---
title: CMIOExtensionStreamFormat
framework: coremediaio
role: symbol
role_heading: Class
path: coremediaio/cmioextensionstreamformat
---

# CMIOExtensionStreamFormat

An object that describes the format of a media stream.

## Declaration

```swift
class CMIOExtensionStreamFormat
```

## Topics

### Creating a Stream Format

- [init(formatDescription:maxFrameDuration:minFrameDuration:validFrameDurations:)](coremediaio/cmioextensionstreamformat/init(formatdescription:maxframeduration:minframeduration:validframedurations:).md)

### Configuring Frame Durations

- [minFrameDuration](coremediaio/cmioextensionstreamformat/minframeduration.md)
- [maxFrameDuration](coremediaio/cmioextensionstreamformat/maxframeduration.md)
- [validFrameDurations](coremediaio/cmioextensionstreamformat/validframedurations-707st.md)

### Accessing the Format Description

- [formatDescription](coremediaio/cmioextensionstreamformat/formatdescription.md)

### Initializers

- [init(coder:)](coremediaio/cmioextensionstreamformat/init(coder:).md)

## Relationships

### Inherits From

- [NSObject](objectivec/nsobject-swift.class.md)

### Conforms To

- [CVarArg](swift/cvararg.md)
- [CustomDebugStringConvertible](swift/customdebugstringconvertible.md)
- [CustomStringConvertible](swift/customstringconvertible.md)
- [Equatable](swift/equatable.md)
- [Hashable](swift/hashable.md)
- [NSCoding](foundation/nscoding.md)
- [NSCopying](foundation/nscopying.md)
- [NSObjectProtocol](objectivec/nsobjectprotocol.md)
- [NSSecureCoding](foundation/nssecurecoding.md)

## See Also

### Accessing the Source Format

- [formats](coremediaio/cmioextensionstreamsource/formats.md)