From 44813d66e2c7106a36e8b4537d5b50e54d679fb4 Mon Sep 17 00:00:00 2001
From: Paul B Mahol <onemda@gmail.com>
Date: Sat, 29 Jul 2023 11:21:28 +0200
Subject: [PATCH] avfilter/avf_showcwt: make kernels symmetrical

---
 libavfilter/avf_showcwt.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavfilter/avf_showcwt.c b/libavfilter/avf_showcwt.c
index 85cb19103b..96b8841380 100644
--- a/libavfilter/avf_showcwt.c
+++ b/libavfilter/avf_showcwt.c
@@ -655,7 +655,7 @@ static int compute_kernel(AVFilterContext *ctx)
 
         memset(tkernel, 0, size * sizeof(*tkernel));
         for (int n = 0; n < size; n++) {
-            float ff, f = n-frequency;
+            float ff, f = n+0.5f-frequency;
 
             f = hsize - fabsf(f - hsize);
             ff = expf(-f*f*deviation);