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nerfstudio/nerfactory/cameras/rays.py
Ethan Weber 7e9a56fac4
Config restructure (#283)
* starting docs for pipelines

* working on an example

* clearing output

* starting to implement config changes and add documentation

* wip: removed cicular imports; porting basic config into python; todo: get python setups workin

* circular imports again

* wip: pausing at dataloader sort of working

* break for today

* running vanilla

* wip need to get all the config docs working

* laptop about to die

* instant ngp working

* added all configs for all methods; not tested yet: [mipnerf360, nerfw, semantic_nerf]

* unpacking later

* done with pylinting

* mostly done. just need to do docs and one test

* added import order to docs

* fixing near/far plane and other config things

* making loggers also instantiable via configs

* docs

* lint

* making --help work with dcargs

* moving configs back into flat

* convert list to tuples; fixed post init function with mutable params

* lint

* made run_eval and benchmarking scripts compatible with new config/dcargs

* lint

* added option to load configs from presaved config

Co-authored-by: evonneng <evonne_ng@berkeley.edu>
2022-08-26 17:25:10 -07:00

254 lines
8.7 KiB
Python

# Copyright 2022 The Plenoptix Team. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""
Some ray datastructures.
"""
import random
from dataclasses import dataclass
from typing import Optional
import torch
from torchtyping import TensorType
from nerfactory.utils.math import Gaussians, conical_frustum_to_gaussian
from nerfactory.utils.tensor_dataclass import TensorDataclass
@dataclass
class Frustums(TensorDataclass):
"""Describes region of space as a frustum.
Attributes:
origins: xyz coordinate for ray origin.
directions: Direction of ray.
starts: Where the frustum starts along a ray.
ends: Where the frustum ends along a ray.
pixel_area: Projected area of pixel a distance 1 away from origin.
"""
origins: TensorType["bs":..., 3]
directions: TensorType["bs":..., 3]
starts: TensorType["bs":..., 1]
ends: TensorType["bs":..., 1]
pixel_area: TensorType["bs":..., 1]
def get_positions(self) -> TensorType[..., 3]:
"""Calulates "center" position of frustum. Not weighted by mass.
Returns:
TensorType[..., 3]: xyz positions.
"""
return self.origins + self.directions * (self.starts + self.ends) / 2
def get_gaussian_blob(self) -> Gaussians:
"""Calculates of guassian approximation of conical frustum.
Resturns:
Gaussians: Conical frustums approximated by gaussian distribution.
"""
# Cone radius is set such that the square pixel_area matches the cone area.
cone_radius = torch.sqrt(self.pixel_area) / 1.7724538509055159 # r = sqrt(pixel_area / pi)
return conical_frustum_to_gaussian(
origins=self.origins,
directions=self.directions,
starts=self.starts,
ends=self.ends,
radius=cone_radius,
)
@classmethod
def get_mock_frustum(cls, device="cpu") -> "Frustums":
"""Helper function to generate a placeholder frustum.
Returns:
Frustums: A size 1 frustum with meaningless values.
"""
return Frustums(
origins=torch.ones((1, 3)).to(device),
directions=torch.ones((1, 3)).to(device),
starts=torch.ones((1, 1)).to(device),
ends=torch.ones((1, 1)).to(device),
pixel_area=torch.ones((1, 1)).to(device),
)
@dataclass
class RaySamples(TensorDataclass):
"""Samples along a ray
Args:
frustums: Frustums along ray.
camera_indices: Camera index.
valid_mask: Rays that are valid.
deltas: "width" of each sample.
ts: sample-camera distance of each sample.
"""
frustums: Frustums
camera_indices: Optional[TensorType["bs":..., 1]] = None
valid_mask: Optional[TensorType["bs":..., 1]] = None
deltas: Optional[TensorType["bs":..., 1]] = None
def get_weights(self, densities: TensorType[..., "num_samples", 1]) -> TensorType[..., "num_samples", 1]:
"""Return weights based on predicted densities
Args:
densities (TensorType[..., "num_samples", 1]): Predicted densities for samples along ray
Returns:
TensorType[..., "num_samples", 1]: Weights for each sample
"""
delta_density = self.deltas * densities
alphas = 1 - torch.exp(-delta_density)
