From fc703f53cf3b0ca3806ecbf20d456f36b04249af Mon Sep 17 00:00:00 2001 From: Ganesh Ajjanagadde Date: Mon, 4 Jan 2016 18:40:19 -0800 Subject: [PATCH] lavfi/af_compensationdelay: replace pow(x,0.5) by sqrt(x) sqrt is faster, and is sometimes more accurate depending on the libm. Reviewed-by: Paul B Mahol Signed-off-by: Ganesh Ajjanagadde --- libavfilter/af_compensationdelay.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libavfilter/af_compensationdelay.c b/libavfilter/af_compensationdelay.c index 33ee7e4996..d5a3484317 100644 --- a/libavfilter/af_compensationdelay.c +++ b/libavfilter/af_compensationdelay.c @@ -57,7 +57,7 @@ AVFILTER_DEFINE_CLASS(compensationdelay); // The maximum distance for options #define COMP_DELAY_MAX_DISTANCE (100.0 * 100.0 + 100.0 * 1.0 + 1.0) // The actual speed of sound in normal conditions -#define COMP_DELAY_SOUND_SPEED_KM_H(temp) 1.85325 * (643.95 * pow(((temp + 273.15) / 273.15), 0.5)) +#define COMP_DELAY_SOUND_SPEED_KM_H(temp) 1.85325 * (643.95 * sqrt(((temp + 273.15) / 273.15))) #define COMP_DELAY_SOUND_SPEED_CM_S(temp) (COMP_DELAY_SOUND_SPEED_KM_H(temp) * (1000.0 * 100.0) /* cm/km */ / (60.0 * 60.0) /* s/h */) #define COMP_DELAY_SOUND_FRONT_DELAY(temp) (1.0 / COMP_DELAY_SOUND_SPEED_CM_S(temp)) // The maximum delay may be reached by this filter