Use identifier field for unknown license plates (#17123)

* backend

* backend fixes

* api for search queries

* frontend

* docs

* add filterable scroll list to more filters pane for identifiers

* always publish identifier

frigate/api/app.py

@@ -619,6 +619,39 @@ def get_sub_labels(split_joined: Optional[int] = None):
     return JSONResponse(content=sub_labels)
 
 
+@router.get("/identifiers")
+def get_identifiers(split_joined: Optional[int] = None):
+    try:
+        events = Event.select(Event.data).distinct()
+    except Exception:
+        return JSONResponse(
+            content=({"success": False, "message": "Failed to get identifiers"}),
+            status_code=404,
+        )
+
+    identifiers = []
+    for e in events:
+        if e.data is not None and "identifier" in e.data:
+            identifiers.append(e.data["identifier"])
+
+    while None in identifiers:
+        identifiers.remove(None)
+
+    if split_joined:
+        original_identifiers = identifiers.copy()
+        for identifier in original_identifiers:
+            if identifier and "," in identifier:
+                identifiers.remove(identifier)
+                parts = identifier.split(",")
+                for part in parts:
+                    if part.strip() not in identifiers:
+                        identifiers.append(part.strip())
+
+    identifiers = list(set(identifiers))
+    identifiers.sort()
+    return JSONResponse(content=identifiers)
+
+
 @router.get("/timeline")
 def timeline(camera: str = "all", limit: int = 100, source_id: Optional[str] = None):
     clauses = []

frigate/api/defs/query/events_query_parameters.py

@@ -27,6 +27,7 @@ class EventsQueryParams(BaseModel):
     max_score: Optional[float] = None
     min_speed: Optional[float] = None
     max_speed: Optional[float] = None
+    identifier: Optional[str] = "all"
     is_submitted: Optional[int] = None
     min_length: Optional[float] = None
     max_length: Optional[float] = None
@@ -55,6 +56,7 @@ class EventsSearchQueryParams(BaseModel):
     max_score: Optional[float] = None
     min_speed: Optional[float] = None
     max_speed: Optional[float] = None
+    identifier: Optional[str] = "all"
     sort: Optional[str] = None
 
 

frigate/api/event.py

@@ -101,6 +101,7 @@ def events(params: EventsQueryParams = Depends()):
     min_length = params.min_length
     max_length = params.max_length
     event_id = params.event_id
+    identifier = params.identifier
 
     sort = params.sort
 
@@ -158,6 +159,32 @@ def events(params: EventsQueryParams = Depends()):
         sub_label_clause = reduce(operator.or_, sub_label_clauses)
         clauses.append((sub_label_clause))
 
+    if identifier != "all":
+        # use matching so joined identifiers are included
+        # for example an identifier 'ABC123' would get events
+        # with identifiers 'ABC123' and 'ABC123, XYZ789'
+        identifier_clauses = []
+        filtered_identifiers = identifier.split(",")
+
+        if "None" in filtered_identifiers:
+            filtered_identifiers.remove("None")
+            identifier_clauses.append((Event.data["identifier"].is_null()))
+
+        for identifier in filtered_identifiers:
+            # Exact matching plus list inclusion
+            identifier_clauses.append(
+                (Event.data["identifier"].cast("text") == identifier)
+            )
+            identifier_clauses.append(
+                (Event.data["identifier"].cast("text") % f"*{identifier},*")
+            )
+            identifier_clauses.append(
+                (Event.data["identifier"].cast("text") % f"*, {identifier}*")
+            )
+
+        identifier_clause = reduce(operator.or_, identifier_clauses)
+        clauses.append((identifier_clause))
+
     if zones != "all":
         # use matching so events with multiple zones
         # still match on a search where any zone matches
@@ -340,6 +367,8 @@ def events_explore(limit: int = 10):
                         "average_estimated_speed",
                         "velocity_angle",
                         "path_data",
+                        "identifier",
+                        "identifier_score",
                     ]
                 },
                 "event_count": label_counts[event.label],
@@ -397,6 +426,7 @@ def events_search(request: Request, params: EventsSearchQueryParams = Depends())
     has_clip = params.has_clip
     has_snapshot = params.has_snapshot
     is_submitted = params.is_submitted
+    identifier = params.identifier
 
