gaussian-splatting/scene/gaussian_model.py
Stefan Saraev 18eb6d6a0c added support for setting floating point range
Users may want to reduce their memory consumption by using fp16.
However, in my tests, such attempts will result in lower quality renders.
Some data type conversions did not have any impact, so I removed them completely.
2024-05-15 22:29:23 +03:00

408 lines
19 KiB
Python

#
# Copyright (C) 2023, Inria
# GRAPHDECO research group, https://team.inria.fr/graphdeco
# All rights reserved.
#
# This software is free for non-commercial, research and evaluation use
# under the terms of the LICENSE.md file.
#
# For inquiries contact george.drettakis@inria.fr
#
import torch
import numpy as np
from utils.general_utils import inverse_sigmoid, get_expon_lr_func, build_rotation
from torch import nn
import os
from utils.system_utils import mkdir_p
from plyfile import PlyData, PlyElement
from utils.sh_utils import RGB2SH
from simple_knn._C import distCUDA2
from utils.graphics_utils import BasicPointCloud
from utils.general_utils import strip_symmetric, build_scaling_rotation
class GaussianModel:
def setup_functions(self, dtype):
def build_covariance_from_scaling_rotation(scaling, scaling_modifier, rotation):
L = build_scaling_rotation(scaling_modifier * scaling, rotation, dtype)
actual_covariance = L @ L.transpose(1, 2)
symm = strip_symmetric(actual_covariance, dtype)
return symm
self.scaling_activation = torch.exp
self.scaling_inverse_activation = torch.log
self.covariance_activation = build_covariance_from_scaling_rotation
self.opacity_activation = torch.sigmoid
self.inverse_opacity_activation = inverse_sigmoid
self.rotation_activation = torch.nn.functional.normalize
def __init__(self, sh_degree : int, dtype=torch.float32):
self.active_sh_degree = 0
self.max_sh_degree = sh_degree
self._xyz = torch.empty(0)
self._features_dc = torch.empty(0)
self._features_rest = torch.empty(0)
self._scaling = torch.empty(0)
self._rotation = torch.empty(0)
self._opacity = torch.empty(0)
self.max_radii2D = torch.empty(0)
self.xyz_gradient_accum = torch.empty(0)
self.denom = torch.empty(0)
self.optimizer = None
self.percent_dense = 0
self.spatial_lr_scale = 0
self.dtype = dtype
self.setup_functions(dtype)
def capture(self):
return (
self.active_sh_degree,
self._xyz,
self._features_dc,
self._features_rest,
self._scaling,
self._rotation,
self._opacity,
self.max_radii2D,
self.xyz_gradient_accum,
self.denom,
self.optimizer.state_dict(),
self.spatial_lr_scale,
)
def restore(self, model_args, training_args):
(self.active_sh_degree,
self._xyz,
self._features_dc,
self._features_rest,
self._scaling,
self._rotation,
self._opacity,
self.max_radii2D,
xyz_gradient_accum,
denom,
opt_dict,
self.spatial_lr_scale) = model_args
self.training_setup(training_args)
self.xyz_gradient_accum = xyz_gradient_accum
self.denom = denom
self.optimizer.load_state_dict(opt_dict)
@property
def get_scaling(self):
return self.scaling_activation(self._scaling)
@property
def get_rotation(self):
return self.rotation_activation(self._rotation)
@property
def get_xyz(self):
return self._xyz
@property
def get_features(self):
features_dc = self._features_dc
features_rest = self._features_rest
return torch.cat((features_dc, features_rest), dim=1)
@property
def get_opacity(self):
return self.opacity_activation(self._opacity)
def get_covariance(self, scaling_modifier = 1):
