VT_NUM_BITS = 8,
    VT_NARROW_RANGE = 10
  };
  float min() const {
    return GetField<float>(VT_MIN, 0.0f);
  }
  float max() const {
    return GetField<float>(VT_MAX, 0.0f);
  }
  int32_t num_bits() const {
    return GetField<int32_t>(VT_NUM_BITS, 0);
  }
  bool narrow_range() const {
    return GetField<uint8_t>(VT_NARROW_RANGE, 0) != 0;
  }