     # for similarity search
     event_id = params.event_id
@@ -466,6 +496,32 @@ def events_search(request: Request, params: EventsSearchQueryParams = Depends())
 
         event_filters.append((reduce(operator.or_, zone_clauses)))
 
+    if identifier != "all":
+        # use matching so joined identifiers are included
+        # for example an identifier 'ABC123' would get events
+        # with identifiers 'ABC123' and 'ABC123, XYZ789'
+        identifier_clauses = []
+        filtered_identifiers = identifier.split(",")
+
+        if "None" in filtered_identifiers:
+            filtered_identifiers.remove("None")
+            identifier_clauses.append((Event.data["identifier"].is_null()))
+
+        for identifier in filtered_identifiers:
+            # Exact matching plus list inclusion
+            identifier_clauses.append(
+                (Event.data["identifier"].cast("text") == identifier)
+            )
+            identifier_clauses.append(
+                (Event.data["identifier"].cast("text") % f"*{identifier},*")
+            )
+            identifier_clauses.append(
+                (Event.data["identifier"].cast("text") % f"*, {identifier}*")
+            )
+
+        identifier_clause = reduce(operator.or_, identifier_clauses)
+        event_filters.append((identifier_clause))
+
     if after:
         event_filters.append((Event.start_time > after))
 
@@ -627,6 +683,8 @@ def events_search(request: Request, params: EventsSearchQueryParams = Depends())
                 "average_estimated_speed",
                 "velocity_angle",
                 "path_data",
+                "identifier",
+                "identifier_score",
             ]
         }
 
@@ -681,6 +739,7 @@ def events_summary(params: EventsSummaryQueryParams = Depends()):
             Event.camera,
             Event.label,
             Event.sub_label,
+            Event.data,
             fn.strftime(
                 "%Y-%m-%d",
                 fn.datetime(
@@ -695,6 +754,7 @@ def events_summary(params: EventsSummaryQueryParams = Depends()):
             Event.camera,
             Event.label,
             Event.sub_label,
+            Event.data,
             (Event.start_time + seconds_offset).cast("int") / (3600 * 24),
             Event.zones,
         )

frigate/camera/state.py

@@ -137,12 +137,13 @@ class CameraState:
                 # draw the bounding boxes on the frame
                 box = obj["box"]
                 text = (
-                    obj["label"]
+                    obj["sub_label"][0]
                     if (
-                        not obj.get("sub_label")
-                        or not is_label_printable(obj["sub_label"][0])
+                        obj.get("sub_label") and is_label_printable(obj["sub_label"][0])
                     )
-                    else obj["sub_label"][0]
+                    else obj.get("identifier", [None])[0]
+                    if (obj.get("identifier") and obj["identifier"][0])
+                    else obj["label"]
                 )
                 draw_box_with_label(
                     frame_copy,

frigate/comms/event_metadata_updater.py

@@ -14,6 +14,7 @@ class EventMetadataTypeEnum(str, Enum):
     manual_event_end = "manual_event_end"
     regenerate_description = "regenerate_description"
     sub_label = "sub_label"
+    identifier = "identifier"
 
 
 class EventMetadataPublisher(Publisher):

frigate/data_processing/common/license_plate/mixin.py

@@ -1054,13 +1054,19 @@ class LicensePlateProcessingMixin:
                     for plate in plates
                 )
             ),
-            top_plate,
+            None,
         )
 
