From 3a877894f1de0ffbadfe8f7a0a838657683e2be9 Mon Sep 17 00:00:00 2001
From: Nick Mowen <nickmowen213@gmail.com>
Date: Mon, 12 Jun 2023 14:13:45 -0600
Subject: [PATCH] Handle vertical cameras more optimally in 2 camera layout

---
 frigate/output.py | 108 +++++++++++++++++++++++++++++++++++-----------
 1 file changed, 83 insertions(+), 25 deletions(-)

diff --git a/frigate/output.py b/frigate/output.py
index ea0a19b90..689c4af2e 100644
--- a/frigate/output.py
+++ b/frigate/output.py
@@ -269,10 +269,90 @@ class BirdsEyeFrameManager:
     def update_frame(self):
         """Update to a new frame for birdseye."""
 
+        def calculate_two_cam_layout(canvas, cameras_to_add: list[str]) -> tuple[any]:
+            """Calculate the optimal layout for 2 cameras."""
+            first_camera = cameras_to_add[0]
+            first_camera_dims = self.cameras[first_camera]["dimensions"].copy()
+            second_camera = cameras_to_add[1]
+            second_camera_dims = self.cameras[second_camera]["dimensions"].copy()
+
+            # check for optimal layout
+            if first_camera_dims[0] + second_camera_dims[0] < canvas_width:
+                # place cameras horizontally
+                first_scaled_width = int(
+                    canvas_height * first_camera_dims[0] / first_camera_dims[1]
+                )
+                second_scaled_width = int(
+                    canvas_height * second_camera_dims[0] / second_camera_dims[1]
+                )
+                first_height = canvas_height
+                second_height = canvas_height
+
+                if first_scaled_width + second_scaled_width > canvas_width:
+                    if first_scaled_width > second_scaled_width:
+                        first_scaled_width = canvas_width - second_scaled_width
+                        first_height = int(
+                            first_scaled_width
+                            * first_camera_dims[1]
+                            / first_camera_dims[0]
+                        )
+                    else:
+                        second_scaled_width = canvas_width - first_scaled_width
+                        second_height = int(
+                            second_scaled_width
+                            * second_camera_dims[1]
+                            / second_camera_dims[0]
+                        )
+
+                return [
+                    [
+                        (
+                            first_camera,
+                            (0, 0, first_scaled_width, first_height),
+                        ),
+                        (
+                            second_camera,
+                            (
+                                first_scaled_width + 1,
+                                0,
+                                second_scaled_width,
+                                second_height,
+                            ),
+                        ),
+                    ],
+                ]
+            elif first_camera_dims[1] + second_camera_dims[1] < canvas_height:
+                # place cameras vertically
+                top_scaled_width = int(
+                    (canvas_height / 2) * first_camera_dims[0] / first_camera_dims[1]
+                )
+                bottom_scaled_width = int(
+                    (canvas_height / 2) * second_camera_dims[0] / second_camera_dims[1]
+                )
+                return [
+                    [
+                        (
+                            first_camera,
+                            (0, 0, top_scaled_width, int(canvas_height / 2)),
+                        )
+                    ],
+                    [
+                        (
+                            second_camera,
+                            (
+                                0,
+                                int(canvas_height / 2),
+                                bottom_scaled_width,
+                                int(canvas_height / 2),
+                            ),
+                        )
+                    ],
+                ]
+
         def calculate_layout(
             canvas, cameras_to_add: list[str], coefficient
         ) -> tuple[any]:
-            """Calculate the optimal layout for cameras."""
+            """Calculate the optimal layout for 3+ cameras."""
             camera_layout: list[list[any]] = []
             camera_layout.append([])
             canvas_aspect = canvas[0] / canvas[1]
@@ -403,31 +483,9 @@ class BirdsEyeFrameManager:
                     ]
                 ]
             elif len(active_cameras) == 2:
-                # split canvas in half for 2 cameras
-                top_camera = active_cameras_to_add[0]
-                top_camera_dims = self.cameras[top_camera]["dimensions"].copy()
-                bottom_camera = active_cameras_to_add[1]
-                bottom_camera_dims = self.cameras[bottom_camera]["dimensions"].copy()
-                top_scaled_width = int(
-                    (canvas_height / 2) * top_camera_dims[0] / top_camera_dims[1]
+                self.camera_layout = calculate_two_cam_layout(
+                    (canvas_width, canvas_height), active_cameras_to_add
                 )
-                bottom_scaled_width = int(
-                    (canvas_height / 2) * bottom_camera_dims[0] / bottom_camera_dims[1]
-                )
-                self.camera_layout = [
-                    [(top_camera, (0, 0, top_scaled_width, int(canvas_height / 2)))],
-                    [
-                        (
-                            bottom_camera,
-                            (
-                                0,
-                                int(canvas_height / 2),
-                                bottom_scaled_width,
-                                int(canvas_height / 2),
-                            ),
-                        )
-                    ],
-                ]
             else:
                 # calculate optimal layout
                 coefficient = 1.0