[mob] Conservative threshold for combination of low score and blur

mobile/lib/services/machine_learning/face_ml/face_clustering/face_clustering_service.dart

@@ -454,6 +454,8 @@ class FaceClusteringService {
           blurValue: face.blurValue,
           badFace: face.faceScore < kMinimumQualityFaceScore ||
               face.blurValue < kLaplacianSoftThreshold ||
+              (face.blurValue < kLaplacianVerySoftThreshold &&
+                  face.faceScore < kMediumQualityFaceScore) ||
               face.isSideways,
           vEmbedding: Vector.fromList(
             EVector.fromBuffer(face.embeddingBytes).values,

mobile/lib/services/machine_learning/face_ml/face_filtering/face_filtering_constants.dart

@@ -3,12 +3,15 @@ import 'package:photos/services/machine_learning/face_ml/face_detection/face_det
 /// Blur detection threshold
 const kLaplacianHardThreshold = 15;
 const kLaplacianSoftThreshold = 100;
+const kLaplacianVerySoftThreshold = 200;
 
 /// Default blur value
 const kLapacianDefault = 10000.0;
 
 /// The minimum score for a face to be considered a high quality face for clustering and person detection
 const kMinimumQualityFaceScore = 0.80;
+const kMediumQualityFaceScore = 0.85;
+const kHighQualityFaceScore = 0.90;
 
 /// The minimum score for a face to be detected, regardless of quality. Use [kMinimumQualityFaceScore] for high quality faces.
 const kMinFaceDetectionScore = FaceDetectionService.kMinScoreSigmoidThreshold;