---
title: kCEAutoWidthKey
framework: Professional Video Applications
role: symbol
role_heading: Global Variable
platforms: [provideo encoder extensions 1.0+]
path: professional_video_applications/kceautowidthkey
---

# kCEAutoWidthKey

Specifies whether the output file width is set to automatic in the encoder settings.

## Declaration

```swift
var kCEAutoWidthKey: String { get }
```

## Discussion

Discussion The value of this key is a negative number if the width is set to automatic; otherwise it’s zero. When the width is set to automatic, the extension calculates the output frame width as a percentage of the source size.

## See Also

### Encoder Attribute Keys

- [kCEAllowsSegmentationKey](professional_video_applications/kceallowssegmentationkey.md)
- [kCEFileExtensionKey](professional_video_applications/kcefileextensionkey.md)
- [kCEFieldOrderKey](professional_video_applications/kcefieldorderkey.md)
- [kCEColorSpaceKey](professional_video_applications/kcecolorspacekey.md)
- [kCEAudioChannelLayoutKey](professional_video_applications/kceaudiochannellayoutkey.md)
- [kCEVideoEnabledKey](professional_video_applications/kcevideoenabledkey.md)
- [kCEAudioEnabledKey](professional_video_applications/kceaudioenabledkey.md)
- [kCEAudioSampleFloatKey](professional_video_applications/kceaudiosamplefloatkey.md)
- [kCEAudioSampleRateKey](professional_video_applications/kceaudiosampleratekey.md)
- [kCEAudioSampleSizeKey](professional_video_applications/kceaudiosamplesizekey.md)
- [kCEWidthKey](professional_video_applications/kcewidthkey.md)
- [kCEHeightKey](professional_video_applications/kceheightkey.md)
- [kCEAutoRateKey](professional_video_applications/kceautoratekey.md)
- [kCEAutoHeightKey](professional_video_applications/kceautoheightkey.md)
- [kCEPixelAspectKey](professional_video_applications/kcepixelaspectkey.md)