---
title: "outputFormat(at:arguments:)"
framework: coreimage
role: symbol
role_heading: Type Method
path: "coreimage/ciimageprocessorkernel/outputformat(at:arguments:)"
---

# outputFormat(at:arguments:)

Override this class method if your processor has more than one output and you want your processor’s output to be in a specific supported CIPixelFormat.

## Declaration

```swift
class func outputFormat(at outputIndex: Int32, arguments: [String : Any]?) -> CIFormat
```

## Parameters

- `outputIndex`: The index that tells you which processor output for which to return the desired CIPixelFormat
- `arguments`: The arguments dictionary that was passed to doc://com.apple.coreimage/documentation/CoreImage/CIImageProcessorKernel/apply(withExtent:inputs:arguments:).

## Return Value

Return Value  Return the desired CIPixelFormat

## Discussion

Discussion The format must be one of kCIFormatBGRA8, kCIFormatRGBAh, kCIFormatRGBAf or kCIFormatR8. On iOS 12 and macOS 10.14, the formats kCIFormatRh and kCIFormatRf are also supported. If the outputFormat is 0, then the output will be a supported format that best matches the rendering context’s /CIContext/workingFormat.