| 145 | |
| 146 | |
| 147 | class BYTETracker(object): |
| 148 | def __init__(self, frame_rate=30): |
| 149 | self.tracked_stracks = [] # type: list[STrack] |
| 150 | self.lost_stracks = [] # type: list[STrack] |
| 151 | self.removed_stracks = [] # type: list[STrack] |
| 152 | |
| 153 | self.frame_id = 0 |
| 154 | |
| 155 | self.low_thresh = 0.2 |
| 156 | self.track_thresh = 0.8 |
| 157 | self.det_thresh = self.track_thresh + 0.1 |
| 158 | |
| 159 | |
| 160 | self.buffer_size = int(frame_rate / 30.0 * 30) |
| 161 | self.max_time_lost = self.buffer_size |
| 162 | self.kalman_filter = KalmanFilter() |
| 163 | |
| 164 | def update(self, output_results): |
| 165 | self.frame_id += 1 |
| 166 | activated_starcks = [] |
| 167 | refind_stracks = [] |
| 168 | lost_stracks = [] |
| 169 | removed_stracks = [] |
| 170 | |
| 171 | |
| 172 | scores = output_results[:, 4] |
| 173 | bboxes = output_results[:, :4] # x1y1x2y2 |
| 174 | |
| 175 | remain_inds = scores > self.track_thresh |
| 176 | dets = bboxes[remain_inds] |
| 177 | scores_keep = scores[remain_inds] |
| 178 | |
| 179 | |
| 180 | inds_low = scores > self.low_thresh |
| 181 | inds_high = scores < self.track_thresh |
| 182 | inds_second = np.logical_and(inds_low, inds_high) |
| 183 | dets_second = bboxes[inds_second] |
| 184 | scores_second = scores[inds_second] |
| 185 | |
| 186 | |
| 187 | if len(dets) > 0: |
| 188 | '''Detections''' |
| 189 | detections = [STrack(STrack.tlbr_to_tlwh(tlbr), s) for |
| 190 | (tlbr, s) in zip(dets, scores_keep)] |
| 191 | else: |
| 192 | detections = [] |
| 193 | |
| 194 | ''' Add newly detected tracklets to tracked_stracks''' |
| 195 | unconfirmed = [] |
| 196 | tracked_stracks = [] # type: list[STrack] |
| 197 | for track in self.tracked_stracks: |
| 198 | if not track.is_activated: |
| 199 | unconfirmed.append(track) |
| 200 | else: |
| 201 | tracked_stracks.append(track) |
| 202 | |
| 203 | ''' Step 2: First association, with Kalman and IOU''' |
| 204 | strack_pool = joint_stracks(tracked_stracks, self.lost_stracks) |