# frameDuration(_:) Provides the native frame duration of the object to which the effect is applied. ``` func frameDuration(_ duration: UnsafeMutablePointer!) ``` ## Parameters `duration` The frame duration time, expressed in `CMTime`. ## Discussion Motion provides the frame duration of the project. Final Cut Pro provides the frame duration of the clip to which the effect is applied, not the frame duration for the timeline. > Note: The value that the host provides is unaffected by any retiming the host may do and is always the native frame duration (before retiming) of the clip to which the effect is applied. To determine the timeline’s frame duration, divide the value from ``doc://com.apple.professionalvideoapplications/documentation/professional_video_applications/FxTimingAPI_v4/timelineFpsDenominator(for:)`` by ``doc://com.apple.professionalvideoapplications/documentation/professional_video_applications/FxTimingAPI_v4/timelineFpsNumerator(for:)`` as shown in . --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)