update

ultralytics/trackers/basetrack.py

@@ -0,0 +1,105 @@
+# Ultralytics YOLO 🚀, AGPL-3.0 license
+"""This module defines the base classes and structures for object tracking in YOLO."""
+
+from collections import OrderedDict
+
+import numpy as np
+
+
+class TrackState:
+    """
+    Enumeration class representing the possible states of an object being tracked.
+
+    Attributes:
+        New (int): State when the object is newly detected.
+        Tracked (int): State when the object is successfully tracked in subsequent frames.
+        Lost (int): State when the object is no longer tracked.
+        Removed (int): State when the object is removed from tracking.
+    """
+
+    New = 0
+    Tracked = 1
+    Lost = 2
+    Removed = 3
+
+
+class BaseTrack:
+    """
+    Base class for object tracking, providing foundational attributes and methods.
+
+    Attributes:
+        _count (int): Class-level counter for unique track IDs.
+        track_id (int): Unique identifier for the track.
+        is_activated (bool): Flag indicating whether the track is currently active.
+        state (TrackState): Current state of the track.
+        history (OrderedDict): Ordered history of the track's states.
+        features (list): List of features extracted from the object for tracking.
+        curr_feature (any): The current feature of the object being tracked.
+        score (float): The confidence score of the tracking.
+        start_frame (int): The frame number where tracking started.
+        frame_id (int): The most recent frame ID processed by the track.
+        time_since_update (int): Frames passed since the last update.
+        location (tuple): The location of the object in the context of multi-camera tracking.
+
+    Methods:
+        end_frame: Returns the ID of the last frame where the object was tracked.
+        next_id: Increments and returns the next global track ID.
+        activate: Abstract method to activate the track.
+        predict: Abstract method to predict the next state of the track.
+        update: Abstract method to update the track with new data.
+        mark_lost: Marks the track as lost.
+        mark_removed: Marks the track as removed.
+        reset_id: Resets the global track ID counter.
+    """
+
+    _count = 0
+
+    def __init__(self):
+        """Initializes a new track with unique ID and foundational tracking attributes."""
+        self.track_id = 0
+        self.is_activated = False
+        self.state = TrackState.New
+        self.history = OrderedDict()
+        self.features = []
+        self.curr_feature = None
+        self.score = 0
+        self.start_frame = 0
+        self.frame_id = 0
+        self.time_since_update = 0
+        self.location = (np.inf, np.inf)
+
+    @property
+    def end_frame(self):
+        """Return the last frame ID of the track."""
+        return self.frame_id
+
+    @staticmethod
+    def next_id():
+        """Increment and return the global track ID counter."""
+        BaseTrack._count += 1
+        return BaseTrack._count
+
+    def activate(self, *args):
+        """Abstract method to activate the track with provided arguments."""
+        raise NotImplementedError
+
+    def predict(self):
+        """Abstract method to predict the next state of the track."""
+        raise NotImplementedError
+
+    def update(self, *args, **kwargs):
+        """Abstract method to update the track with new observations."""
+        raise NotImplementedError
+
+    def mark_lost(self):
+        """Mark the track as lost."""
+        self.state = TrackState.Lost
+
+    def mark_removed(self):
+        """Mark the track as removed."""
+        self.state = TrackState.Removed
+
+    @staticmethod
+    def reset_id():
+        """Reset the global track ID counter."""
+        BaseTrack._count = 0