diff --git a/lib/moi/util/pdf.elv b/lib/moi/util/pdf.elv
index 84868d0..16a0644 100644
--- a/lib/moi/util/pdf.elv
+++ b/lib/moi/util/pdf.elv
@@ -49,6 +49,11 @@ fn form {|in|
   put $json[acroform]
 }
 
+fn encryption {|in|
+  var json = (json $in)
+  put $json[encrypt]
+}
+
 fn objects {|in|
   var json = (json $in)
   put $json[objects]
@@ -86,7 +91,7 @@ fn filter {|&extend=$false in cond|
 }
 
 fn trailer {|in|
-  object &extend=$true $in 'trailer'
+  object $in 'trailer'
 }
 
 fn pages {|in|
@@ -94,6 +99,10 @@ fn pages {|in|
   put $json[pages]
 }
 
+fn page {|in nb|
+  put (pages $in)[(- $nb 1)]
+}
+
 fn nb-pages {|in|
   qpdf --show-npages $in
 }