# FxTimingAPI_v4 A protocol that defines the methods provided by the host, so that a plug-in can query the timing properties of its input. ``` protocol FxTimingAPI_v4 ``` ## Overview Using the FxTimingAPI, your plug-in can query the timing properties of its input image or images, image parameters, effect, timeline, and in or out points. > Note: > This version of the API is only available to plug-ins built in the FxPlug 4 style and later, and it intentionally doesn’t inherit from previous versions. ## Topics ### Accessing Timing Values [`func frameDuration(UnsafeMutablePointer!)`](/documentation/professional_video_applications/FxTimingAPI_v4/frameDuration(_:)) Provides the native frame duration of the object to which the effect is applied. [`func sampleDuration(UnsafeMutablePointer!)`](/documentation/professional_video_applications/FxTimingAPI_v4/sampleDuration(_:)) Provides the native sample duration of the object to which the effect is applied. [`func startTime(forEffect: UnsafeMutablePointer!)`](/documentation/professional_video_applications/FxTimingAPI_v4/startTime(forEffect:)) Provides the start time for the effect. [`func durationTime(forEffect: UnsafeMutablePointer!)`](/documentation/professional_video_applications/FxTimingAPI_v4/durationTime(forEffect:)) Provides the duration time for the effect. [`func startTimeOfInput(toFilter: UnsafeMutablePointer!)`](/documentation/professional_video_applications/FxTimingAPI_v4/startTimeOfInput(toFilter:)) Provides the start time of the filter’s image input clip. [`func durationTimeOfInput(toFilter: UnsafeMutablePointer!)`](/documentation/professional_video_applications/FxTimingAPI_v4/durationTimeOfInput(toFilter:)) Provides the duration of the filter’s image input clip. [`func start(UnsafeMutablePointer!, ofImageParameter: UInt32)`](/documentation/professional_video_applications/FxTimingAPI_v4/start(_:ofImageParameter:)) Provides the start time of the clip the user assigned to the given image parameter for the effect. [`func durationTime(UnsafeMutablePointer!, ofImageParameter: UInt32)`](/documentation/professional_video_applications/FxTimingAPI_v4/durationTime(_:ofImageParameter:)) Provides the duration of the clip the user assigns to the given image parameter for the effect. [`func inPointTimeOfTimeline(forEffect: UnsafeMutablePointer!)`](/documentation/professional_video_applications/FxTimingAPI_v4/inPointTimeOfTimeline(forEffect:)) The in point of the timeline on which the user applies the effect. [`func outPointTimeOfTimeline(forEffect: UnsafeMutablePointer!)`](/documentation/professional_video_applications/FxTimingAPI_v4/outPointTimeOfTimeline(forEffect:)) The out point of the timeline on which the user applies the effect. [`func timelineTime(UnsafeMutablePointer!, fromInputTime: CMTime)`](/documentation/professional_video_applications/FxTimingAPI_v4/timelineTime(_:fromInputTime:)) Converts from input time of the filter’s image input to timeline time. [`func timelineTime(UnsafeMutablePointer!, fromImageTime: CMTime, forParameterID: UInt32)`](/documentation/professional_video_applications/FxTimingAPI_v4/timelineTime(_:fromImageTime:forParameterID:)) Converts from image time of the given parameter to timeline time. [`func inputTime(UnsafeMutablePointer!, fromTimelineTime: CMTime)`](/documentation/professional_video_applications/FxTimingAPI_v4/inputTime(_:fromTimelineTime:)) Converts from timeline time to time of the filter’s image input. [`func imageTime(UnsafeMutablePointer!, forParameterID: UInt32, fromTimelineTime: CMTime)`](/documentation/professional_video_applications/FxTimingAPI_v4/imageTime(_:forParameterID:fromTimelineTime:)) Converts from timeline time of the given parameter to image time. [`func fieldOrderForInput(toFilter: (any FxTileableEffect)!) -> FxFieldOrder`](/documentation/professional_video_applications/FxTimingAPI_v4/fieldOrderForInput(toFilter:)) Returns the field order of the filter input. [`func timelineFpsNumerator(for: (any FxTileableEffect)!) -> Int`](/documentation/professional_video_applications/FxTimingAPI_v4/timelineFpsNumerator(for:)) The numerator of the timeline’s frame rate where the user applies the effect. [`func timelineFpsDenominator(for: (any FxTileableEffect)!) -> Int`](/documentation/professional_video_applications/FxTimingAPI_v4/timelineFpsDenominator(for:)) The denominator of the timeline’s frame rate where the user applies the effect. --- 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)