Implement facenet tflite for small face recognition model (#17402)

This commit is contained in:
Nicolas Mowen
2025-03-27 05:31:29 -06:00
committed by GitHub
parent 0947bffeef
commit 36446ceded
6 changed files with 227 additions and 98 deletions

View File

@@ -10,7 +10,7 @@ from scipy import stats
from frigate.config import FrigateConfig
from frigate.const import MODEL_CACHE_DIR
from frigate.embeddings.onnx.face_embedding import ArcfaceEmbedding
from frigate.embeddings.onnx.face_embedding import ArcfaceEmbedding, FaceNetEmbedding
logger = logging.getLogger(__name__)
@@ -124,83 +124,140 @@ class FaceRecognizer(ABC):
return 1.0
class LBPHRecognizer(FaceRecognizer):
def similarity_to_confidence(
cosine_similarity: float, median=0.3, range_width=0.6, slope_factor=12
):
"""
Default sigmoid function to map cosine similarity to confidence.
Args:
cosine_similarity (float): The input cosine similarity.
median (float): Assumed median of cosine similarity distribution.
range_width (float): Assumed range of cosine similarity distribution (90th percentile - 10th percentile).
slope_factor (float): Adjusts the steepness of the curve.
Returns:
float: The confidence score.
"""
# Calculate slope and bias
slope = slope_factor / range_width
bias = median
# Calculate confidence
confidence = 1 / (1 + np.exp(-slope * (cosine_similarity - bias)))
return confidence
class FaceNetRecognizer(FaceRecognizer):
def __init__(self, config: FrigateConfig):
super().__init__(config)
self.label_map: dict[int, str] = {}
self.recognizer: cv2.face.LBPHFaceRecognizer | None = None
self.mean_embs: dict[int, np.ndarray] = {}
self.face_embedder: FaceNetEmbedding = FaceNetEmbedding()
self.model_builder_queue: queue.Queue | None = None
def clear(self) -> None:
self.face_recognizer = None
self.label_map = {}
self.mean_embs = {}
def run_build_task(self) -> None:
self.model_builder_queue = queue.Queue()
def build_model():
face_embeddings_map: dict[str, list[np.ndarray]] = {}
idx = 0
dir = "/media/frigate/clips/faces"
for name in os.listdir(dir):
if name == "train":
continue
face_folder = os.path.join(dir, name)
if not os.path.isdir(face_folder):
continue
face_embeddings_map[name] = []
for image in os.listdir(face_folder):
img = cv2.imread(os.path.join(face_folder, image))
if img is None:
continue
img = self.align_face(img, img.shape[1], img.shape[0])
emb = self.face_embedder([img])[0].squeeze()
face_embeddings_map[name].append(emb)
idx += 1
self.model_builder_queue.put(face_embeddings_map)
thread = threading.Thread(target=build_model, daemon=True)
thread.start()
def build(self):
if not self.landmark_detector:
self.init_landmark_detector()
return None
labels = []
faces = []
idx = 0
dir = "/media/frigate/clips/faces"
for name in os.listdir(dir):
if name == "train":
continue
face_folder = os.path.join(dir, name)
if not os.path.isdir(face_folder):
continue
self.label_map[idx] = name
for image in os.listdir(face_folder):
img = cv2.imread(os.path.join(face_folder, image))
if img is None:
continue
img = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
img = self.align_face(img, img.shape[1], img.shape[0])
faces.append(img)
labels.append(idx)
idx += 1
if not faces:
if self.model_builder_queue is not None:
try:
face_embeddings_map: dict[str, list[np.ndarray]] = (
self.model_builder_queue.get(timeout=0.1)
)
self.model_builder_queue = None
except queue.Empty:
return
else:
self.run_build_task()
return
self.recognizer: cv2.face.LBPHFaceRecognizer = (
cv2.face.LBPHFaceRecognizer_create(radius=2, threshold=400)
)
self.recognizer.train(faces, np.array(labels))
if not face_embeddings_map:
return
def classify(self, face_image: np.ndarray) -> tuple[str, float] | None:
for name, embs in face_embeddings_map.items():
if embs:
self.mean_embs[name] = stats.trim_mean(embs, 0.15)
logger.debug("Finished building ArcFace model")
def classify(self, face_image):
if not self.landmark_detector:
return None
if not self.label_map or not self.recognizer:
if not self.mean_embs:
self.build()
if not self.recognizer:
if not self.mean_embs:
return None
# face recognition is best run on grayscale images
img = cv2.cvtColor(face_image, cv2.COLOR_BGR2GRAY)
# get blur factor before aligning face
blur_factor = self.get_blur_factor(img)
logger.debug(f"face detected with bluriness {blur_factor}")
blur_factor = self.get_blur_factor(face_image)
logger.debug(f"face detected with blurriness {blur_factor}")
# align face and run recognition
img = self.align_face(img, img.shape[1], img.shape[0])
index, distance = self.recognizer.predict(img)
img = self.align_face(face_image, face_image.shape[1], face_image.shape[0])
embedding = self.face_embedder([img])[0].squeeze()
if index == -1:
return None
score = 0
label = ""
score = (1.0 - (distance / 1000)) * blur_factor
return self.label_map[index], round(score, 2)
for name, mean_emb in self.mean_embs.items():
dot_product = np.dot(embedding, mean_emb)
magnitude_A = np.linalg.norm(embedding)
magnitude_B = np.linalg.norm(mean_emb)
cosine_similarity = dot_product / (magnitude_A * magnitude_B)
confidence = similarity_to_confidence(
cosine_similarity, median=0.5, range_width=0.6
)
if confidence > score:
score = confidence
label = name
return label, round(score * blur_factor, 2)
class ArcFaceRecognizer(FaceRecognizer):
@@ -274,30 +331,6 @@ class ArcFaceRecognizer(FaceRecognizer):
logger.debug("Finished building ArcFace model")
def similarity_to_confidence(
self, cosine_similarity: float, median=0.3, range_width=0.6, slope_factor=12
):
"""
Default sigmoid function to map cosine similarity to confidence.
Args:
cosine_similarity (float): The input cosine similarity.
median (float): Assumed median of cosine similarity distribution.
range_width (float): Assumed range of cosine similarity distribution (90th percentile - 10th percentile).
slope_factor (float): Adjusts the steepness of the curve.
Returns:
float: The confidence score.
"""
# Calculate slope and bias
slope = slope_factor / range_width
bias = median
# Calculate confidence
confidence = 1 / (1 + np.exp(-slope * (cosine_similarity - bias)))
return confidence
def classify(self, face_image):
if not self.landmark_detector:
return None
@@ -312,7 +345,7 @@ class ArcFaceRecognizer(FaceRecognizer):
# get blur factor before aligning face
blur_factor = self.get_blur_factor(face_image)
logger.debug(f"face detected with bluriness {blur_factor}")
logger.debug(f"face detected with blurriness {blur_factor}")
# align face and run recognition
img = self.align_face(face_image, face_image.shape[1], face_image.shape[0])
@@ -327,7 +360,7 @@ class ArcFaceRecognizer(FaceRecognizer):
magnitude_B = np.linalg.norm(mean_emb)
cosine_similarity = dot_product / (magnitude_A * magnitude_B)
confidence = self.similarity_to_confidence(cosine_similarity)
confidence = similarity_to_confidence(cosine_similarity)
if confidence > score:
score = confidence