File size: 6,714 Bytes
53ad959
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
# Ultralytics YOLO 🚀, AGPL-3.0 license

from collections import defaultdict
from time import time

import cv2
import numpy as np

from ultralytics.utils.checks import check_imshow
from ultralytics.utils.plotting import Annotator, colors


class SpeedEstimator:
    """A class to estimation speed of objects in real-time video stream based on their tracks."""

    def __init__(self):
        """Initializes the speed-estimator class with default values for Visual, Image, track and speed parameters."""

        # Visual & im0 information
        self.im0 = None
        self.annotator = None
        self.view_img = False

        # Region information
        self.reg_pts = [(20, 400), (1260, 400)]
        self.region_thickness = 3

        # Predict/track information
        self.clss = None
        self.names = None
        self.boxes = None
        self.trk_ids = None
        self.trk_pts = None
        self.line_thickness = 2
        self.trk_history = defaultdict(list)

        # Speed estimator information
        self.current_time = 0
        self.dist_data = {}
        self.trk_idslist = []
        self.spdl_dist_thresh = 10
        self.trk_previous_times = {}
        self.trk_previous_points = {}

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

    def set_args(
        self,
        reg_pts,
        names,
        view_img=False,
        line_thickness=2,
        region_thickness=5,
        spdl_dist_thresh=10,
    ):
        """
        Configures the speed estimation and display parameters.

        Args:
            reg_pts (list): Initial list of points defining the speed calculation region.
            names (dict): object detection classes names
            view_img (bool): Flag indicating frame display
            line_thickness (int): Line thickness for bounding boxes.
            region_thickness (int): Speed estimation region thickness
            spdl_dist_thresh (int): Euclidean distance threshold for speed line
        """
        if reg_pts is None:
            print("Region points not provided, using default values")
        else:
            self.reg_pts = reg_pts
        self.names = names
        self.view_img = view_img
        self.line_thickness = line_thickness
        self.region_thickness = region_thickness
        self.spdl_dist_thresh = spdl_dist_thresh

    def extract_tracks(self, tracks):
        """
        Extracts results from the provided data.

        Args:
            tracks (list): List of tracks obtained from the object tracking process.
        """
        self.boxes = tracks[0].boxes.xyxy.cpu()
        self.clss = tracks[0].boxes.cls.cpu().tolist()
        self.trk_ids = tracks[0].boxes.id.int().cpu().tolist()

    def store_track_info(self, track_id, box):
        """
        Store track data.

        Args:
            track_id (int): object track id.
            box (list): object bounding box data
        """
        track = self.trk_history[track_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)

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

    def plot_box_and_track(self, track_id, box, cls, track):
        """
        Plot track and bounding box.

        Args:
            track_id (int): object track id.
            box (list): object bounding box data
            cls (str): object class name
            track (list): tracking history for tracks path drawing
        """
        speed_label = f"{int(self.dist_data[track_id])}km/ph" if track_id in self.dist_data else self.names[int(cls)]
        bbox_color = colors(int(track_id)) if track_id in self.dist_data else (255, 0, 255)

        self.annotator.box_label(box, speed_label, bbox_color)

        cv2.polylines(self.im0, [self.trk_pts], isClosed=False, color=(0, 255, 0), thickness=1)
        cv2.circle(self.im0, (int(track[-1][0]), int(track[-1][1])), 5, bbox_color, -1)

    def calculate_speed(self, trk_id, track):
        """
        Calculation of object speed.

        Args:
            trk_id (int): object track id.
            track (list): tracking history for tracks path drawing
        """

        if not self.reg_pts[0][0] < track[-1][0] < self.reg_pts[1][0]:
            return
        if self.reg_pts[1][1] - self.spdl_dist_thresh < track[-1][1] < self.reg_pts[1][1] + self.spdl_dist_thresh:
            direction = "known"

        elif self.reg_pts[0][1] - self.spdl_dist_thresh < track[-1][1] < self.reg_pts[0][1] + self.spdl_dist_thresh:
            direction = "known"

        else:
            direction = "unknown"

        if self.trk_previous_times[trk_id] != 0 and direction != "unknown" and trk_id not in self.trk_idslist:
            self.trk_idslist.append(trk_id)

            time_difference = time() - self.trk_previous_times[trk_id]
            if time_difference > 0:
                dist_difference = np.abs(track[-1][1] - self.trk_previous_points[trk_id][1])
                speed = dist_difference / time_difference
                self.dist_data[trk_id] = speed

        self.trk_previous_times[trk_id] = time()
        self.trk_previous_points[trk_id] = track[-1]

    def estimate_speed(self, im0, tracks, region_color=(255, 0, 0)):
        """
        Calculate object based on tracking data.

        Args:
            im0 (nd array): Image
            tracks (list): List of tracks obtained from the object tracking process.
            region_color (tuple): Color to use when drawing regions.
        """
        self.im0 = im0
        if tracks[0].boxes.id is None:
            if self.view_img and self.env_check:
                self.display_frames()
            return im0
        self.extract_tracks(tracks)

        self.annotator = Annotator(self.im0, line_width=2)
        self.annotator.draw_region(reg_pts=self.reg_pts, color=region_color, thickness=self.region_thickness)

        for box, trk_id, cls in zip(self.boxes, self.trk_ids, self.clss):
            track = self.store_track_info(trk_id, box)

            if trk_id not in self.trk_previous_times:
                self.trk_previous_times[trk_id] = 0

            self.plot_box_and_track(trk_id, box, cls, track)
            self.calculate_speed(trk_id, track)

        if self.view_img and self.env_check:
            self.display_frames()

        return im0

    def display_frames(self):
        """Display frame."""
        cv2.imshow("Ultralytics Speed Estimation", self.im0)
        if cv2.waitKey(1) & 0xFF == ord("q"):
            return


if __name__ == "__main__":
    SpeedEstimator()