ACCAD MoCap "Frame Time" vs AMASS_ACAD "mocap_framerate"

nghorbani / amass

Data preparation and loader for AMASS

https://amass.is.tue.mpg.de/

Other

663 stars 87 forks source link

ACCAD MoCap "Frame Time" vs AMASS_ACAD "mocap_framerate" #8

Open glisca opened 4 years ago

glisca commented 4 years ago

Hi there,

I am looking at the files:

./Male2_bvh/Male2_B15_WalkTurnAround.bvh [1] from ACCAD dataset and
./ACCAD/Male2Walking_c3d/B15 - Walk turn around_poses.npz [2] from AMASS_ACCAD.

The Frame Time of [1] is 0.033 and the mocap_framerate of [2] is 120.0.

What is the meaning of the mocap_framerate entry of [2]?
How do you compute / choose the mocap_framerate entry of [2]

Thanks a lot!

kind regards,

nghorbani commented 4 years ago

Hello, the frame rate in AMASS npz files is copied directly from the original mocap sequences and it has use cases for video rendering of the file. I don't have concrete idea about 'frame time' of 0.033. it might be corresponding to downsampled framerate of 30 Hz, but then what is the count of frames in that bvh and the corresponding npz?

glisca commented 4 years ago

Hi,

I am looking at these files:

Male2_B15_WalkTurnAround.bvh from Male2_bvh.zip archive and it has:
- Frames: 207
- Frame Time: 0.0333333

and interpret it following this documentation and:

amass/ACCAD/Male2Walking_c3d/B15 - Walk turn around_poses.npz which has the dictionary entries:
- "mocap_framerate" = 120.0
- shape of "poses" = (901, 156)
- shape of "trans" = (901, 3)