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# vDSP.DCTTransformType

An enumeration that describes the discrete cosine transform types.

```
enum DCTTransformType
```

## Topics

### Discrete Cosine Transform Type Constants

[`case II`](/documentation/Accelerate/vDSP/DCTTransformType/II)

A constant that represents a type-II discrete cosine transform.

[`case III`](/documentation/Accelerate/vDSP/DCTTransformType/III)

A constant that represents a type-III discrete cosine transform.

[`case IV`](/documentation/Accelerate/vDSP/DCTTransformType/IV)

A constant that represents a type-IV discrete cosine transform.

### Instance Properties

[`var dctType: vDSP_DCT_Type`](/documentation/Accelerate/vDSP/DCTTransformType/dctType)

The vDSP DCT type of this value.

## Relationships

### Conforms To

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

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

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

---

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