return self.covariance_activation(self.get_scaling, scaling_modifier, self._rotation)
def oneupSHdegree(self):
if self.active_sh_degree < self.max_sh_degree:
self.active_sh_degree += 1
def create_from_pcd(self, pcd : BasicPointCloud, spatial_lr_scale : float):
self.spatial_lr_scale = spatial_lr_scale
fused_point_cloud = torch.tensor(np.asarray(pcd.points)).float().cuda()
fused_color = RGB2SH(torch.tensor(np.asarray(pcd.colors)).float().cuda())
features = torch.zeros((fused_color.shape[0], 3, (self.max_sh_degree + 1) ** 2)).float().cuda()
features[:, :3, 0 ] = fused_color
features[:, 3:, 1:] = 0.0
print("Number of points at initialisation : ", fused_point_cloud.shape[0])
dist2 = torch.clamp_min(distCUDA2(torch.from_numpy(np.asarray(pcd.points)).float().cuda()), 0.0000001)
scales = torch.log(torch.sqrt(dist2))[...,None].repeat(1, 3)
rots = torch.zeros((fused_point_cloud.shape[0], 4), device="cuda")
rots[:, 0] = 1
opacities = inverse_sigmoid(0.1 * torch.ones((fused_point_cloud.shape[0], 1), dtype=self.dtype, device="cuda"))
self._xyz = nn.Parameter(fused_point_cloud.requires_grad_(True))
self._features_dc = nn.Parameter(features[:,:,0:1].transpose(1, 2).contiguous().requires_grad_(True))
self._features_rest = nn.Parameter(features[:,:,1:].transpose(1, 2).contiguous().requires_grad_(True))
self._scaling = nn.Parameter(scales.requires_grad_(True))
self._rotation = nn.Parameter(rots.requires_grad_(True))
self._opacity = nn.Parameter(opacities.requires_grad_(True))
self.max_radii2D = torch.zeros((self.get_xyz.shape[0]), device="cuda", dtype=self.dtype)
def training_setup(self, training_args):
self.percent_dense = training_args.percent_dense
self.xyz_gradient_accum = torch.zeros((self.get_xyz.shape[0], 1), device="cuda")
self.denom = torch.zeros((self.get_xyz.shape[0], 1), device="cuda")
l = [
{'params': [self._xyz], 'lr': training_args.position_lr_init * self.spatial_lr_scale, "name": "xyz"},
{'params': [self._features_dc], 'lr': training_args.feature_lr, "name": "f_dc"},
{'params': [self._features_rest], 'lr': training_args.feature_lr / 20.0, "name": "f_rest"},
{'params': [self._opacity], 'lr': training_args.opacity_lr, "name": "opacity"},
{'params': [self._scaling], 'lr': training_args.scaling_lr, "name": "scaling"},
{'params': [self._rotation], 'lr': training_args.rotation_lr, "name": "rotation"}
]
self.optimizer = torch.optim.Adam(l, lr=0.0, eps=1e-15)
self.xyz_scheduler_args = get_expon_lr_func(lr_init=training_args.position_lr_init*self.spatial_lr_scale,
lr_final=training_args.position_lr_final*self.spatial_lr_scale,
lr_delay_mult=training_args.position_lr_delay_mult,
max_steps=training_args.position_lr_max_steps)
def update_learning_rate(self, iteration):
''' Learning rate scheduling per step '''
for param_group in self.optimizer.param_groups:
if param_group["name"] == "xyz":
lr = self.xyz_scheduler_args(iteration)
param_group['lr'] = lr
return lr
def construct_list_of_attributes(self):
l = ['x', 'y', 'z', 'nx', 'ny', 'nz']
# All channels except the 3 DC
for i in range(self._features_dc.shape[1]*self._features_dc.shape[2]):
l.append('f_dc_{}'.format(i))
for i in range(self._features_rest.shape[1]*self._features_rest.shape[2]):
l.append('f_rest_{}'.format(i))
l.append('opacity')
for i in range(self._scaling.shape[1]):
l.append('scale_{}'.format(i))
for i in range(self._rotation.shape[1]):
l.append('rot_{}'.format(i))
return l
def save_ply(self, path):
