diff -r 5f011170de74 -r a6cf5a06f02d server/src/app/Libraries/Transcript/TranscriptConverterBase.php
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/server/src/app/Libraries/Transcript/TranscriptConverterBase.php	Sat May 28 11:49:38 2016 +0200
@@ -0,0 +1,159 @@
+<?php
+namespace CorpusParole\Libraries\Transcript;
+
+use CorpusParole\Models\Document;
+
+use EasyRdf\Literal;
+use DateTime;
+
+
+abstract class TranscriptConverterBase implements Transcriptconverterinterface {
+
+    public function __construct(Document $document, $source, string $creationDate = null) {
+        $this->resJSON = [];
+        $this->document = $document;
+        $this->source = $source;
+        $this->creationDate = $creationDate;
+        $this->mediaRefId = null;
+        if(is_null($this->creationDate)) {
+            $this->creationDate = (new DateTime())->format(DateTime::ATOM);
+        }
+    }
+
+    public function addHeaderMeta() {
+
+        $this->resJSON['format'] = 'http://advene.org/ns/cinelab/';
+        $this->resJSON["@context"] = [
+            "dc" =>  "http://purl.org/dc/elements/1.1/",
+            "corpus" => "http://corpusdelaparole.huma-num.fr/ns/corpus#"
+        ];
+
+        $title = $this->getSourceTitle();
+        if(is_null($title)) {
+            $docTitle = $this->document->getTitle();
+            if($docTitle instanceof Literal) {
+                $titleLanguage = $docTitle->getLang();
+                $title = $titleLanguage?[$titleLanguage => $docTitle->getValue()]:$docTitle->getValue();
+            }
+            elseif(!is_null($docTitle)) {
+                $title = (string)$docTitle;
+            }
+        }
+
+        $this->title = null;
+
+        if(is_string($title)) {
+            $this->title = $title;
+        }
+        elseif(is_array($title) && count($title) == 1) {
+            $this->title = [ "@language" => key($title),  "@value" => current($title)];
+        }
+        elseif(is_array($title)) {
+            $this->title = array_reduce(array_keys($title),function($res, $k) use ($title) {
+                array_push($res, ["@language" => $k, "@value" => $title[$k]]);
+                return $res;
+            }, []);
+        }
+
+        $this->resJSON['meta'] = [
+            'dc:creator' => config('corpusparole.transcript_default_creator'),
+            'dc:contributor' => config('corpusparole.transcript_default_creator'),
+            'dc:created' => $this->creationDate,
+            'dc:modified' => $this->creationDate,
+            'dc:title' => $this->title
+        ];
+    }
+
+    // get document title
+    public function getSourceTitle() {
+        return null;
+    }
+
+    // add media
+    public function buildMedias() {
+
+        $medias = [];
+
+        $i = 1;
+        foreach($this->document->getMediaArray() as $documentMedia)
+        {
+            if(0 !== strpos($documentMedia['format'], 'audio/')) {
+                continue;
+            }
+
+            $mId = $this->document->getId()."_m$i";
+            $i++;
+            if(is_null($this->mediaRefId) || $documentMedia['master']) {
+                $this->mediaRefId = $mId;
+            }
+            array_push($medias, [
+                'id' => $mId,
+                'origin' => 0,
+                'unit' => 'ms',
+                'url' => $documentMedia['url'],
+                'meta' => [
+                    'dc:duration' => $documentMedia['extent_ms'],
+                    'dc:title' => $this->title,
+                    'dc:format' => $documentMedia['format'],
+                    'corpus:master' =>  filter_var($documentMedia['master'], FILTER_VALIDATE_BOOLEAN)
+                ]
+            ]);
+        }
+
+        return $medias;
+
+    }
+
+    public function getMediaRefId() {
+        return $this->mediaRefId;
+    }
+
+    public abstract function parseSource();
+
+    // add resources
+    public function buildResources() {
+        return [];
+    }
+
+    // add lists
+    public function buildLists() {
+        return [];
+    }
+
+    // add annotation types
+    public function buildAnnotationTypes() {
+        return [];
+    }
+
+    // add annotations
+    public abstract function buildAnnotations();
+
+    protected function buildTextvalue($text, $language) {
+        if(empty($language)) {
+            return $text;
+        } else {
+            return ['@value' => $text, '@language' => $language];
+        }
+    }
+
+    /**
+     * Convert xml to json.
+     * return an PHP array ready for serialization
+     */
+    function convertToJson() {
+
+        $this->addHeaderMeta();
+
+        $this->resJSON['medias'] = $this->buildMedias();
+
+        $this->parseSource();
+
+        $this->resJSON['resources'] = $this->buildResources();
+        $this->resJSON['lists'] = $this->buildLists();
+        $this->resJSON['annotation-types'] = $this->buildAnnotationTypes();
+        $this->resJSON['annotations'] = $this->buildAnnotations();
+
+        return $this->resJSON;
+    }
+
+}
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