diff --git a/plug-ins/common/file-csource.c b/plug-ins/common/file-csource.c
index 2b79148afb..9bcc62377a 100644
--- a/plug-ins/common/file-csource.c
+++ b/plug-ins/common/file-csource.c
@@ -792,7 +792,7 @@ save_image (GFile   *file,
       if (config->use_rle)
         {
           if (! print (output, error,
-                       "%u] =\n",
+                       "%u + 1] =\n",
                        (guint) (img_buffer_end - img_buffer)))
             goto fail;
         }