<?php
  require_once('jpgraph/datamatrix/datamatrix.inc.php');
  
  $data = 'This is a 20x20 symbol';
  
  // Create and set parameters for the encoder
  $encoder = DatamatrixFactory::Create(DMAT_20x20);
  $encoder->SetEncoding(ENCODING_TEXT);
  
  // Create the image backend (default)
  $backend = DatamatrixBackendFactory::Create($encoder);
  
  // By default the module width is 2 pixel so we increase it a bit
  $backend->SetModuleWidth(4);
  
  // Set Quiet zone
  $backend->SetQuietZone(10);
  
  // Set other than default colors (one, zero, quiet zone/background)
  $backend->SetColor('navy','white','lightgray');
  
  // Create the barcode from the given data string and write to output file
  try {
      $backend->Stroke($data);
  } catch (Exception $e) {
      $errstr = $e->GetMessage();
      echo "Datamatrix error message: $errstr\n";
  }
  
  ?>