code: def _eval_seq_jde(
      self,
      dataloader,
      save_dir=None,
      show_image=False,
      frame_rate=30,
      draw_threshold=0,
  ):
      if save_dir:
          if not os.path.exists(save_dir):
              os.makedirs(save_dir)
      tracker = self.model.tracker
      tracker.max_time_lost = int(
          frame_rate / 30.0 * tracker.track_buffer
      )
  
      timer = Timer()
      results = []
      frame_id = 0
      self.status["mode"] = "track"
      self.model.eval()
      for step_id, data in enumerate(dataloader):
          # print('data', data)
          self.status["step_id"] = step_id
          if frame_id % 40 == 0:
              logger.info(
                  "Processing frame {} ({:.2f} fps)".format(
                      frame_id, 1.0 / max(1e-5, timer.average_time)
                  )
              )
  
          # forward
          timer.tic()
          pred_dets, pred_embs = self.model(data)
          online_targets = self.model.tracker.update(
              pred_dets, pred_embs
          )
          online_tlwhs, online_ids = [], []
          online_scores = []
          for t in online_targets:
              tlwh = t.tlwh
              tid = t.track_id
              tscore = t.score
              if tscore < draw_threshold:
                  continue
              vertical = tlwh[2] / tlwh[3] > 1.6
              if (
                  tlwh[2] * tlwh[3] > tracker.min_box_area
                  and not vertical
              ):
                  online_tlwhs.append(tlwh)
                  online_ids.append(tid)
                  online_scores.append(tscore)
          timer.toc()
  
          # save results
          results.append(
              (frame_id + 1, online_tlwhs, online_scores, online_ids)
          )
          self.save_results(
              data,
              frame_id,
              online_ids,
              online_tlwhs,
              online_scores,
              timer.average_time,
              show_image,
              save_dir,
          )
          frame_id += 1
  
      return results, frame_id, timer.average_time, timer.calls
  
imports: import os
  import cv2
  import glob
  import paddle
  import numpy
  import collections
  from ppdet.core.workspace import create
  from ppdet.utils.checkpoint import load_weight, load_pretrain_weight
  from ppdet.metrics import Metric, MOTMetric, KITTIMOTMetric
  import ppdet.utils.stats
  from ppdet.engine.callbacks import Callback, ComposeCallback
  from ppdet.utils.logger import setup_logger
  from .dataset import MOTVideoStream, MOTImageStream
  from .utils import Timer
  from .modeling.mot.utils import Detection, get_crops, scale_coords, clip_box
  from .modeling.mot import visualization
label_desc: Use image node_id 3 for calling the StreamTracker obj's underlying member method code with example usage: obj._eval_seq_jde(dataloader, save_dir, show_image, frame_rate, draw_threshold) and returns: results,  frame_id,  timer,  timer