diff --git a/lib/impression/cout.py b/lib/impression/cout.py
index 10e74671..85176336 100755
--- a/lib/impression/cout.py
+++ b/lib/impression/cout.py
@@ -87,7 +87,7 @@ def base_prix(path_pdf_file, color=False):
     nom_rep = tempfile.mkdtemp(prefix='tmpimpr')
     nom_png = "%s/convert.png" % nom_rep # Nom prefixe et chemin des png créé par convert
     escaped_path_pdf_file = escapeForShell(path_pdf_file)
-    escaped_path_ps_file = path_pdf_file + ".ps"
+    escaped_path_ps_file = escapeForShell(path_pdf_file + ".ps")
     error_msg = "ERREUR %%d : Fichier invalide. Aucun %s cree."
     if color:
         error_msg += " (couleurs)"
@@ -99,12 +99,13 @@ def base_prix(path_pdf_file, color=False):
         nb_composante = 1 # Noir
         percent_program = "percentblack"
 
-    if os.stat(path_pdf_file)[stat.ST_MTIME] > os.stat(path_pdf_file + ".ps")[stat.ST_MTIME]:
-        # Convertit les pdf en ps
-        try_command("nice -n 5 pdftops %s %s" % (escaped_path_pdf_file,
-                                                 escaped_path_ps_file),
-                    nom_rep,
-                    error_msg % "ps")
+    if not os.access(path_pdf_file + ".ps",os.F_OK) or \
+        os.stat(path_pdf_file)[stat.ST_MTIME] > os.stat(path_pdf_file + ".ps")[stat.ST_MTIME]:
+            # Convertit les pdf en ps
+            try_command("nice -n 5 pdftops %s %s" % (escaped_path_pdf_file,
+                                                     escaped_path_ps_file),
+                        nom_rep,
+                        error_msg % "ps")
 
     # Convertit les ps en png (il est néscessaire de passer par un ps
     # car ghostscript refuse certain pdf)