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# kCVImageBufferDisplayMaskRectangleKey

Specifies the rectangular display area within the image.

```
let kCVImageBufferDisplayMaskRectangleKey: CFString
```

## Discussion

Specify the left, width, top, and height metrics relative to a reference raster width and height scaled to the image buffer dimensions.

The value is a dictionary containing these keys for the raster rectangle:

- [`kCVImageBufferDisplayMaskRectangle_ReferenceRasterWidthKey`](/documentation/CoreVideo/kCVImageBufferDisplayMaskRectangle_ReferenceRasterWidthKey)
- [`kCVImageBufferDisplayMaskRectangle_ReferenceRasterHeightKey`](/documentation/CoreVideo/kCVImageBufferDisplayMaskRectangle_ReferenceRasterHeightKey)
- [`kCVImageBufferDisplayMaskRectangle_RectangleLeftKey`](/documentation/CoreVideo/kCVImageBufferDisplayMaskRectangle_RectangleLeftKey)
- [`kCVImageBufferDisplayMaskRectangle_RectangleWidthKey`](/documentation/CoreVideo/kCVImageBufferDisplayMaskRectangle_RectangleWidthKey)
- [`kCVImageBufferDisplayMaskRectangle_RectangleTopKey`](/documentation/CoreVideo/kCVImageBufferDisplayMaskRectangle_RectangleTopKey)
- [`kCVImageBufferDisplayMaskRectangle_RectangleHeightKey`](/documentation/CoreVideo/kCVImageBufferDisplayMaskRectangle_RectangleHeightKey)

---

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