---
title: VTCompressionSession
framework: videotoolbox
role: symbol
role_heading: Class
path: videotoolbox/vtcompressionsession
---

# VTCompressionSession

A reference to a VideoToolbox compression session.

## Declaration

```swift
class VTCompressionSession
```

## Overview

Overview A compression session supports the compression of a sequence of video frames. The session is a reference-counted CoreFoundation (CF) object.

## Relationships

### Conforms To

- [Equatable](swift/equatable.md)
- [Hashable](swift/hashable.md)

## See Also

### Data Types

- [VTEncodeInfoFlags](videotoolbox/vtencodeinfoflags.md)