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# MLActionClassifier

A model you train with videos to classify a person’s body movements.

```
struct MLActionClassifier
```

## Topics

### Training an action classifier asynchronously

[`train(trainingData:parameters:sessionParameters:)`](/documentation/CreateML/MLActionClassifier/train(trainingData:parameters:sessionParameters:))

Begins an asynchronous action classifier training session.

[`makeTrainingSession(trainingData:parameters:sessionParameters:)`](/documentation/CreateML/MLActionClassifier/makeTrainingSession(trainingData:parameters:sessionParameters:))

Creates an asynchronous training session for an action classifier.

[`resume(_:)`](/documentation/CreateML/MLActionClassifier/resume(_:))

Begins or continues an asynchronous action classifier training session.

[`restoreTrainingSession(sessionParameters:)`](/documentation/CreateML/MLActionClassifier/restoreTrainingSession(sessionParameters:))

Creates an asynchronous training session for an action classifier by restoring an existing training
session’s state from its parameters.

### Creating an action classifier from a checkpoint

[`init(checkpoint:)`](/documentation/CreateML/MLActionClassifier/init(checkpoint:))

Creates an action classifier from a training session checkpoint.

### Training an action classifier synchronously

[`init(trainingData:parameters:)`](/documentation/CreateML/MLActionClassifier/init(trainingData:parameters:))

Creates an action classifier with a training dataset represented by a
data source.

### Evaluating an action classifier

[`evaluation(on:)`](/documentation/CreateML/MLActionClassifier/evaluation(on:))

Generates metrics describing the action classifier’s performance on
labeled videos represented by a data source.

[`trainingMetrics`](/documentation/CreateML/MLActionClassifier/trainingMetrics)

Measurements of the action classifier’s performance on the training dataset.

[`validationMetrics`](/documentation/CreateML/MLActionClassifier/validationMetrics)

Measurements of the action classifier’s performance on the validation dataset.

### Testing an action classifier

[`prediction(from:)`](/documentation/CreateML/MLActionClassifier/prediction(from:))

Generates a prediction for each action the classifier recognizes in the
video.

[`predictions(from:)`](/documentation/CreateML/MLActionClassifier/predictions(from:))

Generates a sequence of predictions for each video input.

[`MLActionClassifier.Prediction`](/documentation/CreateML/MLActionClassifier/Prediction)

A collection of predictions, each paired with its confidence, for a range of video frames.

### Saving an action classifier

[`write(to:metadata:)`](/documentation/CreateML/MLActionClassifier/write(to:metadata:))

Exports the action classifier as a Core ML model file to a location in
the file system.

[`write(toFile:metadata:)`](/documentation/CreateML/MLActionClassifier/write(toFile:metadata:))

Exports the action classifier as a Core ML model file to the file path.

### Inspecting an action classifier model

[`model`](/documentation/CreateML/MLActionClassifier/model)

The underlying Core ML model of the action classifier stored in memory.

[`modelParameters`](/documentation/CreateML/MLActionClassifier/modelParameters-swift.property)

The model configuration parameters the action classifier used during its training session.

### Describing an action classifier

[`description`](/documentation/CreateML/MLActionClassifier/description)

A text representation of the action classifier.

[`debugDescription`](/documentation/CreateML/MLActionClassifier/debugDescription)

A text representation of the action classifier that’s suitable for
output during debugging.

[`playgroundDescription`](/documentation/CreateML/MLActionClassifier/playgroundDescription)

A description of the action classifier shown in a playground.

### Supporting types

[`MLActionClassifier.DataSource`](/documentation/CreateML/MLActionClassifier/DataSource)

A data source for an action classifier.

[`MLActionClassifier.ModelParameters`](/documentation/CreateML/MLActionClassifier/ModelParameters-swift.struct)

Parameters that affect the training process of an action classifier.

[`MLActionClassifier.VideoAugmentationOptions`](/documentation/CreateML/MLActionClassifier/VideoAugmentationOptions)

The video augmentations for an action classifier training session.


---

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