mkdir_p(os.path.dirname(path))
xyz = self._xyz.detach().cpu().numpy()
normals = np.zeros_like(xyz)
f_dc = self._features_dc.detach().transpose(1, 2).flatten(start_dim=1).contiguous().cpu().numpy()
f_rest = self._features_rest.detach().transpose(1, 2).flatten(start_dim=1).contiguous().cpu().numpy()
opacities = self._opacity.detach().cpu().numpy()
scale = self._scaling.detach().cpu().numpy()
rotation = self._rotation.detach().cpu().numpy()
dtype_full = [(attribute, 'f4') for attribute in self.construct_list_of_attributes()]
elements = np.empty(xyz.shape[0], dtype=dtype_full)
attributes = np.concatenate((xyz, normals, f_dc, f_rest, opacities, scale, rotation), axis=1)
elements[:] = list(map(tuple, attributes))
el = PlyElement.describe(elements, 'vertex')
PlyData([el]).write(path)
def reset_opacity(self):
opacities_new = inverse_sigmoid(torch.min(self.get_opacity, torch.ones_like(self.get_opacity)*0.01))
optimizable_tensors = self.replace_tensor_to_optimizer(opacities_new, "opacity")
self._opacity = optimizable_tensors["opacity"]
def load_ply(self, path):
plydata = PlyData.read(path)
xyz = np.stack((np.asarray(plydata.elements[0]["x"]),
np.asarray(plydata.elements[0]["y"]),
np.asarray(plydata.elements[0]["z"])), axis=1)
opacities = np.asarray(plydata.elements[0]["opacity"])[..., np.newaxis]
features_dc = np.zeros((xyz.shape[0], 3, 1))
features_dc[:, 0, 0] = np.asarray(plydata.elements[0]["f_dc_0"])
features_dc[:, 1, 0] = np.asarray(plydata.elements[0]["f_dc_1"])
features_dc[:, 2, 0] = np.asarray(plydata.elements[0]["f_dc_2"])
extra_f_names = [p.name for p in plydata.elements[0].properties if p.name.startswith("f_rest_")]
extra_f_names = sorted(extra_f_names, key = lambda x: int(x.split('_')[-1]))
assert len(extra_f_names)==3*(self.max_sh_degree + 1) ** 2 - 3
features_extra = np.zeros((xyz.shape[0], len(extra_f_names)))
for idx, attr_name in enumerate(extra_f_names):
features_extra[:, idx] = np.asarray(plydata.elements[0][attr_name])
# Reshape (P,F*SH_coeffs) to (P, F, SH_coeffs except DC)
features_extra = features_extra.reshape((features_extra.shape[0], 3, (self.max_sh_degree + 1) ** 2 - 1))
scale_names = [p.name for p in plydata.elements[0].properties if p.name.startswith("scale_")]
scale_names = sorted(scale_names, key = lambda x: int(x.split('_')[-1]))
scales = np.zeros((xyz.shape[0], len(scale_names)))
for idx, attr_name in enumerate(scale_names):
scales[:, idx] = np.asarray(plydata.elements[0][attr_name])
rot_names = [p.name for p in plydata.elements[0].properties if p.name.startswith("rot")]
rot_names = sorted(rot_names, key = lambda x: int(x.split('_')[-1]))
rots = np.zeros((xyz.shape[0], len(rot_names)))
for idx, attr_name in enumerate(rot_names):
rots[:, idx] = np.asarray(plydata.elements[0][attr_name])
self._xyz = nn.Parameter(torch.tensor(xyz, dtype=self.dtype, device="cuda").requires_grad_(True))
self._features_dc = nn.Parameter(torch.tensor(features_dc, dtype=self.dtype, device="cuda").transpose(1, 2).contiguous().requires_grad_(True))
self._features_rest = nn.Parameter(torch.tensor(features_extra, dtype=self.dtype, device="cuda").transpose(1, 2).contiguous().requires_grad_(True))
self._opacity = nn.Parameter(torch.tensor(opacities, dtype=self.dtype, device="cuda").requires_grad_(True))
self._scaling = nn.Parameter(torch.tensor(scales, dtype=self.dtype, device="cuda").requires_grad_(True))
