Add ability to restream birdseye (#4761)

* Try using RTSP for restream

* Add ability to get snapshot of birdseye when birdseye restream is enabled

* Write to pipe instead of encoding mpeg1

* Write to cache instead

* Use const for location

* Formatting

* Add hardware encoding for birdseye based on ffmpeg preset

* Provide framerate

* Adjust args

* Fix order

* Delete pipe file if it exists

* Cleanup spacing

* Fix spacing

frigate/object_processing.py

@@ -880,6 +880,12 @@ class TrackedObjectProcessor(threading.Thread):
             return {}
 
     def get_current_frame(self, camera, draw_options={}):
+        if camera == "birdseye":
+            return self.frame_manager.get(
+                "birdseye",
+                (self.config.birdseye.height * 3 // 2, self.config.birdseye.width),
+            )
+
         return self.camera_states[camera].get_current_frame(draw_options)
 
     def get_current_frame_time(self, camera) -> int: