feat: add no light challenge implementation (#127)

* feat: add no light challenge implementation

* update package.swift for CI build

* Fix unit tests

* Address review comments

Author: thisisabhash

HostApp/HostApp.xcodeproj/project.pbxproj

@@ -308,8 +308,6 @@
 				Base,
 			);
 			mainGroup = 9070FF97285112B4009867D5;
-			packageReferences = (
-			);
 			productRefGroup = 9070FFA1285112B4009867D5 /* Products */;
 			projectDirPath = "";
 			projectRoot = "";

HostApp/HostApp.xcodeproj/project.xcworkspace/xcshareddata/swiftpm/Package.resolved

@@ -22,7 +22,8 @@ struct ExampleLivenessView: View {
         case .liveness:
             FaceLivenessDetectorView(
                 sessionID: viewModel.sessionID,
-                region: "us-east-1",
+                // TODO: Change before merging to main
+                region: "us-west-2",
                 isPresented:  Binding(
                     get: { viewModel.presentationState == .liveness },
                     set: { _ in }

HostApp/HostApp/Views/ExampleLivenessView.swift

@@ -13,7 +13,8 @@ let package = Package(
             targets: ["FaceLiveness"]),
     ],
     dependencies: [
-        .package(url: "https://github.com/aws-amplify/amplify-swift", exact: "2.27.2")
+        // TODO: Change this before merge to main
+        .package(url: "https://github.com/aws-amplify/amplify-swift", branch: "feat/no-light-support")
     ],
     targets: [
         .target(

Package.resolved

@@ -6,6 +6,7 @@
 //
 
 import Foundation
+@_spi(PredictionsFaceLiveness) import AWSPredictionsPlugin
 
 struct DetectedFace {
     var boundingBox: CGRect
@@ -19,7 +20,8 @@ struct DetectedFace {
 
     let confidence: Float
 
-    func boundingBoxFromLandmarks(ovalRect: CGRect) -> CGRect {
+    func boundingBoxFromLandmarks(ovalRect: CGRect,
+                                  ovalMatchChallenge: FaceLivenessSession.OvalMatchChallenge) -> CGRect {
         let alpha = 2.0
         let gamma = 1.8
         let ow = (alpha * pupilDistance + gamma * faceHeight) / 2
@@ -34,7 +36,7 @@ struct DetectedFace {
         }
 
         let faceWidth = ow
-        let faceHeight = 1.618 * faceWidth
+        let faceHeight = ovalMatchChallenge.oval.heightWidthRatio * faceWidth
         let faceBoxBottom = boundingBox.maxY
         let faceBoxTop = faceBoxBottom - faceHeight
         let faceBoxLeft = min(cx - ow / 2, rightEar.x)

Package.swift

@@ -12,6 +12,7 @@ import Accelerate
 import CoreGraphics
 import CoreImage
 import VideoToolbox
+@_spi(PredictionsFaceLiveness) import AWSPredictionsPlugin
 
 enum FaceDetectorShortRange {}
 
@@ -33,11 +34,16 @@ extension FaceDetectorShortRange {
             )
         }
 
+        weak var faceDetectionSessionConfiguration: FaceDetectionSessionConfigurationWrapper?
         weak var detectionResultHandler: FaceDetectionResultHandler?
 
         func setResultHandler(detectionResultHandler: FaceDetectionResultHandler) {
             self.detectionResultHandler = detectionResultHandler
         }
+        
+        func setFaceDetectionSessionConfigurationWrapper(configuration: FaceDetectionSessionConfigurationWrapper) {
+            self.faceDetectionSessionConfiguration = configuration
+        }
 
         func detectFaces(from buffer: CVPixelBuffer) {
             let faces = prediction(for: buffer)
@@ -105,10 +111,17 @@ extension FaceDetectorShortRange {
                     count: confidenceScoresCapacity
                 )
             )
+            
+            let blazeFaceDetectionThreshold: Float
+            if let sessionConfiguration = faceDetectionSessionConfiguration?.sessionConfiguration {
+                blazeFaceDetectionThreshold = Float(sessionConfiguration.ovalMatchChallenge.faceDetectionThreshold)
+            } else {
+                blazeFaceDetectionThreshold = confidenceScoreThreshold
+            }
 
             var passingConfidenceScoresIndices = confidenceScores
                 .enumerated()
-                .filter { $0.element >= confidenceScoreThreshold }
+                .filter { $0.element >=  blazeFaceDetectionThreshold}
                 .sorted(by: {
                     $0.element > $1.element
                 })

Sources/FaceLiveness/FaceDetection/BlazeFace/DetectedFace.swift

@@ -6,6 +6,7 @@
 //
 
 import AVFoundation
+@_spi(PredictionsFaceLiveness) import AWSPredictionsPlugin
 
 protocol FaceDetector {
     func detectFaces(from buffer: CVPixelBuffer)
@@ -16,6 +17,10 @@ protocol FaceDetectionResultHandler: AnyObject {
     func process(newResult: FaceDetectionResult)
 }
 
+protocol FaceDetectionSessionConfigurationWrapper: AnyObject {
+    var sessionConfiguration: FaceLivenessSession.SessionConfiguration? { get }
+}
+
 enum FaceDetectionResult {
     case noFace
     case singleFace(DetectedFace)

Sources/FaceLiveness/FaceDetection/BlazeFace/FaceDetectorShortRange+Model.swift

@@ -6,35 +6,49 @@
 //
 
 import SwiftUI
+@_spi(PredictionsFaceLiveness) import AWSPredictionsPlugin
 
 struct GetReadyPageView: View {
     let beginCheckButtonDisabled: Bool
     let onBegin: () -> Void
-
+    let challenge: Challenge
+    
     init(
         onBegin: @escaping () -> Void,
-        beginCheckButtonDisabled: Bool = false
+        beginCheckButtonDisabled: Bool = false,
+        challenge: Challenge
     ) {
         self.onBegin = onBegin
         self.beginCheckButtonDisabled = beginCheckButtonDisabled
+        self.challenge = challenge
     }
 
     var body: some View {
         VStack {
             ZStack {
                 CameraPreviewView()
-                VStack {
-                    WarningBox(
-                        titleText: LocalizedStrings.get_ready_photosensitivity_title,
-                        bodyText: LocalizedStrings.get_ready_photosensitivity_description,
-                        popoverContent: { photosensitivityWarningPopoverContent }
-                    )
-                    .accessibilityElement(children: .combine)
-                    Text(LocalizedStrings.preview_center_your_face_text)
-                        .font(.title)
-                        .multilineTextAlignment(.center)
-                    Spacer()
-                }.padding()
+                switch self.challenge.type {
+                case .faceMovementChallenge:
+                    VStack {
+                        Text(LocalizedStrings.preview_center_your_face_text)
+                            .font(.title)
+                            .multilineTextAlignment(.center)
+                        Spacer()
+                    }.padding()
+                case . faceMovementAndLightChallenge:
+                    VStack {
+                        WarningBox(
+                            titleText: LocalizedStrings.get_ready_photosensitivity_title,
+                            bodyText: LocalizedStrings.get_ready_photosensitivity_description,
+                            popoverContent: { photosensitivityWarningPopoverContent }
+                        )
+                        .accessibilityElement(children: .combine)
+                        Text(LocalizedStrings.preview_center_your_face_text)
+                            .font(.title)
+                            .multilineTextAlignment(.center)
+                        Spacer()
+                    }.padding()
+                }
             }
             beginCheckButton
         }
@@ -72,6 +86,8 @@ struct GetReadyPageView: View {
 
 struct GetReadyPageView_Previews: PreviewProvider {
     static var previews: some View {
-        GetReadyPageView(onBegin: {})
+        GetReadyPageView(onBegin: {}, 
+                         challenge: .init(version: "2.0.0",
+                                              type: .faceMovementAndLightChallenge))
     }
 }

Sources/FaceLiveness/FaceDetection/FaceDetector.swift

@@ -7,6 +7,7 @@
 
 import SwiftUI
 import Combine
+@_spi(PredictionsFaceLiveness) import AWSPredictionsPlugin
 
 struct InstructionContainerView: View {
     @ObservedObject var viewModel: FaceLivenessDetectionViewModel
@@ -97,13 +98,29 @@ struct InstructionContainerView: View {
                     argument: LocalizedStrings.challenge_verifying
                 )
             }
-        case .faceMatched:
+        case .completedNoLightCheck:
             InstructionView(
-                text: LocalizedStrings.challenge_instruction_hold_still,
-                backgroundColor: .livenessPrimaryBackground,
-                textColor: .livenessPrimaryLabel,
-                font: .title
+                text: LocalizedStrings.challenge_verifying,
+                backgroundColor: .livenessBackground
             )
+            .onAppear {
+                UIAccessibility.post(
+                    notification: .announcement,
+                    argument: LocalizedStrings.challenge_verifying
+                )
+            }
+        case .faceMatched:
+            if let challenge = viewModel.challenge,
+               case .faceMovementAndLightChallenge = challenge.type {
+                InstructionView(
+                    text: LocalizedStrings.challenge_instruction_hold_still,
+                    backgroundColor: .livenessPrimaryBackground,
+                    textColor: .livenessPrimaryLabel,
+                    font: .title
+                )
+            } else {
+                EmptyView()
+            }
         default:
             EmptyView()
         }