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# CMSampleDataReference

References sample data in at a URL.

```
struct CMSampleDataReference
```

## Overview

The size of the data is provided as [`totalSampleSize`](/documentation/CoreMedia/CMReadySampleBuffer/totalSampleSize).

## Topics

### Initializers

[`init(containerLocation: URL, byteOffset: Int)`](/documentation/CoreMedia/CMSampleDataReference/init(containerLocation:byteOffset:))

### Instance Properties

[`var byteOffset: Int`](/documentation/CoreMedia/CMSampleDataReference/byteOffset)

Offset of the sample data in the container.

[`var containerLocation: URL`](/documentation/CoreMedia/CMSampleDataReference/containerLocation)

Container of the sample data.

## Relationships

### Conforms To

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

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

[`MultiSampleContent`](/documentation/CoreMedia/CMSampleBuffer/MultiSampleContent)

[`ContentWithFormatDescription`](/documentation/CoreMedia/CMSampleBuffer/ContentWithFormatDescription)

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

[`Content`](/documentation/CoreMedia/CMSampleBuffer/Content)

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

---

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