Please use the recommended data structure as follows:
data
├── kaist01
│ ├── velodyne
│ | ├── .bin
| | └── ...
│ |── calib.txt
│ └── localization_poses01_seq02asmap.txt
└── kaist02
├── velodyne
| ├── .bin
| └── ...
|── calib.txt
└── localization_poses01_seq02asmap.txt