continuousAutoFocusTrackingLensPositionBias

Declaration

var continuousAutoFocusTrackingLensPositionBias: Float { get set }

Discussion

While the device is actively tracking a subject to keep in focus, this property may be used to specify a bias applied to the lens position so that different portions of the subject are in focus. This property’s default value is 0 which aims to keep the median of the subject’s depth profile in focus. Values approaching -1 bias the lens position towards the closest portion of the depth profile while values approaching 1 bias the lens position towards the furthest portion of the profile. As the subject moves, the bias continues to apply to the subject’s new depth profile.

To apply bias updates, set the device’s focus mode to AVCaptureFocusModeContinuousAutoFocus after each change. The bias value has no effect otherwise. The value will only be automatically reset to 0 if cinematic video capture is enabled.