diff --git a/lib/Alchemy/Phrasea/Filesystem/FilesystemService.php b/lib/Alchemy/Phrasea/Filesystem/FilesystemService.php
index b0e9d610be..fe2ac305c9 100644
--- a/lib/Alchemy/Phrasea/Filesystem/FilesystemService.php
+++ b/lib/Alchemy/Phrasea/Filesystem/FilesystemService.php
@@ -67,18 +67,18 @@ class FilesystemService
         return $pathdest . $this->generateSubdefFilename($record, $subdef);
     }
 
-    public function generateTemporarySubdefPathname(\record_adapter $record, \databox_subdef $subdef, $tmpDir)
+    public function generateTemporaryFfmpegPathname(\record_adapter $record, \databox_subdef $subdef, $tmpDir)
     {
         $tmpDir = \p4string::addEndSlash($tmpDir);
-        $tmpDir = $tmpDir.$subdef->getSpecs()->getType()."/";
+        $ffmpegDir = $tmpDir."ffmpeg/";
 
-        if(!is_dir($tmpDir)){
-            $this->filesystem->mkdir($tmpDir);
+        if(!is_dir($ffmpegDir)){
+            $this->filesystem->mkdir($ffmpegDir);
         }
 
         $filenameSufix = "_".$record->getDataboxId()."_".$this->generateSubdefFilename($record, $subdef);
 
-        return $tmpDir . hash('sha256', $filenameSufix) . $filenameSufix;
+        return $ffmpegDir . hash('sha256', $filenameSufix) . $filenameSufix;
     }
 
     /**
diff --git a/lib/Alchemy/Phrasea/Media/SubdefGenerator.php b/lib/Alchemy/Phrasea/Media/SubdefGenerator.php
index 68285a3c63..94631fd03d 100644
--- a/lib/Alchemy/Phrasea/Media/SubdefGenerator.php
+++ b/lib/Alchemy/Phrasea/Media/SubdefGenerator.php
@@ -178,9 +178,9 @@ class SubdefGenerator
 
             $destFile = null;
 
-            if(!empty($this->tmpDirectory)){
+            if($subdef_class->getSpecs() instanceof Video && !empty($this->tmpDirectory)){
                 $destFile = $pathdest;
-                $pathdest = $this->filesystem->generateTemporarySubdefPathname($record, $subdef_class, $this->tmpDirectory);
+                $pathdest = $this->filesystem->generateTemporaryFfmpegPathname($record, $subdef_class, $this->tmpDirectory);
             }
 
             if (isset($this->tmpFilePath) && $subdef_class->getSpecs() instanceof Image) {