failed to get the output result

[mamianshusheng]

I ran this command:
vbench evaluate --videos_path "/home/notebook/code/group/hkx/video_tasks/dover/DOVER/demo" --dimension "motion_smoothness"

then it worked like this below:

args: Namespace(func=<function evaluate at 0x7fba11448f40>, output_path='./evaluation_results/', full_json_dir='./VBench_full_info.json', videos_path='/home/notebook/code/group/hkx/video_tasks/dover/DOVER/demo', dimension='motion_smoothness', load_ckpt_from_local=None, read_frame=None) start evaluation Evaluation meta data saved to ./evaluation_results/motion_smoothness_full_info.json Loading [networks.AMT-S.Model] from [/home/oppoer/.cache/vbench/amt_model/amt-s.pth]... 0it [00:00, ?it/s] /home/notebook/data/group/hkx/vbench/lib/python3.12/site-packages/numpy/core/fromnumeric.py:3504: RuntimeWarning: Mean of empty slice. return _methods._mean(a, axis=axis, dtype=dtype, /home/notebook/data/group/hkx/vbench/lib/python3.12/site-packages/numpy/core/_methods.py:129: RuntimeWarning: invalid value encountered in scalar divide ret = ret.dtype.type(ret / rcount) Evaluation results saved to ./evaluation_results/motion_smoothness_eval_results.json done

But I got this result in motion_smoothness_eval_results.json:

{ "motion_smoothness": [ NaN, [] ] }

can you tell me where is the problem?