diff --git a/tools/essai.sh b/tools/essai.sh
index 4364f277..c7410d8f 100755
--- a/tools/essai.sh
+++ b/tools/essai.sh
@@ -17,7 +17,13 @@ echo "=== " $0 " ==="
 ./fimgfx -v rot90 $TMPF bar.fimg
 }
 #  -----------------------------------------------------
+function essai_drand48
+{
+./mkfimg -v -t drand48 $TMPF 800 600
+./fimgstats -vv $TMPF
+}
+#  -----------------------------------------------------
 
-essai_rot90
+essai_drand48
 
 #  -----------------------------------------------------