# sampleDuration(_:) Provides the native sample duration of the object to which the effect is applied. ``` func sampleDuration(_ duration: UnsafeMutablePointer!) ``` ## Parameters `duration` The sample duration time, expressed in `CMTime`. ## Discussion Motion provides the sample duration of the project. Final Cut Pro provides the sample duration of the clip to which the effect is applied, not the sample duration for the timeline. > Note: > In Final Cut Pro, the sample duration is equal to the object’s native frame duration for progressive clips, but half of the frame duration for interlaced clips. --- 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)