private static ASInputStream getLookup(COSObject object) {
   COSObjType type = object.getType();
   if (type == COSObjType.COS_STRING) {
     return new ASMemoryInStream(object.getString().getBytes());
   } else if (type == COSObjType.COS_STREAM) {
     return object.getData(COSStream.FilterFlags.DECODE);
   } else {
     if (!object.empty()) {
       LOGGER.debug("Unknown lookup type");
     }
     return null;
   }
 }