---
title: opticalFlow
framework: videotoolbox
role: symbol
role_heading: Instance Property
path: videotoolbox/vtsuperresolutionscalerparameters/opticalflow
---

# opticalFlow

Optional object that contains forward and backward optical flow with the previous frame.

## Declaration

```swift
var opticalFlow: VTFrameProcessorOpticalFlow? { get }
```

## Discussion

Discussion You only need this if optical flow is pre-computed. For the first frame this is nil.

## See Also

### Inspecting the parameters

- [sourceFrame](videotoolbox/vtsuperresolutionscalerparameters/sourceframe.md)
- [previousFrame](videotoolbox/vtsuperresolutionscalerparameters/previousframe.md)
- [previousOutputFrame](videotoolbox/vtsuperresolutionscalerparameters/previousoutputframe.md)
- [submissionMode](videotoolbox/vtsuperresolutionscalerparameters/submissionmode-swift.property.md)
- [VTSuperResolutionScalerParameters.SubmissionMode](videotoolbox/vtsuperresolutionscalerparameters/submissionmode-swift.enum.md)