diff --git a/lib/moi/util/pdf.elv b/lib/moi/util/pdf.elv
new file mode 100644
index 0000000..84868d0
--- /dev/null
+++ b/lib/moi/util/pdf.elv
@@ -0,0 +1,284 @@
+use path
+use re
+use str
+
+fn is-pdf {|file|
+  eq (path:ext $file) '.pdf'
+}
+
+fn exist {|file|
+  or (path:is-dir &follow-symlink=$true $file) (path:is-regular &follow-symlink=$true $file)
+}
+
+fn not-exist {|file|
+  not (exist $file)
+}
+
+fn is-pdf-exist {|file|
+  and (is-pdf $file) (exist $file)
+}
+
+fn is-number {|v|
+  re:match '^\d+$' (to-string $v)
+}
+
+fn is-page-selection {|v|
+  re:match '^(r?\d+|z)(-(r?\d+|z))?(,(r?\d+|z)(-(r?\d+|z))?)*(:(even|odd))?$' (to-string $v)
+}
+
+fn is-rotate-selection {|v|
+  re:match '^(\+|-)?\d+(:(r?\d+|z)(-(r?\d+|z))?(,(r?\d+|z)(-(r?\d+|z))?)*(:(even|odd))?)?$' (to-string $v)
+}
+
+fn is-selection {|v|
+  or (is-page-selection $v) (is-rotate-selection $v)
+}
+
+fn version {|in|
+  var version    = (head -n 1 $in)
+  set version @_ = (str:split "\r" $version)
+  str:trim-prefix $version '%PDF-'
+}
+
+fn json {|in|
+  qpdf $in --json | from-json
+}
+
+fn form {|in|
+  var json = (json $in)
+  put $json[acroform]
+}
+
+fn objects {|in|
+  var json = (json $in)
+  put $json[objects]
+}
+
+fn -object {|extend objects key|
+  if (not (has-key $objects $key)) {
+    put $nil
+    return
+  }
+  var o = $objects[$key]
+  if (and $extend (eq (kind-of $o) 'map')) {
+    keys $o | each {|k|
+      var v = $o[$k]
+      if (has-key $objects $v) {
+        set o[$k] = (-object $extend $objects $v)
+      }
+    }
+  }
+  put $o
+}
+
+fn object {|&extend=$false in key|
+  -object $extend (objects $in) $key
+}
+
+fn filter {|&extend=$false in cond|
+  var objects = (objects $in)
+  keys $objects | each {|k|
+    var o = (-object $extend $objects $k)
+    if ($cond $o) {
+      put [&id=$k &object=$o]
+    }
+  }
+}
+
+fn trailer {|in|
+  object &extend=$true $in 'trailer'
+}
+
+fn pages {|in|
+  var json = (json $in)
+  put $json[pages]
+}
+
+fn nb-pages {|in|
+  qpdf --show-npages $in
+}
+
+fn parse-selection {|@selection|
+  var out = []
+  var in  = $nil
+  each {|e|
+    if (is-pdf $e) {
+      if (not-exist $e) {
+        fail (printf '%s: le fichier n’existe pas' $e)
+      }
+      if (not-eq $in $nil) {
+        set @out = $@out $in
+      }
+      set in = [
+        &file=$e
+        &rotate=$nil
+        &selections=[]
+      ]
+      continue
+    }
+    if (eq $in $nil) {
+      fail (printf '%s: pas de fichier avant la sélection' $e)
+    }
+    var r rc = $in[rotate] $nil
+    if (is-page-selection $e) {
+      set rc = $false
+    } elif (is-rotate-selection $e) {
+      set rc = $true
+    } else {
+      fail (printf '%s: paramètre invalide' $e)
+    }
+    if (not-eq $r $rc) {
+      if (not-eq $r $nil) {
+        set @out           = $@out $in
+        set in[selections] = []
+      }
+      set in[rotate] = $rc
+    }
+    set in[selections] = [ (all $in[selections]) $e ]
+  } $selection
+  if (not-eq $in $nil) {
+    set @out = $@out $in
+  }
+  put $out
+}
+
+fn -t {
