From 03e32118ae999c0d0cf1774d6e428eb54cf83991 Mon Sep 17 00:00:00 2001
From: Nicolas Mowen <nickmowen213@gmail.com>
Date: Tue, 9 Jul 2024 06:36:15 -0600
Subject: [PATCH] Simplify empty shm error handling

---
 frigate/object_processing.py | 17 ++++++++---------
 frigate/output/output.py     |  7 +++----
 frigate/util/image.py        | 18 +++++++++++-------
 frigate/video.py             |  9 +++------
 4 files changed, 25 insertions(+), 26 deletions(-)

diff --git a/frigate/object_processing.py b/frigate/object_processing.py
index f9c513d6b..aed850fe3 100644
--- a/frigate/object_processing.py
+++ b/frigate/object_processing.py
@@ -660,13 +660,9 @@ class CameraState:
         # get the new frame
         frame_id = f"{self.name}{frame_time}"
 
-        try:
-            current_frame = self.frame_manager.get(
-                frame_id, self.camera_config.frame_shape_yuv
-            )
-        except FileNotFoundError:
-            logger.error(f"Failed to get {frame_id} from SHM")
-            return
+        current_frame = self.frame_manager.get(
+            frame_id, self.camera_config.frame_shape_yuv
+        )
 
         tracked_objects = self.tracked_objects.copy()
         current_ids = set(current_detections.keys())
@@ -698,7 +694,7 @@ class CameraState:
                 for c in self.callbacks["autotrack"]:
                     c(self.name, updated_obj, frame_time)
 
-            if thumb_update:
+            if thumb_update and current_frame is not None:
                 # ensure this frame is stored in the cache
                 if (
                     updated_obj.thumbnail_data["frame_time"] == frame_time
@@ -858,7 +854,10 @@ class CameraState:
             self.current_frame_time = frame_time
             self.motion_boxes = motion_boxes
             self.regions = regions
-            self._current_frame = current_frame
+
+            if current_frame is not None:
+                self._current_frame = current_frame
+
             if self.previous_frame_id is not None:
                 self.frame_manager.close(self.previous_frame_id)
             self.previous_frame_id = frame_id
diff --git a/frigate/output/output.py b/frigate/output/output.py
index 5904f0b10..6339e2b9c 100644
--- a/frigate/output/output.py
+++ b/frigate/output/output.py
@@ -94,10 +94,9 @@ def output_frames(
 
         frame_id = f"{camera}{frame_time}"
 
-        try:
-            frame = frame_manager.get(frame_id, config.cameras[camera].frame_shape_yuv)
-        except FileNotFoundError:
-            logger.error(f"Failed to get {frame_id} from SHM")
+        frame = frame_manager.get(frame_id, config.cameras[camera].frame_shape_yuv)
+
+        if frame is None:
             continue
 
         # send camera frame to ffmpeg process if websockets are connected
diff --git a/frigate/util/image.py b/frigate/util/image.py
index cb8fd18ce..a3619193f 100644
--- a/frigate/util/image.py
+++ b/frigate/util/image.py
@@ -694,13 +694,17 @@ class SharedMemoryFrameManager(FrameManager):
         self.shm_store[name] = shm
         return shm.buf
 
-    def get(self, name: str, shape):
-        if name in self.shm_store:
-            shm = self.shm_store[name]
-        else:
-            shm = shared_memory.SharedMemory(name=name)
-            self.shm_store[name] = shm
-        return np.ndarray(shape, dtype=np.uint8, buffer=shm.buf)
+    def get(self, name: str, shape) -> Optional[np.ndarray]:
+        try:
+            if name in self.shm_store:
+                shm = self.shm_store[name]
+            else:
+                shm = shared_memory.SharedMemory(name=name)
+                self.shm_store[name] = shm
+            return np.ndarray(shape, dtype=np.uint8, buffer=shm.buf)
+        except FileNotFoundError:
+            logger.error(f"Failed to get {name} from SHM")
+            return None
 
     def close(self, name: str):
         if name in self.shm_store:
diff --git a/frigate/video.py b/frigate/video.py
index 88a265381..3397de6e4 100755
--- a/frigate/video.py
+++ b/frigate/video.py
@@ -575,12 +575,9 @@ def process_frames(
         current_frame_time.value = frame_time
         ptz_metrics["ptz_frame_time"].value = frame_time
 
-        try:
-            frame = frame_manager.get(
-                f"{camera_name}{frame_time}", (frame_shape[0] * 3 // 2, frame_shape[1])
-            )
-        except FileNotFoundError:
-            frame = None
+        frame = frame_manager.get(
+            f"{camera_name}{frame_time}", (frame_shape[0] * 3 // 2, frame_shape[1])
+        )
 
         if frame is None:
             logger.info(f"{camera_name}: frame {frame_time} is not in memory store.")