---
title: MPSNNLossCallback
framework: metalperformanceshaders
role: symbol
role_heading: Protocol
path: metalperformanceshaders/mpsnnlosscallback
---

# MPSNNLossCallback

## Declaration

```swift
protocol MPSNNLossCallback : NSCopying, NSSecureCoding, NSObjectProtocol
```

## Topics

### Instance Methods

- [scalarWeight(forSourceImage:destinationImage:)](metalperformanceshaders/mpsnnlosscallback/scalarweight(forsourceimage:destinationimage:).md)

## Relationships

### Inherits From

- [NSCoding](foundation/nscoding.md)
- [NSCopying](foundation/nscopying.md)
- [NSObjectProtocol](objectivec/nsobjectprotocol.md)
- [NSSecureCoding](foundation/nssecurecoding.md)