code: public static byte[] encodeBytesToBytes( byte[] source ) {
          byte[] encoded = null;
          try {
              encoded = encodeBytesToBytes(source, 0, source.length, Base64.NO_OPTIONS);
          } catch (IOException ex) {
              assert false : "IOExceptions only come from GZipping, which is turned off: " + ex.getMessage();
          }
          return encoded;
      }
docs: Similar to {@link #encodeBytes(byte[])} but returns a byte array instead of instantiating a String. This is more efficient
  if you're working with I/O streams and have large data sets to encode.
  
  @param source The data to convert
  @return The Base64-encoded data as a byte[] (of ASCII characters)
  @throws NullPointerException if source array is null
  @since 2.3.1