Calculating Hamming distance of a byte array with number of bits set with Scala

hammingDistance.scala

object HammingDistance {
  def main(args: Array[String]) = {
    val b1 : Array[Byte] = Array(5, 7) // 0b00000101, 0b00000111
    val b2 : Array[Byte] = Array(6, 8) // 0b00000110, 0b00001000
    println(hammingDistance(b1, b2)) // Output: 6
  }

  // Calculate a sum of set bits of XOR'ed bytes
  def hammingDistance(b1: Array[Byte], b2: Array[Byte]) = {
    (b1.zip(b2).map((x: (Byte, Byte)) => numberOfBitsSet((x._1 ^ x._2).toByte))).sum
  }

  // 1 iteration for each bit, 8 total. Shift right and AND 1 to get i-th bit
  def numberOfBitsSet(b: Byte) : Int = (0 to 7).map((i : Int) => (b >>> i) & 1).sum
}