self._rotation = nn.Parameter(torch.tensor(rots, dtype=self.dtype, device="cuda").requires_grad_(True))
self.active_sh_degree = self.max_sh_degree
def replace_tensor_to_optimizer(self, tensor, name):
optimizable_tensors = {}
for group in self.optimizer.param_groups:
if group["name"] == name:
stored_state = self.optimizer.state.get(group['params'][0], None)
stored_state["exp_avg"] = torch.zeros_like(tensor)
stored_state["exp_avg_sq"] = torch.zeros_like(tensor)
del self.optimizer.state[group['params'][0]]
group["params"][0] = nn.Parameter(tensor.requires_grad_(True))
self.optimizer.state[group['params'][0]] = stored_state
optimizable_tensors[group["name"]] = group["params"][0]
return optimizable_tensors
def _prune_optimizer(self, mask):
optimizable_tensors = {}
for group in self.optimizer.param_groups:
stored_state = self.optimizer.state.get(group['params'][0], None)
if stored_state is not None:
stored_state["exp_avg"] = stored_state["exp_avg"][mask]
stored_state["exp_avg_sq"] = stored_state["exp_avg_sq"][mask]
del self.optimizer.state[group['params'][0]]
group["params"][0] = nn.Parameter((group["params"][0][mask].requires_grad_(True)))
self.optimizer.state[group['params'][0]] = stored_state
optimizable_tensors[group["name"]] = group["params"][0]
else:
group["params"][0] = nn.Parameter(group["params"][0][mask].requires_grad_(True))
optimizable_tensors[group["name"]] = group["params"][0]
return optimizable_tensors
def prune_points(self, mask):
valid_points_mask = ~mask
optimizable_tensors = self._prune_optimizer(valid_points_mask)
self._xyz = optimizable_tensors["xyz"]
self._features_dc = optimizable_tensors["f_dc"]
self._features_rest = optimizable_tensors["f_rest"]
self._opacity = optimizable_tensors["opacity"]
self._scaling = optimizable_tensors["scaling"]
self._rotation = optimizable_tensors["rotation"]
self.xyz_gradient_accum = self.xyz_gradient_accum[valid_points_mask]
self.denom = self.denom[valid_points_mask]
self.max_radii2D = self.max_radii2D[valid_points_mask]
def cat_tensors_to_optimizer(self, tensors_dict):
optimizable_tensors = {}
for group in self.optimizer.param_groups:
assert len(group["params"]) == 1
extension_tensor = tensors_dict[group["name"]]
stored_state = self.optimizer.state.get(group['params'][0], None)
if stored_state is not None:
stored_state["exp_avg"] = torch.cat((stored_state["exp_avg"], torch.zeros_like(extension_tensor)), dim=0)
stored_state["exp_avg_sq"] = torch.cat((stored_state["exp_avg_sq"], torch.zeros_like(extension_tensor)), dim=0)
del self.optimizer.state[group['params'][0]]
group["params"][0] = nn.Parameter(torch.cat((group["params"][0], extension_tensor), dim=0).requires_grad_(True))
self.optimizer.state[group['params'][0]] = stored_state
optimizable_tensors[group["name"]] = group["params"][0]
else:
group["params"][0] = nn.Parameter(torch.cat((group["params"][0], extension_tensor), dim=0).requires_grad_(True))
optimizable_tensors[group["name"]] = group["params"][0]
return optimizable_tensors
def densification_postfix(self, new_xyz, new_features_dc, new_features_rest, new_opacities, new_scaling, new_rotation):
d = {"xyz": new_xyz,
"f_dc": new_features_dc,
"f_rest": new_features_rest,
"opacity": new_opacities,
"scaling" : new_scaling,
"rotation" : new_rotation}
optimizable_tensors = self.cat_tensors_to_optimizer(d)
self._xyz = optimizable_tensors["xyz"]
self._features_dc = optimizable_tensors["f_dc"]
