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Reference for ultralytics/solutions/speed_estimation.py

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This file is available at https://github.com/ultralytics/ultralytics/blob/main/ultralytics/solutions/speed_estimation.py. If you spot a problem please help fix it by contributing a Pull Request 🛠️. Thank you 🙏!


ultralytics.solutions.speed_estimation.SpeedEstimator

SpeedEstimator(
    names, reg_pts=None, view_img=False, line_thickness=2, spdl_dist_thresh=10
)

A class to estimate the speed of objects in a real-time video stream based on their tracks.

Parameters:

Name Type Description Default
names dict

Dictionary of class names.

required
reg_pts list

List of region points for speed estimation. Defaults to [(20, 400), (1260, 400)].

None
view_img bool

Whether to display the image with annotations. Defaults to False.

False
line_thickness int

Thickness of the lines for drawing boxes and tracks. Defaults to 2.

2
spdl_dist_thresh int

Distance threshold for speed calculation. Defaults to 10.

10
Source code in ultralytics/solutions/speed_estimation.py
def __init__(self, names, reg_pts=None, view_img=False, line_thickness=2, spdl_dist_thresh=10):
    """
    Initializes the SpeedEstimator with the given parameters.

    Args:
        names (dict): Dictionary of class names.
        reg_pts (list, optional): List of region points for speed estimation. Defaults to [(20, 400), (1260, 400)].
        view_img (bool, optional): Whether to display the image with annotations. Defaults to False.
        line_thickness (int, optional): Thickness of the lines for drawing boxes and tracks. Defaults to 2.
        spdl_dist_thresh (int, optional): Distance threshold for speed calculation. Defaults to 10.
    """
    # Region information
    self.reg_pts = reg_pts if reg_pts is not None else [(20, 400), (1260, 400)]

    self.names = names  # Classes names

    # Tracking information
    self.trk_history = defaultdict(list)

    self.view_img = view_img  # bool for displaying inference
    self.tf = line_thickness  # line thickness for annotator
    self.spd = {}  # set for speed data
    self.trkd_ids = []  # list for already speed_estimated and tracked ID's
    self.spdl = spdl_dist_thresh  # Speed line distance threshold
    self.trk_pt = {}  # set for tracks previous time
    self.trk_pp = {}  # set for tracks previous point

    # Check if the environment supports imshow
    self.env_check = check_imshow(warn=True)

estimate_speed

estimate_speed(im0, tracks)

Estimates the speed of objects based on tracking data.

Parameters:

Name Type Description Default
im0 ndarray

Image.

required
tracks list

List of tracks obtained from the object tracking process.

required

Returns:

Type Description
ndarray

The image with annotated boxes and tracks.

Source code in ultralytics/solutions/speed_estimation.py
def estimate_speed(self, im0, tracks):
    """
    Estimates the speed of objects based on tracking data.

    Args:
        im0 (ndarray): Image.
        tracks (list): List of tracks obtained from the object tracking process.

    Returns:
        (ndarray): The image with annotated boxes and tracks.
    """
    if tracks[0].boxes.id is None:
        return im0

    boxes = tracks[0].boxes.xyxy.cpu()
    clss = tracks[0].boxes.cls.cpu().tolist()
    t_ids = tracks[0].boxes.id.int().cpu().tolist()
    annotator = Annotator(im0, line_width=self.tf)
    annotator.draw_region(reg_pts=self.reg_pts, color=(255, 0, 255), thickness=self.tf * 2)

    for box, t_id, cls in zip(boxes, t_ids, clss):
        track = self.trk_history[t_id]
        bbox_center = (float((box[0] + box[2]) / 2), float((box[1] + box[3]) / 2))
        track.append(bbox_center)

        if len(track) > 30:
            track.pop(0)

        trk_pts = np.hstack(track).astype(np.int32).reshape((-1, 1, 2))

        if t_id not in self.trk_pt:
            self.trk_pt[t_id] = 0

        speed_label = f"{int(self.spd[t_id])} km/h" if t_id in self.spd else self.names[int(cls)]
        bbox_color = colors(int(t_id), True)

        annotator.box_label(box, speed_label, bbox_color)
        cv2.polylines(im0, [trk_pts], isClosed=False, color=bbox_color, thickness=self.tf)
        cv2.circle(im0, (int(track[-1][0]), int(track[-1][1])), self.tf * 2, bbox_color, -1)

        # Calculation of object speed
        if not self.reg_pts[0][0] < track[-1][0] < self.reg_pts[1][0]:
            return
        if self.reg_pts[1][1] - self.spdl < track[-1][1] < self.reg_pts[1][1] + self.spdl:
            direction = "known"
        elif self.reg_pts[0][1] - self.spdl < track[-1][1] < self.reg_pts[0][1] + self.spdl:
            direction = "known"
        else:
            direction = "unknown"

        if self.trk_pt.get(t_id) != 0 and direction != "unknown" and t_id not in self.trkd_ids:
            self.trkd_ids.append(t_id)

            time_difference = time() - self.trk_pt[t_id]
            if time_difference > 0:
                self.spd[t_id] = np.abs(track[-1][1] - self.trk_pp[t_id][1]) / time_difference

        self.trk_pt[t_id] = time()
        self.trk_pp[t_id] = track[-1]

    if self.view_img and self.env_check:
        cv2.imshow("Ultralytics Speed Estimation", im0)
        if cv2.waitKey(1) & 0xFF == ord("q"):
            return

    return im0




📅 Created 8 months ago ✏️ Updated 8 days ago