelen, const double bet { const int lenm1 = tablelen - 1; const int lenm1div2 = lenm1 / 2; + const double bessel_beta = bessel(beta); int i; table[0] = 1.0f; for (i = 1; i < tablelen; i++) { - const double kaiser = bessel(beta * sqrt(1.0 - pow(((i - lenm1) / 2.0) / lenm1div2, 2.0))) / bessel(beta); + const double kaiser = bessel(beta * sqrt(1.0 - pow(((i - lenm1) / 2.0) / lenm1div2, 2.0))) / bessel_beta; table[tablelen - i] = (float) kaiser; }