-        # Send the result to the API
+        # If it's a known plate, publish to sub_label
+        if sub_label is not None:
+            self.sub_label_publisher.publish(
+                EventMetadataTypeEnum.sub_label, (id, sub_label, avg_confidence)
+            )
+
         self.sub_label_publisher.publish(
-            EventMetadataTypeEnum.sub_label, (id, sub_label, avg_confidence)
+            EventMetadataTypeEnum.identifier, (id, top_plate, avg_confidence)
         )
+
         self.detected_license_plates[id] = {
             "plate": top_plate,
             "char_confidences": top_char_confidences,

frigate/events/maintainer.py

@@ -27,6 +27,7 @@ def should_update_db(prev_event: Event, current_event: Event) -> bool:
             or prev_event["average_estimated_speed"]
             != current_event["average_estimated_speed"]
             or prev_event["velocity_angle"] != current_event["velocity_angle"]
+            or prev_event["identifier"] != current_event["identifier"]
             or prev_event["path_data"] != current_event["path_data"]
         ):
             return True
@@ -226,6 +227,11 @@ class EventProcessor(threading.Thread):
                 event[Event.sub_label] = event_data["sub_label"][0]
                 event[Event.data]["sub_label_score"] = event_data["sub_label"][1]
 
+            # only overwrite the identifier in the database if it's set
+            if event_data.get("identifier") is not None:
+                event[Event.data]["identifier"] = event_data["identifier"][0]
+                event[Event.data]["identifier_score"] = event_data["identifier"][1]
+
             (
                 Event.insert(event)
                 .on_conflict(

frigate/track/object_processing.py

@@ -346,6 +346,41 @@ class TrackedObjectProcessor(threading.Thread):
 
         return True
 
+    def set_identifier(
+        self, event_id: str, identifier: str | None, score: float | None
+    ) -> None:
+        """Update identifier for given event id."""
+        tracked_obj: TrackedObject = None
+
+        for state in self.camera_states.values():
+            tracked_obj = state.tracked_objects.get(event_id)
+
+            if tracked_obj is not None:
+                break
+
+        try:
+            event: Event = Event.get(Event.id == event_id)
+        except DoesNotExist:
+            event = None
+
+        if not tracked_obj and not event:
+            return
+
+        if tracked_obj:
+            tracked_obj.obj_data["identifier"] = (identifier, score)
+
+        if event:
+            data = event.data
+            data["identifier"] = identifier
+            if identifier is None:
+                data["identifier_score"] = None
+            elif score is not None:
+                data["identifier_score"] = score
+            event.data = data
+            event.save()
+
+        return True
+
     def create_manual_event(self, payload: tuple) -> None:
         (
             frame_time,
@@ -507,6 +542,9 @@ class TrackedObjectProcessor(threading.Thread):
                 if topic.endswith(EventMetadataTypeEnum.sub_label.value):
                     (event_id, sub_label, score) = payload
                     self.set_sub_label(event_id, sub_label, score)
+                if topic.endswith(EventMetadataTypeEnum.identifier.value):
+                    (event_id, identifier, score) = payload
+                    self.set_identifier(event_id, identifier, score)
                 elif topic.endswith(EventMetadataTypeEnum.manual_event_create.value):
                     self.create_manual_event(payload)
                 elif topic.endswith(EventMetadataTypeEnum.manual_event_end.value):

frigate/track/tracked_object.py

@@ -153,6 +153,8 @@ class TrackedObject:
                     "current_estimated_speed": self.current_estimated_speed,
                     "velocity_angle": self.velocity_angle,
                     "path_data": self.path_data,
+                    "identifier": obj_data.get("identifier"),
+                    "identifier_score": obj_data.get("identifier_score"),
                 }
                 thumb_update = True
 
@@ -365,6 +367,7 @@ class TrackedObject:
             "average_estimated_speed": self.average_estimated_speed,
             "velocity_angle": self.velocity_angle,
             "path_data": self.path_data,
+            "identifier": self.obj_data.get("identifier"),
         }
 
         return event