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# AVPlaybackUserInterfaceTimelineSegment

Represents a contiguous segment of timeline content with specific playback characteristics.

```
class AVPlaybackUserInterfaceTimelineSegment
```

## Overview

Timeline segments divide media content into distinct regions, each with its own classification
and behavior rules. Segments are typically used to distinguish between primary content and
auxiliary content such as advertisements or bonus material, and to control whether users can
seek or skip through specific portions of the timeline.

## Topics

### Initializers

[`init?(coder: NSCoder)`](/documentation/AVKit/AVPlaybackUserInterfaceTimelineSegment/init(coder:))

[`init(timeRange: CMTimeRange, segmentType: AVPlaybackUserInterfaceTimelineSegmentType, marked: Bool, requiresLinearPlayback: Bool, identifier: String?)`](/documentation/AVKit/AVPlaybackUserInterfaceTimelineSegment/init(timeRange:segmentType:marked:requiresLinearPlayback:identifier:))

Initializes a new timeline segment with the specified characteristics.

### Instance Properties

[`var identifier: String?`](/documentation/AVKit/AVPlaybackUserInterfaceTimelineSegment/identifier)

Optional external identifier for tracking or analytics purposes. May correspond to advertisement IDs, chapter markers, or other external systems.

[`var isMarked: Bool`](/documentation/AVKit/AVPlaybackUserInterfaceTimelineSegment/isMarked)

Indicates whether this segment should be visually highlighted or marked in the timeline UI.

[`var requiresLinearPlayback: Bool`](/documentation/AVKit/AVPlaybackUserInterfaceTimelineSegment/requiresLinearPlayback)

Indicates whether this segment must be played sequentially without seeking or skipping. Typically used for advertisements or important announcements.

[`var segmentType: AVPlaybackUserInterfaceTimelineSegmentType`](/documentation/AVKit/AVPlaybackUserInterfaceTimelineSegment/segmentType)

The type of content within this segment, indicating whether it is primary program content or a specific category of auxiliary content.

[`var timeRange: CMTimeRange`](/documentation/AVKit/AVPlaybackUserInterfaceTimelineSegment/timeRange)

The time range defining the segment’s position and duration within the overall timeline.

## Relationships

### Conforms To

[`NSCoding`](/documentation/Foundation/NSCoding)

[`Sendable`](/documentation/Swift/Sendable)

[`NSCopying`](/documentation/Foundation/NSCopying)

[`NSSecureCoding`](/documentation/Foundation/NSSecureCoding)

[`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol)

[`Hashable`](/documentation/Swift/Hashable)

[`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible)

[`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible)

[`Equatable`](/documentation/Swift/Equatable)

[`CVarArg`](/documentation/Swift/CVarArg)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

### Inherits From

[`NSObject-swift.class`](/documentation/ObjectiveC/NSObject-swift.class)

---

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