Add multiple lines graph support in `analytics` 8.2.26 (#13214)

Co-authored-by: UltralyticsAssistant <web@ultralytics.com>
Co-authored-by: Glenn Jocher <glenn.jocher@ultralytics.com>

docs/en/guides/analytics.md

@@ -72,6 +72,66 @@ This guide provides a comprehensive overview of three fundamental types of data
         cv2.destroyAllWindows()
         ```
     
+    === "Multiple Lines"
+
+        ```python
+        import cv2
+        from ultralytics import YOLO, solutions
+
+        model = YOLO("yolov8s.pt")
+
+        cap = cv2.VideoCapture("Path/to/video/file.mp4")
+        assert cap.isOpened(), "Error reading video file"
+        w, h, fps = (int(cap.get(x)) for x in (cv2.CAP_PROP_FRAME_WIDTH, cv2.CAP_PROP_FRAME_HEIGHT, cv2.CAP_PROP_FPS))
+        out = cv2.VideoWriter("multiple_line_plot.avi", cv2.VideoWriter_fourcc(*"MJPG"), fps, (w, h))
+
+        analytics = solutions.Analytics(
+            type="line",
+            writer=out,
+            im0_shape=(w, h),
+            view_img=True,
+            max_points=200,
+        )
+
+        frame_count = 0
+        data = {}
+        labels = []
+
+        while cap.isOpened():
+            success, frame = cap.read()
+
+            if success:
+                frame_count += 1
+
+                results = model.track(frame, persist=True)
+
+                if results[0].boxes.id is not None:
+                    boxes = results[0].boxes.xyxy.cpu()
+                    track_ids = results[0].boxes.id.int().cpu().tolist()
+                    clss = results[0].boxes.cls.cpu().tolist()
+
+                    for box, track_id, cls in zip(boxes, track_ids, clss):
+                        # Store each class label
+                        if model.names[int(cls)] not in labels:
+                            labels.append(model.names[int(cls)])
+
+                        # Store each class count
+                        if model.names[int(cls)] in data:
+                            data[model.names[int(cls)]] += 1
+                        else:
+                            data[model.names[int(cls)]] = 0
+
+                # update lines every frame
+                analytics.update_multiple_lines(data, labels, frame_count)
+                data = {}  # clear the data list for next frame
+            else:
+                break
+
+        cap.release()
+        out.release()
+        cv2.destroyAllWindows()
+        ```
+
     === "Pie Chart"
 
         ```python
@@ -175,7 +235,7 @@ This guide provides a comprehensive overview of three fundamental types of data
 Here's a table with the `Analytics` arguments:
 
 | Name         | Type              | Default       | Description                                                                      |
-|--------------|-------------------|---------------|-------------------------------------|
+|--------------|-------------------|---------------|----------------------------------------------------------------------------------|
 | `type`       | `str`             | `None`        | Type of data or object.                                                          |
 | `im0_shape`  | `tuple`           | `None`        | Shape of the initial image.                                                      |
 | `writer`     | `cv2.VideoWriter` | `None`        | Object for writing video files.                                                  |
@@ -189,6 +249,7 @@ Here's a table with the `Analytics` arguments:
 | `fontsize`   | `int`             | `13`          | Font size for text.                                                              |
 | `view_img`   | `bool`            | `False`       | Flag to display the image or video.                                              |
 | `save_img`   | `bool`            | `True`        | Flag to save the image or video.                                                 |
+| `max_points` | `int`             | `50`          | For multiple lines, total points drawn on frame, before deleting initial points. |
 
 ### Arguments `model.track`
 

ultralytics/__init__.py

@@ -1,6 +1,6 @@
 # Ultralytics YOLO 🚀, AGPL-3.0 license
 
-__version__ = "8.2.25"
+__version__ = "8.2.26"
 
 import os
 

ultralytics/solutions/analytics.py

@@ -1,5 +1,6 @@
 # Ultralytics YOLO 🚀, AGPL-3.0 license
 
+import warnings
 from itertools import cycle
 
 import cv2
@@ -27,6 +28,7 @@ class Analytics:
         fontsize=13,
         view_img=False,
         save_img=True,
+        max_points=50,
     ):
         """
         Initialize the Analytics class with various chart types.
@@ -45,6 +47,7 @@ class Analytics:
             fontsize (int): Font size for chart text.
             view_img (bool): Whether to display the image.
             save_img (bool): Whether to save the image.
+            max_points (int): Specifies when to remove the oldest points in a graph for multiple lines.
         """
 
         self.bg_color = bg_color
@@ -53,12 +56,14 @@ class Analytics:
         self.save_img = save_img
         self.title = title
         self.writer = writer
+        self.max_points = max_points
 
         # Set figure size based on image shape
         figsize = (im0_shape[0] / 100, im0_shape[1] / 100)
 
         if type == "line":
             # Initialize line plot
+            self.lines = {}
             fig = Figure(facecolor=self.bg_color, figsize=figsize)
             self.canvas = FigureCanvas(fig)
             self.ax = fig.add_subplot(111, facecolor=self.bg_color)
@@ -112,9 +117,53 @@ class Analytics:
         self.ax.autoscale_view()
         self.canvas.draw()
         im0 = np.array(self.canvas.renderer.buffer_rgba())
-        im0 = cv2.cvtColor(im0[:, :, :3], cv2.COLOR_RGBA2BGR)
+        self.write_and_display_line(im0)
 
-        # Display and save the updated graph
+    def update_multiple_lines(self, counts_dict, labels_list, frame_number):
+        """
+        Update the line graph with multiple classes.
+
+        Args:
+            counts_dict (int): Dictionary include each class counts.
+            labels_list (int): list include each classes names.
+            frame_number (int): The current frame number.
+        """
+        warnings.warn("Display is not supported for multiple lines, output will be stored normally!")
+        for obj in labels_list:
+            if obj not in self.lines:
+                (line,) = self.ax.plot([], [], label=obj, marker="o", markersize=15)
+                self.lines[obj] = line
+
+            x_data = self.lines[obj].get_xdata()
+            y_data = self.lines[obj].get_ydata()
+
+            # Remove the initial point if the number of points exceeds max_points
+            if len(x_data) >= self.max_points:
+                x_data = np.delete(x_data, 0)
+                y_data = np.delete(y_data, 0)
+
+            x_data = np.append(x_data, float(frame_number))  # Ensure frame_number is converted to float
+            y_data = np.append(y_data, float(counts_dict.get(obj, 0)))  # Ensure total_count is converted to float
+            self.lines[obj].set_data(x_data, y_data)
+
+        self.ax.relim()
+        self.ax.autoscale_view()
+        self.ax.legend()
+        self.canvas.draw()
+
+        im0 = np.array(self.canvas.renderer.buffer_rgba())
+        self.view_img = False  # for multiple line view_img not supported yet, coming soon!
+        self.write_and_display_line(im0)
+
+    def write_and_display_line(self, im0):
+        """
+        Write and display the line graph
+        Args:
+            im0 (ndarray): Image for processing
+        """
+
+        # convert image to BGR format
+        im0 = cv2.cvtColor(im0[:, :, :3], cv2.COLOR_RGBA2BGR)
         cv2.imshow(self.title, im0) if self.view_img else None
         self.writer.write(im0) if self.save_img else None