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# bicubicScaleTransform()

Produces a high-quality scaled version of an image.

```
class func bicubicScaleTransform() -> any CIFilter & CIBicubicScaleTransform
```

## Return Value

The adjusted image.

## Discussion

This method applies the bicubic scale transform filter to an image. The effect produces a high-quality, scaled version of the input image. The parameters of `B` and `C` determine the sharpness and softness of the resampling.

The bicubic scale transform filter uses the following properties:

- `inputImage`: An image with the type [`CIImage`](/documentation/CoreImage/CIImage).
- `aspectRatio`: A `float` representing the aspect ratio as an <doc://com.apple.documentation/documentation/Foundation/NSNumber>.
- `parameterB`: A `float` representing the value of B used for cubic resampling as an <doc://com.apple.documentation/documentation/Foundation/NSNumber>.
- `parameterC`: A `float` representing the value of C used for cubic resampling as an <doc://com.apple.documentation/documentation/Foundation/NSNumber>.

The following code creates a filter that results in the image becoming square:

```swift
func bicubicScale(inputImage: CIImage) -> CIImage {
    let bicubicScaleFilter = CIFilter.bicubicScaleTransform()
    bicubicScaleFilter.inputImage = inputImage
    bicubicScaleFilter.aspectRatio = 0.7
    bicubicScaleFilter.parameterB = 1
    bicubicScaleFilter.parameterC = 0.75
    return bicubicScaleFilter.outputImage!
}
```

![Two photographs of a large building on the corner of an intersection. The building has small windows and is made of a brick structure. The photo on the left has no modifications to size or color. In the photo on the right, a bicubic scale transform filter is applied, resulting in a square image.](images/com.apple.coreimage/media-3582224@2x.png)

---

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