diff --git a/man/dwebp.1 b/man/dwebp.1
index b8e843e1..5a559a81 100644
--- a/man/dwebp.1
+++ b/man/dwebp.1
@@ -1,5 +1,5 @@
 .\"                                      Hey, EMACS: -*- nroff -*-
-.TH DWEBP 1 "July 20, 2012"
+.TH DWEBP 1 "August 2, 2012"
 .SH NAME
 dwebp \- decompress a WebP file to an image file
 .SH SYNOPSIS
@@ -92,3 +92,11 @@ for the Debian project (and may be used by others).
 .br
 Please refer to http://developers.google.com/speed/webp/ for additional
 information.
+.SS Output file format details
+PAM: http://netpbm.sourceforge.net/doc/pam.html
+.br
+PGM: http://netpbm.sourceforge.net/doc/pgm.html
+.br
+PPM: http://netpbm.sourceforge.net/doc/ppm.html
+.br
+PNG: http://www.libpng.org/pub/png/png-sitemap.html#info