self._features_rest = optimizable_tensors["f_rest"]
self._opacity = optimizable_tensors["opacity"]
self._scaling = optimizable_tensors["scaling"]
self._rotation = optimizable_tensors["rotation"]
self.xyz_gradient_accum = torch.zeros((self.get_xyz.shape[0], 1), device="cuda")
self.denom = torch.zeros((self.get_xyz.shape[0], 1), device="cuda")
self.max_radii2D = torch.zeros((self.get_xyz.shape[0]), device="cuda")
def densify_and_split(self, grads, grad_threshold, scene_extent, N=2):
n_init_points = self.get_xyz.shape[0]
# Extract points that satisfy the gradient condition
padded_grad = torch.zeros((n_init_points), device="cuda")
padded_grad[:grads.shape[0]] = grads.squeeze()
selected_pts_mask = torch.where(padded_grad >= grad_threshold, True, False)
selected_pts_mask = torch.logical_and(selected_pts_mask,
torch.max(self.get_scaling, dim=1).values > self.percent_dense*scene_extent)
stds = self.get_scaling[selected_pts_mask].repeat(N,1)
means =torch.zeros((stds.size(0), 3),device="cuda")
samples = torch.normal(mean=means, std=stds)
rots = build_rotation(self._rotation[selected_pts_mask]).repeat(N,1,1)
new_xyz = torch.bmm(rots, samples.unsqueeze(-1)).squeeze(-1) + self.get_xyz[selected_pts_mask].repeat(N, 1)
new_scaling = self.scaling_inverse_activation(self.get_scaling[selected_pts_mask].repeat(N,1) / (0.8*N))
new_rotation = self._rotation[selected_pts_mask].repeat(N,1)
new_features_dc = self._features_dc[selected_pts_mask].repeat(N,1,1)
new_features_rest = self._features_rest[selected_pts_mask].repeat(N,1,1)
new_opacity = self._opacity[selected_pts_mask].repeat(N,1)
self.densification_postfix(new_xyz, new_features_dc, new_features_rest, new_opacity, new_scaling, new_rotation)
prune_filter = torch.cat((selected_pts_mask, torch.zeros(N * selected_pts_mask.sum(), device="cuda", dtype=bool)))
self.prune_points(prune_filter)
def densify_and_clone(self, grads, grad_threshold, scene_extent):
# Extract points that satisfy the gradient condition
selected_pts_mask = torch.where(torch.norm(grads, dim=-1) >= grad_threshold, True, False)
selected_pts_mask = torch.logical_and(selected_pts_mask,
torch.max(self.get_scaling, dim=1).values <= self.percent_dense*scene_extent)
new_xyz = self._xyz[selected_pts_mask]
new_features_dc = self._features_dc[selected_pts_mask]
new_features_rest = self._features_rest[selected_pts_mask]
new_opacities = self._opacity[selected_pts_mask]
new_scaling = self._scaling[selected_pts_mask]
new_rotation = self._rotation[selected_pts_mask]
self.densification_postfix(new_xyz, new_features_dc, new_features_rest, new_opacities, new_scaling, new_rotation)
def densify_and_prune(self, max_grad, min_opacity, extent, max_screen_size):
grads = self.xyz_gradient_accum / self.denom
grads[grads.isnan()] = 0.0
self.densify_and_clone(grads, max_grad, extent)
self.densify_and_split(grads, max_grad, extent)
prune_mask = (self.get_opacity < min_opacity).squeeze()
if max_screen_size:
big_points_vs = self.max_radii2D > max_screen_size
big_points_ws = self.get_scaling.max(dim=1).values > 0.1 * extent
prune_mask = torch.logical_or(torch.logical_or(prune_mask, big_points_vs), big_points_ws)
self.prune_points(prune_mask)
torch.cuda.empty_cache()
def add_densification_stats(self, viewspace_point_tensor, update_filter):
self.xyz_gradient_accum[update_filter] += torch.norm(viewspace_point_tensor.grad[update_filter,:2], dim=-1, keepdim=True)
self.denom[update_filter] += 1