About chi3d_smplx_test.h5

[JackYu6]

Hi, thanks for the code and data. By reading the chi3d_smplx_test.h5 through the following code:

with h5py.File(file_path, 'r') as f:
    for key in f.keys():
        print(f'{key}: {f[key].name}, Shape: {f[key].shape}')

I find the shape of every motion is [N, 56, 6]. Perhaps N represents the frame number of every motion. Then what do the last two numbers represent respectively? Are they about pose parameters, global orientation and the root translation? If so, what's the order of them. Hope to get your help, thanks.

[liangxuy]

The shape of motion data for each person is [N, 56, 3], thus for two persons, the motion shape is [N, 56, 6]. The details of the [56, 3] is illustrated here.

body_pose # [22, 3]
jaw_pose # [1, 3]
leye_pose # [1, 3]
reye_pose # [1, 3]
left_hand_pose # [15, 3]
right_hand_pose # [15, 3]
root_transl # [1, 3]

From body_pose to right_hand_pose are SMPLX-format rotational poses, and the last root_transl is the global trajectory of the person.

[JackYu6]

Thanks for your reply. I'm also curious to know why you directly use the SMPL-X parameters rather than the manually designed motion representation?

[liangxuy]

• Make-An-Animation: Large-Scale Text-conditional 3D Human Motion Generation (Sect. 3.1)
• Multi-Track Timeline Control for Text-Driven 3D Human Motion Generation

[JackYu6]

Really helpful. Thanks!