diff --git a/.gitattributes b/.gitattributes
index 8ba6b6e091206defbf3f707b3bd415e6d406f7ff..1f08dc13b55de1d12e69eaee24080155f8c01379 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -3,6 +3,7 @@
 *.db binary
 *.gif binary
 *.gz binary
+*.pnm binary
 *.rs binary
 init_nt -text -crlf
 lib -text -crlf
diff --git a/tutorial/image_ill.pnm b/tutorial/image_ill.pnm
new file mode 100644
index 0000000000000000000000000000000000000000..3cf6ed1b38adc8d21074ed67447c571d734824b2
Binary files /dev/null and b/tutorial/image_ill.pnm differ