avfilter/vf_colorbalance: fix off by one overflow

Signed-off-by: Paul B Mahol <onemda@gmail.com>

diff --git a/libavfilter/vf_colorbalance.c b/libavfilter/vf_colorbalance.c
index 4e7476ae2f2e2ff5827eb1d9200d8290ae3bb28e..dd8189f5483ba6ae73202247b087ff985b4098dc 100644 (file)
--- a/libavfilter/vf_colorbalance.c
+++ b/libavfilter/vf_colorbalance.c
@@ -291,7 +291,7 @@ static int config_output(AVFilterLink *outlink)
 
         shadows[i] = low;
         midtones[i] = mid;
-        highlights[max - i] = low;
+        highlights[max - i - 1] = low;
     }
 
     for (i = 0; i < max; i++) {