+  mktemp -q /tmp/qpdf_XXXXXXXXXX.pdf
+}
+
+fn rotate {|&empty=$false &out=$nil &keep=$false in @rotate|
+  var @args = $in
+  if (eq $out $nil) {
+    set @args = $@args --replace-input
+  } else {
+    set @args = $@args $out
+  }
+  if $empty {
+    set @args = $@args --empty
+  }
+  if $keep {
+    set @rotate = (each {|r| put --rotate=$r } $rotate)
+    qpdf $@args $@rotate
+    return
+  }
+  var tmp = []
+  try {
+    var @tmp = (each {|r|
+      var t r @s = (-t) (str:split ':' $r)
+      set s = (str:join ':' $s)
+      if (eq $s '') {
+        qpdf $in $t --rotate=$r
+      } else {
+        qpdf $in $t --pages $in $s --
+        qpdf $t --replace-input --rotate=$r
+      }
+      put $t
+    } $rotate)
+    qpdf $@args --pages $@tmp --
+  } finally {
+    rm -f $@tmp
+  }
+}
+
+fn -catarg {|selection|
+  var f r s   = $selection[file] $selection[rotate] $selection[selections]
+  var out tmp = [] []
+  if $r {
+    var t    = (-t)
+    set @tmp = $t
+    set @out = $@out $t
+    rotate &out=$t $f $@s
+  } else {
+    set @out = $@out $f
+    if (> (count $s) 0) {
+      set @out = $@out (str:join ',' $s)
+    }
+  }
+  put $out $tmp
+}
+
+fn cat {|&empty=$false &collate=$nil &out=$nil @selection|
+  var inputs    = (parse-selection $@selection)
+  var pages tmp = [] []
+  each {|in|
+    var a t    = (-catarg $in)
+    set @pages = $@pages $@a
+    set @tmp   = $@tmp $@t
+  } $inputs
+  try {
+    var in    = $pages[0]
+    var @args = $in
+    if (eq $out $nil) {
+      set @args = $@args --replace-input
+    } else {
+      set @args = $@args $out
+    }
+    if $empty {
+      set @args = $@args --empty
+    }
+    if (bool $collate) {
+      var c = --collate
+      if (is-number $collate) {
+        set c = (str:join '=' [ $c $collate ])
+      }
+      set @args = $@args $c
+    }
+    qpdf $@args --pages $@pages --
+  } finally {
+    each {|t|
+      rm -f $t
+    } $tmp
+  }
+}
+
+fn decrypt {|&out=$nil in @passwd|
+  var @args = $in
+  if (eq $out $nil) {
+    set @args = $@args --replace-input
+  } else {
+    set @args = $@args $out
+  }
+  set @args = $@args --decrypt
+  if (> (count $passwd) 0) {
+    set @args = $@args $passwd[0]
+  }
+  qpdf $@args
+}
+
+fn -l0 {|n size|
+  set n = (to-string $n)
+  var l = (- $size (count $n))
+  str:join '' [ (repeat $l 0) $n ]
+}
+
+fn split {|&empty=$false &size=1 in out|
+  if (not-exist $out) {
+    mkdir $out
+  }
+  var args = []
+  if $empty {
+    set @args = --empty
+  }
+  qpdf $@args --split-pages=$size $in $out'/%d.pdf'
+}
+
+fn uncat {|&empty=$false in out @selection|
+  if (not-exist $out) {
+    mkdir $out
+  }
+  var i = 1
+  var n = (count $selection)
+  set n = (count (to-string $n))
+  each {|s|
+    cat &empty=$empty &out=$out'/'(-l0 $i $n)'.pdf' $in $s
+    set i = (+ $i 1)
+  } $selection
+}
+
+fn raw-stream {|in out id|
+  qpdf $in --show-object=$id --raw-stream-data > $out
+}
+
+fn filtered-stream {|in out id|
+  qpdf $in --show-object=$id --filtered-stream-data --normalize-content=n --stream-data=uncompress --decode-level=all > $out
+}