---
title: "vImageGetResamplingFilterExtent(_:_:)"
framework: accelerate
role: symbol
role_heading: Function
path: "accelerate/vimagegetresamplingfilterextent(_:_:)"
---

# vImageGetResamplingFilterExtent(_:_:)

Returns the maximum sampling radius for a resampling filter.

## Declaration

```swift
func vImageGetResamplingFilterExtent(_ filter: ResamplingFilter, _ flags: vImage_Flags) -> vImagePixelCount
```

## Parameters

- `filter`: The resampling filter to query.
- `flags`: The flags you intend to pass to the horizontal or vertical shear function.

## Return Value

Return Value The maximum sampling radius for the specified resampling filter.

## Discussion

Discussion This function returns the maximum distance from any pixel that the filter will look, either horizontally or vertically, depending on whether a horizontal or vertical shear is used.  It’s analogous to kernelWidth in vImageNewResamplingFilterForFunctionUsingBuffer(_:_:_:_:_:_:), but might be slightly larger to allow for extra slope when dealing with subpixel coordinates during resampling.

## See Also

### Resampling filters

- [vImageNewResamplingFilter(_:_:)](accelerate/vimagenewresamplingfilter(_:_:).md)
- [vImageNewResamplingFilterForFunctionUsingBuffer(_:_:_:_:_:_:)](accelerate/vimagenewresamplingfilterforfunctionusingbuffer(_:_:_:_:_:_:).md)
- [vImageGetResamplingFilterSize(_:_:_:_:)](accelerate/vimagegetresamplingfiltersize(_:_:_:_:).md)
- [vImageDestroyResamplingFilter(_:)](accelerate/vimagedestroyresamplingfilter(_:).md)