diff --git a/assets.h b/assets.h
index 90c4956..96dcd97 100644
--- a/assets.h
+++ b/assets.h
@@ -4,7 +4,10 @@
   This file containts assets to be used in the game. Textures are stored by
   columns for cache friendliness (as rendering also happens by columns),
   4 bits per pixel, which means an index to 16 color subpalette stored at the
-  beginning of the image.
+  beginning of the image. Images can be converted to this format with the
+  provided pything script:
+
+  python img2array.py -t -c -x32 -y32 -ppalette565.png image.png
 
   by Miloslav Ciz (drummyfish), 2019