From fc7f9cd1a897288f0be2afbd77f259a46fe78198 Mon Sep 17 00:00:00 2001
From: Nicolas Mowen <nickmowen213@gmail.com>
Date: Wed, 26 Mar 2025 06:20:05 -0600
Subject: [PATCH] Adjust number of required faces based on detection type

---
 frigate/data_processing/real_time/face.py | 63 ++++++++++++-----------
 1 file changed, 32 insertions(+), 31 deletions(-)

diff --git a/frigate/data_processing/real_time/face.py b/frigate/data_processing/real_time/face.py
index e20dad633..16d625c2b 100644
--- a/frigate/data_processing/real_time/face.py
+++ b/frigate/data_processing/real_time/face.py
@@ -36,36 +36,6 @@ MAX_DETECTION_HEIGHT = 1080
 MIN_MATCHING_FACES = 2
 
 
-def weighted_average_by_area(results_list: list[tuple[str, float, int]]):
-    if len(results_list) < 3:
-        return "unknown", 0.0
-
-    score_count = {}
-    weighted_scores = {}
-    total_face_areas = {}
-
-    for name, score, face_area in results_list:
-        if name not in weighted_scores:
-            score_count[name] = 1
-            weighted_scores[name] = 0.0
-            total_face_areas[name] = 0.0
-        else:
-            score_count[name] += 1
-
-        weighted_scores[name] += score * face_area
-        total_face_areas[name] += face_area
-
-    prominent_name = max(score_count)
-
-    # if a single name is not prominent in the history then we are not confident
-    if score_count[prominent_name] / len(results_list) < 0.65:
-        return "unknown", 0.0
-
-    return prominent_name, weighted_scores[prominent_name] / total_face_areas[
-        prominent_name
-    ]
-
-
 class FaceRealTimeProcessor(RealTimeProcessorApi):
     def __init__(
         self,
@@ -288,7 +258,7 @@ class FaceRealTimeProcessor(RealTimeProcessorApi):
         self.person_face_history[id].append(
             (sub_label, score, face_frame.shape[0] * face_frame.shape[1])
         )
-        (weighted_sub_label, weighted_score) = weighted_average_by_area(
+        (weighted_sub_label, weighted_score) = self.weighted_average_by_area(
             self.person_face_history[id]
         )
 
@@ -415,3 +385,34 @@ class FaceRealTimeProcessor(RealTimeProcessorApi):
     def expire_object(self, object_id: str):
         if object_id in self.person_face_history:
             self.person_face_history.pop(object_id)
+
+    def weighted_average_by_area(self, results_list: list[tuple[str, float, int]]):
+        min_faces = 1 if self.requires_face_detection else 3
+
+        if len(results_list) < min_faces:
+            return "unknown", 0.0
+
+        score_count = {}
+        weighted_scores = {}
+        total_face_areas = {}
+
+        for name, score, face_area in results_list:
+            if name not in weighted_scores:
+                score_count[name] = 1
+                weighted_scores[name] = 0.0
+                total_face_areas[name] = 0.0
+            else:
+                score_count[name] += 1
+
+            weighted_scores[name] += score * face_area
+            total_face_areas[name] += face_area
+
+        prominent_name = max(score_count)
+
+        # if a single name is not prominent in the history then we are not confident
+        if score_count[prominent_name] / len(results_list) < 0.65:
+            return "unknown", 0.0
+
+        return prominent_name, weighted_scores[prominent_name] / total_face_areas[
+            prominent_name
+        ]