From f05ff552ffc41f677b0e6c2d6dbfb2d4c9bccd90 Mon Sep 17 00:00:00 2001
From: Nick Mowen <nickmowen213@gmail.com>
Date: Tue, 17 Oct 2023 14:27:52 -0600
Subject: [PATCH] Use regions grid for startup scan

---
 frigate/util/object.py | 30 ++++++++++++++++++++++++++++++
 frigate/video.py       | 25 ++++++-------------------
 2 files changed, 36 insertions(+), 19 deletions(-)

diff --git a/frigate/util/object.py b/frigate/util/object.py
index 8aefe45a7..046d6818e 100644
--- a/frigate/util/object.py
+++ b/frigate/util/object.py
@@ -114,6 +114,8 @@ def get_camera_regions_grid(
             std_dev = np.std(cell["sizes"])
             mean = np.mean(cell["sizes"])
             logger.debug(f"std dev: {std_dev} mean: {mean}")
+            cell["x"] = x
+            cell["y"] = y
             cell["std_dev"] = std_dev
             cell["mean"] = mean
 
@@ -442,3 +444,31 @@ def get_consolidated_object_detections(detected_object_groups):
                 consolidated_detections.append(sorted_by_area[current_detection_idx])
 
     return consolidated_detections
+
+
+def get_startup_regions(frame_shape: tuple[int], region_min_size: int, region_grid: list[list[dict[str, any]]]) -> list[list[int]]:
+    """Get a list of regions to run on startup."""
+    # return 8 most popular regions for the camera
+    all_cells = np.concatenate(region_grid).flat
+    startup_cells = sorted(all_cells, key=lambda c: len(c["sizes"]), reverse=True)[0:8]
+    regions = []
+
+    for cell in startup_cells:
+        # rest of the cells are empty
+        if not cell["sizes"]:
+            break
+
+        x = frame_shape[1] / GRID_SIZE * (0.5 + cell["x"])
+        y = frame_shape[0] / GRID_SIZE * (0.5 + cell["y"])
+        size = cell["mean"] * frame_shape[1]
+        regions.append(calculate_region(
+            frame_shape,
+            x - size / 2,
+            y - size / 2,
+            x + size / 2,
+            y + size / 2,
+            region_min_size,
+            multiplier=1,
+        ))
+
+    return regions
diff --git a/frigate/video.py b/frigate/video.py
index 68c4175f8..33ace1ad2 100755
--- a/frigate/video.py
+++ b/frigate/video.py
@@ -26,7 +26,6 @@ from frigate.util.builtin import EventsPerSecond, get_tomorrow_at_2
 from frigate.util.image import (
     FrameManager,
     SharedMemoryFrameManager,
-    calculate_region,
     draw_box_with_label,
 )
 from frigate.util.object import (
@@ -37,6 +36,7 @@ from frigate.util.object import (
     get_cluster_region_from_grid,
     get_consolidated_object_detections,
     get_min_region_size,
+    get_startup_regions,
     inside_any,
     intersects_any,
     is_object_filtered,
@@ -520,7 +520,7 @@ def process_frames(
     fps_tracker = EventsPerSecond()
     fps_tracker.start()
 
-    startup_scan_counter = 0
+    startup_scan = True
 
     region_min_size = get_min_region_size(model_config)
 
@@ -626,23 +626,10 @@ def process_frames(
                     regions += motion_regions
 
             # if starting up, get the next startup scan region
-            if startup_scan_counter < 9:
-                ymin = int(frame_shape[0] / 3 * startup_scan_counter / 3)
-                ymax = int(frame_shape[0] / 3 + ymin)
-                xmin = int(frame_shape[1] / 3 * startup_scan_counter / 3)
-                xmax = int(frame_shape[1] / 3 + xmin)
-                regions.append(
-                    calculate_region(
-                        frame_shape,
-                        xmin,
-                        ymin,
-                        xmax,
-                        ymax,
-                        region_min_size,
-                        multiplier=1.2,
-                    )
-                )
-                startup_scan_counter += 1
+            if startup_scan:
+                for region in get_startup_regions(frame_shape, region_min_size, region_grid):
+                    regions.append(region)
+                startup_scan = False
 
             # resize regions and detect
             # seed with stationary objects