Spaces:
Runtime error
Runtime error
import numpy as np | |
import torch | |
from scipy.spatial.transform import Rotation as RotLib | |
def SO3_to_quat(R): | |
""" | |
:param R: (N, 3, 3) or (3, 3) np | |
:return: (N, 4, ) or (4, ) np | |
""" | |
x = RotLib.from_matrix(R) | |
quat = x.as_quat() | |
return quat | |
def quat_to_SO3(quat): | |
""" | |
:param quat: (N, 4, ) or (4, ) np | |
:return: (N, 3, 3) or (3, 3) np | |
""" | |
x = RotLib.from_quat(quat) | |
R = x.as_matrix() | |
return R | |
def convert3x4_4x4(input): | |
""" | |
:param input: (N, 3, 4) or (3, 4) torch or np | |
:return: (N, 4, 4) or (4, 4) torch or np | |
""" | |
if torch.is_tensor(input): | |
if len(input.shape) == 3: | |
output = torch.cat([input, torch.zeros_like(input[:, 0:1])], dim=1) # (N, 4, 4) | |
output[:, 3, 3] = 1.0 | |
else: | |
output = torch.cat([input, torch.tensor([[0,0,0,1]], dtype=input.dtype, device=input.device)], dim=0) # (4, 4) | |
else: | |
if len(input.shape) == 3: | |
output = np.concatenate([input, np.zeros_like(input[:, 0:1])], axis=1) # (N, 4, 4) | |
output[:, 3, 3] = 1.0 | |
else: | |
output = np.concatenate([input, np.array([[0,0,0,1]], dtype=input.dtype)], axis=0) # (4, 4) | |
output[3, 3] = 1.0 | |
return output | |
def vec2skew(v): | |
""" | |
:param v: (3, ) torch tensor | |
:return: (3, 3) | |
""" | |
zero = torch.zeros(1, dtype=torch.float32, device=v.device) | |
skew_v0 = torch.cat([ zero, -v[2:3], v[1:2]]) # (3, 1) | |
skew_v1 = torch.cat([ v[2:3], zero, -v[0:1]]) | |
skew_v2 = torch.cat([-v[1:2], v[0:1], zero]) | |
skew_v = torch.stack([skew_v0, skew_v1, skew_v2], dim=0) # (3, 3) | |
return skew_v # (3, 3) | |
def Exp(r): | |
"""so(3) vector to SO(3) matrix | |
:param r: (3, ) axis-angle, torch tensor | |
:return: (3, 3) | |
""" | |
skew_r = vec2skew(r) # (3, 3) | |
norm_r = r.norm() + 1e-15 | |
eye = torch.eye(3, dtype=torch.float32, device=r.device) | |
R = eye + (torch.sin(norm_r) / norm_r) * skew_r + ((1 - torch.cos(norm_r)) / norm_r**2) * (skew_r @ skew_r) | |
return R | |
def make_c2w(r, t): | |
""" | |
:param r: (3, ) axis-angle torch tensor | |
:param t: (3, ) translation vector torch tensor | |
:return: (4, 4) | |
""" | |
R = Exp(r) # (3, 3) | |
c2w = torch.cat([R, t.unsqueeze(1)], dim=1) # (3, 4) | |
c2w = convert3x4_4x4(c2w) # (4, 4) | |
return c2w | |