/**
  * Decode the datas, depending on the transfer syntax
  * 
  * @param CDicomStreamReader $stream_reader   The stream writer
  * 
  * @param string             $transfer_syntax The UID of the transfer syntax
  * 
  * @return void
  */
 function decode(CDicomStreamReader $stream_reader, $transfer_syntax)
 {
     if (!$transfer_syntax) {
         return;
     }
     $this->attributes = array();
     $this->datasets = array();
     $stream_length = $stream_reader->getStreamLength();
     while ($stream_reader->getPos() < $stream_length) {
         $dataset = new CDicomDataSet();
         $dataset->decode($stream_reader, $transfer_syntax);
         $group = $dataset->getGroupNumber();
         $element = $dataset->getElementNumber();
         if (!array_key_exists($group, $this->datasets)) {
             $this->datasets[$group] = array();
         }
         if (!array_key_exists($group, $this->attributes)) {
             $this->attributes[$group] = array();
         }
         $this->datasets[$group][$element] = $dataset;
         $this->attributes[$group][$element] = $dataset->getValue();
     }
 }
 /**
  * Decode the PDU
  * 
  * @param CDicomStreamReader $stream_reader The stream reader
  *  
  * @return null
  */
 function decodePDU(CDicomStreamReader $stream_reader)
 {
     $this->pdvs = array();
     $stream_reader->setStreamLength($this->getTotalLength());
     while ($stream_reader->getPos() < $stream_reader->getStreamLength()) {
         $pdv_length = $stream_reader->readUInt32();
         // + 4;
         //$stream_reader->seek(-4);
         $pdv_content = $stream_reader->read($pdv_length);
         $pdv_handle = fopen('php://temp', 'w+');
         fwrite($pdv_handle, $pdv_content, $pdv_length);
         $pdv_stream = new CDicomStreamReader($pdv_handle);
         $pdv_stream->rewind();
         $pdv = new CDicomPDV(array("presentation_contexts" => $this->presentation_contexts, "length" => $pdv_length));
         $pdv->decode($pdv_stream);
         $this->pdvs[] = $pdv;
     }
 }