# TODO: put both versions of the transmittance calculation somewhere
# mip-nerf version of transmittance calculation:
transmittance = torch.cumsum(delta_density[..., :-1, :], dim=-2)
transmittance = torch.cat(
[torch.zeros((*transmittance.shape[:1], 1, 1)).to(densities.device), transmittance], dim=-2
)
transmittance = torch.exp(-transmittance) # [..., "num_samples"]
# most nerf codebases do the following:
# transmittance = torch.cat(
# [torch.ones((*alphas.shape[:1], 1)).to(densities.device), 1.0 - alphas + 1e-10], dim=-1
# )
# transmittance = torch.cumprod(transmittance, dim=-1)[..., :-1] # [..., "num_samples"]
weights = alphas * transmittance # [..., "num_samples"]
return weights
def set_valid_mask(self, valid_mask: TensorType[..., "num_samples"]) -> None:
"""Sets valid mask"""
self.valid_mask = valid_mask
def apply_masks(self) -> "RaySamples":
"""Use valid_mask to mask samples.
Returns:
RaySamples: New set of masked samples.
"""
if self.valid_mask is not None:
return self[self.valid_mask[..., 0]]
return self
@dataclass
class RayBundle(TensorDataclass):
"""A bundle of ray parameters.
Args:
origins: Ray origins (XYZ)
directions: Unit ray direction vector
pixel_area: Projected area of pixel a distance 1 away from origin
camera_indices: Camera indices
nears: Distance along ray to start sampling
fars: Rays Distance along ray to stop sampling
valid_mask: Rays that are valid
num_rays_per_chunk: Number of rays per chunk
"""
# TODO(ethan): make sure the sizes with ... are correct
origins: TensorType[..., 3]
directions: TensorType[..., 3]
pixel_area: TensorType[..., 1]
camera_indices: Optional[TensorType[..., 1]] = None
nears: Optional[TensorType[..., 1]] = None
fars: Optional[TensorType[..., 1]] = None
valid_mask: Optional[TensorType[..., 1, bool]] = None
num_rays_per_chunk: int = 128
def set_camera_indices(self, camera_index: int) -> None:
"""Sets all of the the camera indices to a specific camera index.
Args:
camera_index (int): Camera index.
"""
self.camera_indices = torch.ones_like(self.origins[..., 0:1]).long() * camera_index
def __len__(self):
num_rays = torch.numel(self.origins) // self.origins.shape[-1]
return num_rays
def sample(self, num_rays: int) -> "RayBundle":
"""Returns a RayBundle as a subset of rays.
Args:
num_rays (int): Number of rays in output RayBundle
Returns:
RayBundle: RayBundle with subset of rays.
"""
assert num_rays <= len(self)
indices = random.sample(range(len(self)), k=num_rays)
return self[indices]
def get_row_major_sliced_ray_bundle(self, start_idx: int, end_idx: int) -> "RayBundle":
"""Flattens RayBundle and extracts chunk given start and end indicies.
Args:
start_idx (int): Start index of RayBundle chunk.
end_idx (int): End index of RayBundle chunk.
Returns:
RayBundle: Flattened RayBundle with end_idx-start_idx rays.
"""
return self.flatten()[start_idx:end_idx]
def get_ray_samples(
self, bin_starts: TensorType["bs":..., "num_samples", 1], bin_ends: TensorType["bs":..., "num_samples", 1]
) -> RaySamples:
"""Produces samples for each ray by projection points along the ray direction.
Args:
bin_starts (TensorType[..., "num_samples", 1]): Distance from origin to start of bin.
bin_ends (TensorType[..., "num_samples", 1]): Distance from origin to end of bin.
Returns:
RaySamples: Samples projected along ray.
"""
device = self.origins.device
valid_mask = torch.ones((bin_starts.shape), dtype=torch.bool, device=device)
dists = bin_ends - bin_starts # [..., N_samples, 1]
deltas = dists * torch.norm(self.directions[:, :], dim=-1)[..., None, None]
if self.camera_indices is not None:
camera_indices = self.camera_indices[..., None]
else:
camera_indices = None
frustums = Frustums(
origins=self.origins[..., None, :], # [..., 1, 3]
directions=self.directions[..., None, :], # [..., 1, 3]
starts=bin_starts, # [..., N_samples, 1]
ends=bin_ends, # [..., N_samples, 1]
pixel_area=self.pixel_area[..., None, :], # [..., 1, 1]
).to(device)
ray_samples = RaySamples(
frustums=frustums,
camera_indices=camera_indices, # [..., 1, 1]
valid_mask=valid_mask, # [..., N_samples, 1]
deltas=deltas, # [..., N_samples, 1]
)
return ray_samples