A time value that acts as a modifier to a capture device’s
- iOS 13.0+
- Mac Catalyst 13.0+
A capture device’s
active property is the reciprocal of its active maximum frame rate. To limit the maximum frame rate of the capture device, you may set
active to a value supported by the device’s
active. Changes you make to the device’s
active value take effect immediately without disrupting preview. Therefore,
AVCapture must always allocate sufficient resources to allow the device to run at its active format’s maximum frame rate.
If you wish to use a particular device format but run it only at lower frame rates (for instance, only run a 1080p240 fps format at a maximum frame rate of 60), set the input's
video property to the reciprocal of the maximum frame rate you intend to use before starting the session (or within a
commit block while running the session).
This property’s default value is
invalid. When you remove a device input from a session and then add it back, this property reverts to its default value.