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# convertLabToRGB()

Converts an image from CIELAB to RGB color space.

```
class func convertLabToRGB() -> any CIFilter & CIConvertLab
```

## Return Value

The converted [`CIImage`](/documentation/CoreImage/CIImage).

## Discussion

This filter converts an image from CIELAB color space to RGB. The CIELAB color space expresses color as three values: L* for the perceptual lightness, and a*b* for the colors red, green, blue, and yellow. The RGB color space expresses colors using the intensities of the three primary colors: red, green, and blue.

- `inputImage`: A [`CIImage`](/documentation/CoreImage/CIImage) containing the `RGB` image.
- `normalize`: If true, the three input channels are in the range 0 to 1. If false, the L* channel is in the range 0 to 100, and the a*b* channels are in the range -128 to 128.

The following code applies the `convertLabToRGBFilter` to an image with the `normalize` flag set to the `true`:

```swift
func convertLabToRGB(inputImage: CIImage) -> CIImage {
    let filter = CIFilter.convertLabToRGB()
    filter.inputImage = inputImage
    filter.normalize = true
    return filter.outputImage!
}
```

![Two images arranged horizontally. The left image contains a photo of the Golden Gate Bridge with a clear sky as the background. It has been transformed into the Lab color space. The bridge is a light cyan color and the sky is a gradient from yellow-green through to red-pink.  The right image shows the result of applying the convert-RGB-to-Lab to this image. The bridge is a red color and sky is gradient going from light blue at the horizon to dark blue at the top of the image.](images/com.apple.coreimage/media-4407298@2x.png)

---

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