diff --git a/quack.sh b/quack.sh
index 410e90f08d92a9d2ba744fb56809299ac7633517..a7686385c7a4ca5e21a164e65866a230e45ade4d 100755
--- a/quack.sh
+++ b/quack.sh
@@ -699,7 +699,7 @@ function makePreviewPage() {
         return
     fi
     
-    TOTAL_PROCESSED=$((TOTAL_PROCESSED))
+    TOTAL_PROCESSED=$((TOTAL_PROCESSED+1))
     echo " - ${P##*/} (${TOTAL_PROCESSED}/${TOTAL_IMAGES})"
 
     local ALTO_FILE="${BASE}${ALTO_EXT}"