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# kCMFormatDescriptionCameraCalibration_ExtrinsicOriginSource

```
let kCMFormatDescriptionCameraCalibration_ExtrinsicOriginSource: CFString
```

## Discussion

\abstract Identifies how the origin of the camera system’s extrinsics are determined.
\discussion The ‘blin’ value indicates the center of transform is determined by the point mid way along the dimensions indicated by the StereoCameraSystemBaselineBox held in the StereoCameraSystemBox.
Each left and right lens within a stereoscopic camera system is equidistant from this point, so the ‘blin’ value is halved when associated with the respective left and right lenses.

---

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