static BitMatrix randomBitMatrix(int w, int h, optional Random random) {
  int[] data = arrayOfRandomInts(IntArrayBitMatrix.arrayLength(w, h), random);
  ret new IntArrayBitMatrix(w, h, data);
}

static BitMatrix randomBitMatrix(int w, int h, double probability) {
  int[] data = arrayOfRandomBitsAsInts(w*h, probability);
  ret new IntArrayBitMatrix(w, h, data);
}