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# colorize(byMappingGray:to:blackMapping:whiteMapping:)

Colorizes a grayscale image.

```
func colorize(byMappingGray midPoint: CGFloat, to midPointColor: NSColor?, blackMapping shadowColor: NSColor?, whiteMapping lightColor: NSColor?)
```

## Parameters

`midPoint`

A float value representing the midpoint of the grayscale image.

`midPointColor`

A color object representing the midpoint of the color to map the image to.

`shadowColor`

A color object representing the black mapping to use for shadows.

`lightColor`

A color object representing the white mapping to be used in the image.

## Discussion

This method maps the receiver such that:

- Gray value of `midPoint` –>  `midPointColor`;
- black –> `shadowColor`;
- white –> `lightColor`.

It works on images with 8-bit SPP, and thus supports either 8-bit gray or 24-bit color (with optional alpha).

---

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