---
title: "vImageInterpolatedLookupTable_PlanarF(_:_:_:_:_:_:_:)"
framework: accelerate
role: symbol
role_heading: Function
path: "accelerate/vimageinterpolatedlookuptable_planarf(_:_:_:_:_:_:_:)"
---

# vImageInterpolatedLookupTable_PlanarF(_:_:_:_:_:_:_:)

Uses an interpolated lookup table to transform a 32-bit planar image.

## Declaration

```swift
func vImageInterpolatedLookupTable_PlanarF(_ src: UnsafePointer<vImage_Buffer>, _ dest: UnsafePointer<vImage_Buffer>, _ table: UnsafePointer<Pixel_F>, _ tableEntries: vImagePixelCount, _ maxFloat: Float, _ minFloat: Float, _ flags: vImage_Flags) -> vImage_Error
```

## Parameters

- `src`: The source vImage buffer.
- `dest`: A pointer to the destination vImage buffer structure. You’re responsible for filling out the height, width, and rowBytes fields of this structure, and for allocating a data buffer of the appropriate size. On return, the data buffer this structure points to contains the destination image data. When you no longer need the data buffer, deallocate the memory to prevent memory leaks.
- `table`: A lookup table that contains doc://com.apple.accelerate/documentation/Accelerate/Pixel_F values.
- `tableEntries`: The number of values in the lookup table.
- `maxFloat`: A value of type float.
- `minFloat`: A value of type float.
- `flags`: The options to use when performing the operation. If your code implements its own tiling or its own multithreading, pass doc://com.apple.accelerate/documentation/Accelerate/kvImageDoNotTile.

## Return Value

Return Value kvImageNoError; otherwise, one of the error codes in Data Types and Constants.

## Discussion

Discussion Provide this function with a lookup table with any number of values, but with a minimum value of minFloat and a maximum value of maxFloat. The function generates lookup values by linearly interpolating between the supplied values. The per-pixel conversion calculation is equivalent to the following: float clippedPixel = MAX( MIN( src_pixel, maxFloat ), minFloat );    //clip src_pixel to be in range float fIndex = (float) (tableEntries - 1) * (clippedPixel - minFloat ) / (maxFloat - minFloat); float fract = fIndex - floor( fIndex ); unsigned long index =  fIndex; float result = table[ index ] * ( 1.0f - fract ) + table[ index + 1] * fract; The following code shows a lookup table that contains two values, 1 and 0. The result is that the lookup transformation maps the source values 0...1 to the destination values 1...0. let lookupTable: [Float] = [1, 0]

let source = vImage.PixelBuffer<vImage.PlanarF>(     pixelValues: [0.2, 0.4, 0.6, 0.8],     size: .init(width: 4, height: 1))

let destination = vImage.PixelBuffer<vImage.PlanarF>(     size: source.size)

source.withUnsafePointerToVImageBuffer{ src in     destination.withUnsafePointerToVImageBuffer { dest in                  _ = vImageInterpolatedLookupTable_PlanarF(             src,             dest,             lookupTable,             vImagePixelCount(lookupTable.count),             1, 0,             vImage_Flags(kvImageNoFlags))     } }

// Prints "[0.8, 0.6, 0.4, 0.2]". print(destination.array)

## See Also

### Transforming planar-to-planar with a lookup table

- [vImageTableLookUp_Planar8(_:_:_:_:)](accelerate/vimagetablelookup_planar8(_:_:_:_:).md)
- [vImageLookupTable_PlanarFtoPlanar8(_:_:_:_:)](accelerate/vimagelookuptable_planarftoplanar8(_:_:_:_:).md)
- [vImageLookupTable_Planar8toPlanar16(_:_:_:_:)](accelerate/vimagelookuptable_planar8toplanar16(_:_:_:_:).md)
- [vImageLookupTable_Planar8toPlanarF(_:_:_:_:)](accelerate/vimagelookuptable_planar8toplanarf(_:_:_:_:).md)
- [vImageLookupTable_8to64U(_:_:_:_:)](accelerate/vimagelookuptable_8to64u(_:_:_:_:).md)
- [vImageLookupTable_Planar16(_:_:_:_:)](accelerate/vimagelookuptable_planar16(_:_:_:_:).md)