# PlaybackDataset

Source: https://www.nianticspatial.com/docs/api/swift/NSDK.class-PlaybackDataset/

PlaybackDataset

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## Declaration

class PlaybackDataset

## Summary

A dataset loaded from a capture JSON file containing frame metadata.
This class uses on-demand loading for frame images and depth data.
Only the currently requested frame is loaded into memory, reducing memory pressure
for large datasets.

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## Properties

| Name | Type | Summary |
| --- | --- | --- |
| let captureRoot | CaptureRoot | The fully decoded `capture.json` for this dataset (capture-level metadata plusper-frame metadata, including each frame's recorded GPS `location`). Exposed socallers can read the recording's metadata -- e.g. its location -- without running playback. |
| let compassTimestampBase | ClockBase | Clock this dataset's compass `headingTimestamp` values are on. Uses the explicit`compassTimestampBase` field when present, otherwise classifies by the first non-zeroheading timestamp's magnitude (zero timestamps mean "not captured" and are skipped).Resolved once at load, like the other SDKs. |

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## Methods

| Name | Type | Summary |
| --- | --- | --- |
| hasDepth | Bool | Checks if the dataset has depth data from a LiDAR source. |

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## Nested Types

### Structs

| Name | Type | Summary |
| --- | --- | --- |
| CaptureMetadata | CaptureMetadata | Metadata structure for capture information. All fields optional so varying capture exports decode without keyNotFound. |
| CaptureRoot | CaptureRoot | Root structure for the capture JSON file. Required fields per capture.json spec; optional fields may be omitted. |
| FrameMetadata | FrameMetadata | Frame metadata structure matching the JSON format. Required fields per capture.json spec; optional fields may be omitted. |
| LocationMetadata | LocationMetadata | Location metadata structure. All fields are optional so various capture formats (2D-only GPS, no compass, minimal logs) decode without keyNotFound. |

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### Enums

| Name | Type | Summary |
| --- | --- | --- |
| PlaybackDatasetError | PlaybackDatasetError | Errors that can occur when retrieving frame data. |

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