DreamCraft3D/threestudio/models/networks.py
2023-12-15 17:44:44 +08:00

411 lines
15 KiB
Python

import math
import tinycudann as tcnn
import torch
import torch.nn as nn
import torch.nn.functional as F
import threestudio
from threestudio.utils.base import Updateable
from threestudio.utils.config import config_to_primitive
from threestudio.utils.misc import get_rank
from threestudio.utils.ops import get_activation
from threestudio.utils.typing import *
class ProgressiveBandFrequency(nn.Module, Updateable):
def __init__(self, in_channels: int, config: dict):
super().__init__()
self.N_freqs = config["n_frequencies"]
self.in_channels, self.n_input_dims = in_channels, in_channels
self.funcs = [torch.sin, torch.cos]
self.freq_bands = 2 ** torch.linspace(0, self.N_freqs - 1, self.N_freqs)
self.n_output_dims = self.in_channels * (len(self.funcs) * self.N_freqs)
self.n_masking_step = config.get("n_masking_step", 0)
self.update_step(
None, None
) # mask should be updated at the beginning each step
def forward(self, x):
out = []
for freq, mask in zip(self.freq_bands, self.mask):
for func in self.funcs:
out += [func(freq * x) * mask]
return torch.cat(out, -1)
def update_step(self, epoch, global_step, on_load_weights=False):
if self.n_masking_step <= 0 or global_step is None:
self.mask = torch.ones(self.N_freqs, dtype=torch.float32)
else:
self.mask = (
1.0
- torch.cos(
math.pi
* (
global_step / self.n_masking_step * self.N_freqs
- torch.arange(0, self.N_freqs)
).clamp(0, 1)
)
) / 2.0
threestudio.debug(
f"Update mask: {global_step}/{self.n_masking_step} {self.mask}"
)
class TCNNEncoding(nn.Module):
def __init__(self, in_channels, config, dtype=torch.float32) -> None:
super().__init__()
self.n_input_dims = in_channels
with torch.cuda.device(get_rank()):
self.encoding = tcnn.Encoding(in_channels, config, dtype=dtype)
self.n_output_dims = self.encoding.n_output_dims
def forward(self, x):
return self.encoding(x)
# 4D implicit decomposition of space and time (4D-fy)
class TCNNEncodingSpatialTime(nn.Module):
def __init__(
self, in_channels, config, dtype=torch.float32, init_time_zero=False
) -> None:
super().__init__()
self.n_input_dims = in_channels
config["otype"] = "HashGrid"
self.num_frames = 1 # config["num_frames"]
self.static = config["static"]
self.cfg = config_to_primitive(config)
self.cfg_time = self.cfg
self.n_key_frames = config.get("n_key_frames", 1)
with torch.cuda.device(get_rank()):
self.encoding = tcnn.Encoding(self.n_input_dims, self.cfg, dtype=dtype)
self.encoding_time = tcnn.Encoding(
self.n_input_dims + 1, self.cfg_time, dtype=dtype
)
self.n_output_dims = self.encoding.n_output_dims
self.frame_time = None
if self.static:
self.set_temp_param_grad(requires_grad=False)
self.use_key_frame = config.get("use_key_frame", False)
self.is_video = True
self.update_occ_grid = False
def set_temp_param_grad(self, requires_grad=False):
self.set_param_grad(self.encoding_time, requires_grad=requires_grad)
def set_param_grad(self, param_list, requires_grad=False):
if isinstance(param_list, nn.Parameter):
param_list.requires_grad = requires_grad
else:
for param in param_list.parameters():
param.requires_grad = requires_grad
def forward(self, x):
# TODO frame_time only supports batch_size == 1 cases
if self.update_occ_grid and not isinstance(self.frame_time, float):
frame_time = self.frame_time
else:
if (self.static or not self.training) and self.frame_time is None:
frame_time = torch.zeros(
(self.num_frames, 1), device=x.device, dtype=x.dtype
).expand(x.shape[0], 1)
else:
if self.frame_time is None:
frame_time = 0.0
else:
frame_time = self.frame_time
frame_time = (
torch.ones((self.num_frames, 1), device=x.device, dtype=x.dtype)
* frame_time
).expand(x.shape[0], 1)
frame_time = frame_time.view(-1, 1)
enc_space = self.encoding(x)
x_frame_time = torch.cat((x, frame_time), 1)
enc_space_time = self.encoding_time(x_frame_time)
enc = enc_space + enc_space_time
return enc
class ProgressiveBandHashGrid(nn.Module, Updateable):
def __init__(self, in_channels, config, dtype=torch.float32):
