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# Field Detail Extension Constants

Constants that identify field detail extensions.

## Topics

### Constants

[`let kCMFormatDescriptionFieldDetail_SpatialFirstLineEarly: CFString`](/documentation/CoreMedia/kCMFormatDescriptionFieldDetail_SpatialFirstLineEarly-swift.var)

[`let kCMFormatDescriptionFieldDetail_SpatialFirstLineLate: CFString`](/documentation/CoreMedia/kCMFormatDescriptionFieldDetail_SpatialFirstLineLate-swift.var)

[`let kCMFormatDescriptionFieldDetail_TemporalTopFirst: CFString`](/documentation/CoreMedia/kCMFormatDescriptionFieldDetail_TemporalTopFirst-swift.var)

[`let kCMFormatDescriptionFieldDetail_TemporalBottomFirst: CFString`](/documentation/CoreMedia/kCMFormatDescriptionFieldDetail_TemporalBottomFirst-swift.var)


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