# init(source:range:timescale:) Creates a temporal-segment identifier. ``` init(source: String, range: Range, timescale: Int) ``` ## Parameters `source` A unique source description. `range` A timestamp range. `timescale` The number of uniquely identifiable timestamps in a second. --- 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)