code: public static void writeToStream(BitMatrix matrix, String format, OutputStream stream) throws IOException {
      writeToStream(matrix, format, stream, DEFAULT_CONFIG);
    }
docs: Writes a {@link BitMatrix} to a stream with default configuration.
  
  @param matrix {@link BitMatrix} to write
  @param format image format
  @param stream {@link OutputStream} to write image to
  @throws IOException if writes to the stream fail
  @see #toBufferedImage(BitMatrix)