# keyframe(_:atOrBefore:fromParameter:andChannel:) Returns the info about the nearest previous keyframe. ``` func keyframe(_ keyframe: UnsafeMutablePointer, atOrBefore time: CMTime, fromParameter parameterID: Int, andChannel channelIndex: Int) -> (any Error)? ``` ## Parameters `keyframe` A pointer to a struct which will receive information about the keyframe at or before the given time. `time` The time () you want a keyframe at or before. `parameterID` The ID of the parameter for which you want the keyframe information. `channelIndex` The index of the channel of the parameter for which you want the keyframe information. --- 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)