---
title: VNHumanBodyPose3DObservation.HeightEstimation.reference
framework: vision
role: symbol
role_heading: Case
path: vision/vnhumanbodypose3dobservation/heightestimation-swift.enum/reference
---

# VNHumanBodyPose3DObservation.HeightEstimation.reference

A technique that uses a reference height.

## Declaration

```swift
case reference
```

## Discussion

Discussion If there’s no depth data available, the framework uses a reference height of 1.8 meters.

## See Also

### Techniques

- [VNHumanBodyPose3DObservation.HeightEstimation.measured](vision/vnhumanbodypose3dobservation/heightestimation-swift.enum/measured.md)
- [VNHumanBodyPose3DObservation.HeightEstimation.measured](vision/vnhumanbodypose3dobservation/heightestimation-swift.enum/measured.md)