code: public static long[] unshuffleLongArray(byte[] input) throws IOException {
          long[] output = new long[input.length / 8];
          int numProcessed = impl.unshuffle(input, 0, 8, input.length, output, 0);
          assert(numProcessed == input.length);
          return output;
      }
docs: Convert the input bit-shuffled byte array into an original long array.
  
  @param input
  @return a long array
  @throws IOException