Add snapshot-clean.png API endpoint (#10510)

* Add snapshot-clean.png API endpoint

* fix lint

* enable on inprogress event

frigate/api/media.py

@@ -935,6 +935,81 @@ def grid_snapshot(camera_name):
         )
 
 
+@MediaBp.route("/events/<id>/snapshot-clean.png")
+def event_snapshot_clean(id):
+    download = request.args.get("download", type=bool)
+    png_bytes = None
+    try:
+        event = Event.get(Event.id == id)
+        snapshot_config = current_app.frigate_config.cameras[event.camera].snapshots
+        if not (snapshot_config.enabled and event.has_snapshot):
+            return make_response(
+                jsonify(
+                    {
+                        "success": False,
+                        "message": "Snapshots and clean_copy must be enabled in the config",
+                    }
+                ),
+                404,
+            )
+        if event.end_time is None:
+            # see if the object is currently being tracked
+            try:
+                camera_states = (
+                    current_app.detected_frames_processor.camera_states.values()
+                )
+                for camera_state in camera_states:
+                    if id in camera_state.tracked_objects:
+                        tracked_obj = camera_state.tracked_objects.get(id)
+                        if tracked_obj is not None:
+                            png_bytes = tracked_obj.get_clean_png()
+                            break
+            except Exception:
+                return make_response(
+                    jsonify({"success": False, "message": "Event not found"}), 404
+                )
+        elif not event.has_snapshot:
+            return make_response(
+                jsonify({"success": False, "message": "Snapshot not available"}), 404
+            )
+    except DoesNotExist:
+        return make_response(
+            jsonify({"success": False, "message": "Event not found"}), 404
+        )
+    if png_bytes is None:
+        try:
+            clean_snapshot_path = os.path.join(
+                CLIPS_DIR, f"{event.camera}-{event.id}-clean.png"
+            )
+            if not os.path.exists(clean_snapshot_path):
+                return make_response(
+                    jsonify(
+                        {"success": False, "message": "Clean snapshot not available"}
+                    ),
+                    404,
+                )
+            with open(
+                os.path.join(CLIPS_DIR, f"{event.camera}-{event.id}-clean.png"), "rb"
+            ) as image_file:
+                png_bytes = image_file.read()
+        except Exception:
+            logger.error(f"Unable to load clean png for event: {event.id}")
+            return make_response(
+                jsonify(
+                    {"success": False, "message": "Unable to load clean png for event"}
+                ),
+                400,
+            )
+    response = make_response(png_bytes)
+    response.headers["Content-Type"] = "image/png"
+    response.headers["Cache-Control"] = "private, max-age=31536000"
+    if download:
+        response.headers["Content-Disposition"] = (
+            f"attachment; filename=snapshot-{id}-clean.png"
+        )
+    return response
+
+
 @MediaBp.route("/events/<id>/snapshot.jpg")
 def event_snapshot(id):
     download = request.args.get("download", type=bool)