获取sample
self.samples = [samp for samp in self.nusc.sample if self.nusc.get('scene', samp['scene_token'])['name'] in scenes]
rec = self.samples[idx]
1. 获取当前帧数据
- 获取当前帧环视图像：
self.cam_keys = ['CAM_FRONT_LEFT', 'CAM_FRONT', 'CAM_FRONT_RIGHT', 'CAM_BACK_RIGHT', 'CAM_BACK', 'CAM_BACK_LEFT']
sample_path = []
for cam_key in self.cam_keys:
samp = self.nusc.get('sample_data', rec['data'][cam_key])
cam_path = samp['filename']
sample_path.append(cam_path)
- 获取当前帧
ego pose：
ego_pose = self.nusc.get('ego_pose', self.nusc.get('sample_data', rec['data']['CAM_FRONT'])['ego_pose_token'])
2. 获取前一帧或后一帧帧数据
关键字：前一帧为'prev'，后一帧为'next'。
- 获取前一帧环视图像：
self.cam_keys = ['CAM_FRONT_LEFT', 'CAM_FRONT', 'CAM_FRONT_RIGHT', 'CAM_BACK_RIGHT', 'CAM_BACK', 'CAM_BACK_LEFT']
sample_path = []
for cam_key in self.cam_keys:
last_samp = self.nusc.get('sample_data',samp['prev']) # 获取前一帧的sample
lst_cam_path = last_samp['filename']
lst_sample_path.append(lst_cam_path)
- 获取前一帧
ego pose：
if samp['prev'] == '':
last_ego_pose = ego_pose # 如果没有前一帧，则保持不变
else:
last_ego_pose = self.nusc.get('ego_pose', self.nusc.get('sample_data', rec['data']['CAM_FRONT'])['prev'])
前一帧和后一帧的ego_pose
