Deploying CNN to iOS

You need to drag-and-drop the Core ML file generated in the previous section into your project to start working with the model.

Imports:

import Foundation
import Vision
import AVFoundation
import UIKit

At first, let's define some data structures. An enumeration for possible classification results:

enum FaceExpressions: String {
 case angry = "angry"
 case anxious = "anxious"
 case neutral = "neutral"
 case happy = "happy"
 case sad = "sad"
}

An enum for errors of the classifier:

enum ClassifierError: Error {
 case unableToResizeBuffer
 case noResults
}

Classifier is a wrapper singleton for Core ML model:

class Classifier {
 public static let shared = Classifier()
 
 private let visionModel: VNCoreMLModel
 var visionRequests = [VNRequest]()
 var completion: ((_ label: [(FaceExpressions, Double)], _ error: Error?)->(...