---
title: FxCustomParameterInterpolation_v2
framework: Professional Video Applications
role: symbol
role_heading: Protocol
platforms: [fxplug 4.0+]
path: professional_video_applications/fxcustomparameterinterpolation_v2
---

# FxCustomParameterInterpolation_v2

Defines the methods a plug-in needs to implement to support keyframing custom parameters.

## Declaration

```swift
protocol FxCustomParameterInterpolation_v2
```

## Overview

Overview An FxPlug 4 or later plug-in that wants to support keyframing custom parameters must conform to the FxCustomParameterInterpolation_v2 or later protocol. This protocol allows the plug-in to generate interpolated (in-between) values between keyframes. Note that this protocol intentionally does not inherit from the FxCustomParameterInterpolation protocol, which is for older-style plug-ins.

## Topics

### Instance Methods

- [interpolateBetween(_:withWeight:)](professional_video_applications/fxcustomparameterinterpolation_v2/interpolatebetween(_:withweight:).md)
- [isEqual(_:)](professional_video_applications/fxcustomparameterinterpolation_v2/isequal(_:).md)

## See Also

### Custom Parameter APIs

- [FxCustomParameterViewHost_v2](professional_video_applications/fxcustomparameterviewhost_v2.md)
- [FxCustomParameterActionAPI_v4](professional_video_applications/fxcustomparameteractionapi_v4.md)