|
import torch |
|
import torch.nn as nn |
|
|
|
from . import functional as F |
|
|
|
__all__ = ['Voxelization'] |
|
|
|
|
|
def my_voxelization(features, coords, resolution): |
|
b, c, _ = features.shape |
|
result = torch.zeros(b, c + 1, resolution * resolution * resolution, device=features.device, dtype=features.dtype) |
|
r = resolution |
|
r2 = resolution * resolution |
|
coords = coords.long() |
|
indices = coords[:, 0] * r2 + coords[:, 1] * r + coords[:, 2] |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
indices = indices.unsqueeze(dim=1).expand(-1, result.shape[1], -1) |
|
features = torch.cat([features, torch.ones(features.shape[0], 1, features.shape[2], device=features.device, dtype=features.dtype)], dim=1) |
|
out_feature = result.scatter_(index=indices.long(), src=features, dim=2, reduce='add') |
|
cnt = out_feature[:, -1:, :] |
|
zero_mask = (cnt == 0).to(features.dtype) |
|
cnt = cnt * (1 - zero_mask) + zero_mask * 1e-5 |
|
vox_feature = out_feature[:, :-1, :] / cnt |
|
return vox_feature.view(b, c, resolution, resolution, resolution) |
|
|
|
class Voxelization(nn.Module): |
|
def __init__(self, resolution, normalize=True, eps=0, scale_pvcnn=False): |
|
super().__init__() |
|
self.r = int(resolution) |
|
self.normalize = normalize |
|
self.eps = eps |
|
self.scale_pvcnn = scale_pvcnn |
|
assert not normalize |
|
|
|
def forward(self, features, coords): |
|
|
|
with torch.no_grad(): |
|
coords = coords.detach() |
|
|
|
if self.normalize: |
|
norm_coords = norm_coords / (norm_coords.norm(dim=1, keepdim=True).max(dim=2, keepdim=True).values * 2.0 + self.eps) + 0.5 |
|
else: |
|
if self.scale_pvcnn: |
|
norm_coords = (coords + 1) / 2.0 |
|
|
|
else: |
|
|
|
norm_coords = (coords + 1) / 2.0 |
|
norm_coords = torch.clamp(norm_coords * self.r, 0, self.r - 1) |
|
|
|
vox_coords = torch.round(norm_coords) |
|
|
|
|
|
new_vox_feat = my_voxelization(features, vox_coords, self.r) |
|
return new_vox_feat, norm_coords |
|
|
|
def extra_repr(self): |
|
return 'resolution={}{}'.format(self.r, ', normalized eps = {}'.format(self.eps) if self.normalize else '') |
|
|