---
title: "cleanAperture(originIsAtTopLeft:)"
framework: coremedia
role: symbol
role_heading: Instance Method
path: "coremedia/cmformatdescription/cleanaperture(originisattopleft:)"
---

# cleanAperture(originIsAtTopLeft:)

Returns the clean aperture.

## Declaration

```swift
func cleanAperture(originIsAtTopLeft: Bool) -> CGRect
```

## Parameters

- `originIsAtTopLeft`: If true, the origin begins at the top-left corner of the rectangle instead of the bottom-left.

## See Also

### Working with Video Descriptions

- [matchesImageBuffer(_:)](coremedia/cmformatdescription/matchesimagebuffer(_:).md)
- [presentationDimensions(usePixelAspectRatio:useCleanAperture:)](coremedia/cmformatdescription/presentationdimensions(usepixelaspectratio:usecleanaperture:).md)