super().__init__()
self.n_input_dims = in_channels
encoding_config = config.copy()
encoding_config["otype"] = "Grid"
encoding_config["type"] = "Hash"
with torch.cuda.device(get_rank()):
self.encoding = tcnn.Encoding(in_channels, encoding_config, dtype=dtype)
self.n_output_dims = self.encoding.n_output_dims
self.n_level = config["n_levels"]
self.n_features_per_level = config["n_features_per_level"]
self.start_level, self.start_step, self.update_steps = (
config["start_level"],
config["start_step"],
config["update_steps"],
)
self.current_level = self.start_level
self.mask = torch.zeros(
self.n_level * self.n_features_per_level,
dtype=torch.float32,
device=get_rank(),
)
def forward(self, x):
enc = self.encoding(x)
enc = enc * self.mask
return enc
def update_step(self, epoch, global_step, on_load_weights=False):
current_level = min(
self.start_level
+ max(global_step - self.start_step, 0) // self.update_steps,
self.n_level,
)
if current_level > self.current_level:
threestudio.debug(f"Update current level to {current_level}")
self.current_level = current_level
self.mask[: self.current_level * self.n_features_per_level] = 1.0
class CompositeEncoding(nn.Module, Updateable):
def __init__(self, encoding, include_xyz=False, xyz_scale=2.0, xyz_offset=-1.0):
super(CompositeEncoding, self).__init__()
self.encoding = encoding
self.include_xyz, self.xyz_scale, self.xyz_offset = (
include_xyz,
xyz_scale,
xyz_offset,
)
self.n_output_dims = (
int(self.include_xyz) * self.encoding.n_input_dims
+ self.encoding.n_output_dims
)
def forward(self, x, *args):
return (
self.encoding(x, *args)
if not self.include_xyz
else torch.cat(
[x * self.xyz_scale + self.xyz_offset, self.encoding(x, *args)], dim=-1
)
)
def get_encoding(n_input_dims: int, config) -> nn.Module:
# input suppose to be range [0, 1]
encoding: nn.Module
if config.otype == "ProgressiveBandFrequency":
encoding = ProgressiveBandFrequency(n_input_dims, config_to_primitive(config))
elif config.otype == "ProgressiveBandHashGrid":
encoding = ProgressiveBandHashGrid(n_input_dims, config_to_primitive(config))
elif config.otype == "HashGridSpatialTime":
encoding = TCNNEncodingSpatialTime(n_input_dims, config) # 4D-fy encoding
else:
encoding = TCNNEncoding(n_input_dims, config_to_primitive(config))
encoding = CompositeEncoding(
encoding,
include_xyz=config.get("include_xyz", False),
xyz_scale=2.0,
xyz_offset=-1.0,
) # FIXME: hard coded
return encoding
class VanillaMLP(nn.Module):
def __init__(self, dim_in: int, dim_out: int, config: dict):
super().__init__()
self.n_neurons, self.n_hidden_layers = (
config["n_neurons"],
config["n_hidden_layers"],
)
layers = [
self.make_linear(dim_in, self.n_neurons, is_first=True, is_last=False),
self.make_activation(),
]
for i in range(self.n_hidden_layers - 1):
layers += [
self.make_linear(
self.n_neurons, self.n_neurons, is_first=False, is_last=False
),
self.make_activation(),
]
layers += [
self.make_linear(self.n_neurons, dim_out, is_first=False, is_last=True)
]
self.layers = nn.Sequential(*layers)
self.output_activation = get_activation(config.get("output_activation", None))
def forward(self, x):
# disable autocast
# strange that the parameters will have empty gradients if autocast is enabled in AMP
with torch.cuda.amp.autocast(enabled=False):
x = self.layers(x)
x = self.output_activation(x)
return x
def make_linear(self, dim_in, dim_out, is_first, is_last):
layer = nn.Linear(dim_in, dim_out, bias=False)
return layer
def make_activation(self):
return nn.ReLU(inplace=True)
class SphereInitVanillaMLP(nn.Module):
def __init__(self, dim_in, dim_out, config):
super().__init__()
self.n_neurons, self.n_hidden_layers = (
config["n_neurons"],
config["n_hidden_layers"],
)
self.sphere_init, self.weight_norm = True, True
self.sphere_init_radius = config["sphere_init_radius"]
self.sphere_init_inside_out = config["inside_out"]
self.layers = [
self.make_linear(dim_in, self.n_neurons, is_first=True, is_last=False),
self.make_activation(),
]
for i in range(self.n_hidden_layers - 1):
self.layers += [
self.make_linear(
