code: @Override
     public byte[] getData() {
         byte[] data = new byte[frameData.length+2];
  
         int first2 = (FRAME_SYNC<<2);
         if (blockSizeVariable) first2++;
  
         IOUtils.putInt2BE(data, 0, first2);
         System.arraycopy(frameData, 0, data, 2, frameData.length);
  
         return data;
     }
docs: Returns the contents, including the sync header