diff --git a/libavfilter/vf_pixdesctest.c b/libavfilter/vf_pixdesctest.c
index 5407ec6989c4f841406becdd0eaffc07d024ea9e..cbb869c5664ba9c2c63fc359a5f6ad3131682f9b 100644
--- a/libavfilter/vf_pixdesctest.c
+++ b/libavfilter/vf_pixdesctest.c
@@ -46,6 +46,7 @@ static int config_props(AVFilterLink *inlink)
 
     priv->pix_desc = av_pix_fmt_desc_get(inlink->format);
 
+    av_freep(&priv->line);
     if (!(priv->line = av_malloc(sizeof(*priv->line) * inlink->w)))
         return AVERROR(ENOMEM);