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# kVTPixelTransferPropertyKey_ScalingMode

Scaling mode for images during transfer between source and destination buffers.

```
let kVTPixelTransferPropertyKey_ScalingMode: CFString
```

## Discussion

Depending on the scaling mode, scaling may take into account:

- The full image buffer width and height of the source and destination
- The clean aperture attachment (<doc://com.apple.documentation/documentation/CoreVideo/kCVImageBufferCleanApertureKey>) on the source image buffer
- The pixel aspect ratio attachment (<doc://com.apple.documentation/documentation/CoreVideo/kCVImageBufferPixelAspectRatioKey>) on the source image buffer
- The destination clean aperture ([`kVTPixelTransferPropertyKey_DestinationCleanAperture`](/documentation/VideoToolbox/kVTPixelTransferPropertyKey_DestinationCleanAperture))
- The destination pixel aspect ratio ([`kVTPixelTransferPropertyKey_DestinationPixelAspectRatio`](/documentation/VideoToolbox/kVTPixelTransferPropertyKey_DestinationPixelAspectRatio))

The destination image buffer’s clean aperture and pixel aspect ratio attachments are not taken into account, and are overwritten.

---

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