Don't save preview frames if recording is not enabled (#13656)

* Simplify check

* Don't write frames

* Write frames only if recording enabled

frigate/output/preview.py

@@ -12,6 +12,7 @@ from pathlib import Path
 import cv2
 import numpy as np
 
+from frigate.comms.config_updater import ConfigSubscriber
 from frigate.comms.inter_process import InterProcessRequestor
 from frigate.config import CameraConfig, RecordQualityEnum
 from frigate.const import CACHE_DIR, CLIPS_DIR, INSERT_PREVIEW, PREVIEW_FRAME_TYPE
@@ -170,6 +171,7 @@ class PreviewRecorder:
 
         # create communication for finished previews
         self.requestor = InterProcessRequestor()
+        self.config_subscriber = ConfigSubscriber(f"config/record/{self.config.name}")
 
         y, u1, u2, v1, v2 = get_yuv_crop(
             self.config.frame_shape_yuv,
@@ -243,6 +245,9 @@ class PreviewRecorder:
         frame_time: float,
     ) -> bool:
         """Decide if this frame should be added to PREVIEW."""
+        if not self.config.record.enabled:
+            return False
+
         active_objs = get_active_objects(
             frame_time, self.config, current_tracked_objects
         )
@@ -300,6 +305,12 @@ class PreviewRecorder:
         frame_time: float,
         frame,
     ) -> bool:
+        # check for updated record config
+        _, updated_record_config = self.config_subscriber.check_for_update()
+
+        if updated_record_config:
+            self.config.record = updated_record_config
+
         # always write the first frame
         if self.start_time == 0:
             self.start_time = frame_time
@@ -309,14 +320,18 @@ class PreviewRecorder:
 
         # check if PREVIEW clip should be generated and cached frames reset
         if frame_time >= self.segment_end:
-            # save last frame to ensure consistent duration
-            self.output_frames.append(frame_time)
-            self.write_frame_to_cache(frame_time, frame)
-            FFMpegConverter(
-                self.config,
-                self.output_frames,
-                self.requestor,
-            ).start()
+            if len(self.output_frames) > 0:
+                # save last frame to ensure consistent duration
+                if self.config.record:
+                    self.output_frames.append(frame_time)
+                    self.write_frame_to_cache(frame_time, frame)
+
+                # write the preview if any frames exist for this hour
+                FFMpegConverter(
+                    self.config,
+                    self.output_frames,
+                    self.requestor,
+                ).start()
 
             # reset frame cache
             self.segment_end = (
@@ -330,8 +345,10 @@ class PreviewRecorder:
             self.output_frames: list[float] = []
 
             # include first frame to ensure consistent duration
-            self.output_frames.append(frame_time)
-            self.write_frame_to_cache(frame_time, frame)
+            if self.config.record.enabled:
+                self.output_frames.append(frame_time)
+                self.write_frame_to_cache(frame_time, frame)
+
             return True
         elif self.should_write_frame(current_tracked_objects, motion_boxes, frame_time):
             self.output_frames.append(frame_time)