self.n_neurons, self.n_neurons, is_first=False, is_last=False
),
self.make_activation(),
]
self.layers += [
self.make_linear(self.n_neurons, dim_out, is_first=False, is_last=True)
]
self.layers = nn.Sequential(*self.layers)
self.output_activation = get_activation(config.get("output_activation", None))
def forward(self, x):
# disable autocast
# strange that the parameters will have empty gradients if autocast is enabled in AMP
with torch.cuda.amp.autocast(enabled=False):
x = self.layers(x)
x = self.output_activation(x)
return x
def make_linear(self, dim_in, dim_out, is_first, is_last):
layer = nn.Linear(dim_in, dim_out, bias=True)
if is_last:
if not self.sphere_init_inside_out:
torch.nn.init.constant_(layer.bias, -self.sphere_init_radius)
torch.nn.init.normal_(
layer.weight,
mean=math.sqrt(math.pi) / math.sqrt(dim_in),
std=0.0001,
)
else:
torch.nn.init.constant_(layer.bias, self.sphere_init_radius)
torch.nn.init.normal_(
layer.weight,
mean=-math.sqrt(math.pi) / math.sqrt(dim_in),
std=0.0001,
)
elif is_first:
torch.nn.init.constant_(layer.bias, 0.0)
torch.nn.init.constant_(layer.weight[:, 3:], 0.0)
torch.nn.init.normal_(
layer.weight[:, :3], 0.0, math.sqrt(2) / math.sqrt(dim_out)
)
else:
torch.nn.init.constant_(layer.bias, 0.0)
torch.nn.init.normal_(layer.weight, 0.0, math.sqrt(2) / math.sqrt(dim_out))
if self.weight_norm:
layer = nn.utils.weight_norm(layer)
return layer
def make_activation(self):
return nn.Softplus(beta=100)
class TCNNNetwork(nn.Module):
def __init__(self, dim_in: int, dim_out: int, config: dict) -> None:
super().__init__()
with torch.cuda.device(get_rank()):
self.network = tcnn.Network(dim_in, dim_out, config)
def forward(self, x):
return self.network(x).float() # transform to float32
def get_mlp(n_input_dims, n_output_dims, config) -> nn.Module:
network: nn.Module
if config.otype == "VanillaMLP":
network = VanillaMLP(n_input_dims, n_output_dims, config_to_primitive(config))
elif config.otype == "SphereInitVanillaMLP":
network = SphereInitVanillaMLP(
n_input_dims, n_output_dims, config_to_primitive(config)
)
else:
assert (
config.get("sphere_init", False) is False
), "sphere_init=True only supported by VanillaMLP"
network = TCNNNetwork(n_input_dims, n_output_dims, config_to_primitive(config))
return network
class NetworkWithInputEncoding(nn.Module, Updateable):
def __init__(self, encoding, network):
super().__init__()
self.encoding, self.network = encoding, network
def forward(self, x):
return self.network(self.encoding(x))
class TCNNNetworkWithInputEncoding(nn.Module):
def __init__(
self,
n_input_dims: int,
n_output_dims: int,
encoding_config: dict,
network_config: dict,
) -> None:
super().__init__()
with torch.cuda.device(get_rank()):
self.network_with_input_encoding = tcnn.NetworkWithInputEncoding(
n_input_dims=n_input_dims,
n_output_dims=n_output_dims,
encoding_config=encoding_config,
network_config=network_config,
)
def forward(self, x):
return self.network_with_input_encoding(x).float() # transform to float32
def create_network_with_input_encoding(
n_input_dims: int, n_output_dims: int, encoding_config, network_config
) -> nn.Module:
# input suppose to be range [0, 1]
network_with_input_encoding: nn.Module
if encoding_config.otype in [
"VanillaFrequency",
"ProgressiveBandHashGrid",
] or network_config.otype in ["VanillaMLP", "SphereInitVanillaMLP"]:
encoding = get_encoding(n_input_dims, encoding_config)
network = get_mlp(encoding.n_output_dims, n_output_dims, network_config)
network_with_input_encoding = NetworkWithInputEncoding(encoding, network)
else:
network_with_input_encoding = TCNNNetworkWithInputEncoding(
n_input_dims=n_input_dims,
n_output_dims=n_output_dims,
encoding_config=config_to_primitive(encoding_config),
network_config=config_to_primitive(network_config),
)
return network_with_input_encoding
class ToDTypeWrapper(nn.Module):
def __init__(self, module: nn.Module, dtype: torch.dtype):
super().__init__()
self.module = module
self.dtype = dtype
def forward(self, x: Float[Tensor, "..."]) -> Float[Tensor, "..."]:
return self.module(x).to(self.dtype)