From 988fd5743d3a286e490e1860ddef169cf8174a1b Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Tue, 23 May 2023 01:19:32 +0200 Subject: [PATCH] avcodec/kbdwin: Remove low precision intermediate in ff_kbd_window_init_fixed() Previously floats where scaled up to 32bit int, but floats do not have 32bits in their mantisse so a quarter of the bits where nonsense. It seems no fate test is affected by this change, which is interresting Signed-off-by: Michael Niedermayer --- libavcodec/kbdwin.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/libavcodec/kbdwin.c b/libavcodec/kbdwin.c index e2f6491124..163f9d5251 100644 --- a/libavcodec/kbdwin.c +++ b/libavcodec/kbdwin.c @@ -21,7 +21,7 @@ #include "libavutil/attributes.h" #include "kbdwin.h" -av_cold void ff_kbd_window_init(float *window, float alpha, int n) +av_cold static void kbd_window_init(float *float_window, int *int_window, float alpha, int n) { int i; double sum = 0.0, tmp; @@ -40,20 +40,22 @@ av_cold void ff_kbd_window_init(float *window, float alpha, int n) for (i = 0; i <= n / 2; i++) { sum += temp[i]; - window[i] = sqrt(sum * scale); + if (float_window) float_window[i] = sqrt(sum * scale); + else int_window[i] = lrint(2147483647 * sqrt(sum * scale)); } for (; i < n; i++) { sum += temp[n - i]; - window[i] = sqrt(sum * scale); + if (float_window) float_window[i] = sqrt(sum * scale); + else int_window[i] = lrint(2147483647 * sqrt(sum * scale)); } } +av_cold void ff_kbd_window_init(float *window, float alpha, int n) +{ + kbd_window_init(window, NULL, alpha, n); +} + av_cold void ff_kbd_window_init_fixed(int32_t *window, float alpha, int n) { - int i; - float local_window[FF_KBD_WINDOW_MAX]; - - ff_kbd_window_init(local_window, alpha, n); - for (i = 0; i < n; i++) - window[i] = (int)floor(2147483647.0 * local_window[i] + 0.5); + kbd_window_init(NULL, window, alpha, n); }