File size: 16,978 Bytes
938e515 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 |
# Copyright (c) Facebook, Inc. and its affiliates.
import math
from functools import lru_cache
import torch
from torch import nn
from torch.autograd import Function
from torch.autograd.function import once_differentiable
from torch.nn.modules.utils import _pair
from torchvision.ops import deform_conv2d
from detectron2.utils.develop import create_dummy_class, create_dummy_func
from .wrappers import _NewEmptyTensorOp
class _DeformConv(Function):
@staticmethod
def forward(
ctx,
input,
offset,
weight,
stride=1,
padding=0,
dilation=1,
groups=1,
deformable_groups=1,
im2col_step=64,
):
if input is not None and input.dim() != 4:
raise ValueError(
"Expected 4D tensor as input, got {}D tensor instead.".format(input.dim())
)
ctx.stride = _pair(stride)
ctx.padding = _pair(padding)
ctx.dilation = _pair(dilation)
ctx.groups = groups
ctx.deformable_groups = deformable_groups
ctx.im2col_step = im2col_step
ctx.save_for_backward(input, offset, weight)
output = input.new_empty(
_DeformConv._output_size(input, weight, ctx.padding, ctx.dilation, ctx.stride)
)
ctx.bufs_ = [input.new_empty(0), input.new_empty(0)] # columns, ones
if not input.is_cuda:
# TODO: let torchvision support full features of our deformconv.
if deformable_groups != 1:
raise NotImplementedError(
"Deformable Conv with deformable_groups != 1 is not supported on CPUs!"
)
return deform_conv2d(
input, offset, weight, stride=stride, padding=padding, dilation=dilation
)
else:
cur_im2col_step = _DeformConv._cal_im2col_step(input.shape[0], ctx.im2col_step)
assert (input.shape[0] % cur_im2col_step) == 0, "im2col step must divide batchsize"
_C.deform_conv_forward(
input,
weight,
offset,
output,
ctx.bufs_[0],
ctx.bufs_[1],
weight.size(3),
weight.size(2),
ctx.stride[1],
ctx.stride[0],
ctx.padding[1],
ctx.padding[0],
ctx.dilation[1],
ctx.dilation[0],
ctx.groups,
ctx.deformable_groups,
cur_im2col_step,
)
return output
@staticmethod
@once_differentiable
def backward(ctx, grad_output):
input, offset, weight = ctx.saved_tensors
grad_input = grad_offset = grad_weight = None
if not grad_output.is_cuda:
raise NotImplementedError("Deformable Conv is not supported on CPUs!")
else:
cur_im2col_step = _DeformConv._cal_im2col_step(input.shape[0], ctx.im2col_step)
assert (input.shape[0] % cur_im2col_step) == 0, "im2col step must divide batchsize"
if ctx.needs_input_grad[0] or ctx.needs_input_grad[1]:
grad_input = torch.zeros_like(input)
grad_offset = torch.zeros_like(offset)
_C.deform_conv_backward_input(
input,
offset,
grad_output,
grad_input,
grad_offset,
weight,
ctx.bufs_[0],
weight.size(3),
weight.size(2),
ctx.stride[1],
ctx.stride[0],
ctx.padding[1],
ctx.padding[0],
ctx.dilation[1],
ctx.dilation[0],
ctx.groups,
ctx.deformable_groups,
cur_im2col_step,
)
if ctx.needs_input_grad[2]:
grad_weight = torch.zeros_like(weight)
_C.deform_conv_backward_filter(
input,
offset,
grad_output,
grad_weight,
ctx.bufs_[0],
ctx.bufs_[1],
weight.size(3),
weight.size(2),
ctx.stride[1],
ctx.stride[0],
ctx.padding[1],
ctx.padding[0],
ctx.dilation[1],
ctx.dilation[0],
ctx.groups,
ctx.deformable_groups,
1,
cur_im2col_step,
)
return grad_input, grad_offset, grad_weight, None, None, None, None, None, None
@staticmethod
def _output_size(input, weight, padding, dilation, stride):
channels = weight.size(0)
output_size = (input.size(0), channels)
for d in range(input.dim() - 2):
in_size = input.size(d + 2)
pad = padding[d]
kernel = dilation[d] * (weight.size(d + 2) - 1) + 1
stride_ = stride[d]
output_size += ((in_size + (2 * pad) - kernel) // stride_ + 1,)
if not all(map(lambda s: s > 0, output_size)):
raise ValueError(
"convolution input is too small (output would be {})".format(
"x".join(map(str, output_size))
)
)
return output_size
@staticmethod
@lru_cache(maxsize=128)
def _cal_im2col_step(input_size, default_size):
"""
Calculate proper im2col step size, which should be divisible by input_size and not larger
than prefer_size. Meanwhile the step size should be as large as possible to be more
efficient. So we choose the largest one among all divisors of input_size which are smaller
than prefer_size.
:param input_size: input batch size .
:param default_size: default preferred im2col step size.
:return: the largest proper step size.
"""
if input_size <= default_size:
return input_size
best_step = 1
for step in range(2, min(int(math.sqrt(input_size)) + 1, default_size)):
if input_size % step == 0:
if input_size // step <= default_size:
return input_size // step
best_step = step
return best_step
class _ModulatedDeformConv(Function):
@staticmethod
def forward(
ctx,
input,
offset,
mask,
weight,
bias=None,
stride=1,
padding=0,
dilation=1,
groups=1,
deformable_groups=1,
):
ctx.stride = stride
ctx.padding = padding
ctx.dilation = dilation
ctx.groups = groups
ctx.deformable_groups = deformable_groups
ctx.with_bias = bias is not None
if not ctx.with_bias:
bias = input.new_empty(1) # fake tensor
if not input.is_cuda:
raise NotImplementedError("Deformable Conv is not supported on CPUs!")
if (
weight.requires_grad
or mask.requires_grad
or offset.requires_grad
or input.requires_grad
):
ctx.save_for_backward(input, offset, mask, weight, bias)
output = input.new_empty(_ModulatedDeformConv._infer_shape(ctx, input, weight))
ctx._bufs = [input.new_empty(0), input.new_empty(0)]
_C.modulated_deform_conv_forward(
input,
weight,
bias,
ctx._bufs[0],
offset,
mask,
output,
ctx._bufs[1],
weight.shape[2],
weight.shape[3],
ctx.stride,
ctx.stride,
ctx.padding,
ctx.padding,
ctx.dilation,
ctx.dilation,
ctx.groups,
ctx.deformable_groups,
ctx.with_bias,
)
return output
@staticmethod
@once_differentiable
def backward(ctx, grad_output):
if not grad_output.is_cuda:
raise NotImplementedError("Deformable Conv is not supported on CPUs!")
input, offset, mask, weight, bias = ctx.saved_tensors
grad_input = torch.zeros_like(input)
grad_offset = torch.zeros_like(offset)
grad_mask = torch.zeros_like(mask)
grad_weight = torch.zeros_like(weight)
grad_bias = torch.zeros_like(bias)
_C.modulated_deform_conv_backward(
input,
weight,
bias,
ctx._bufs[0],
offset,
mask,
ctx._bufs[1],
grad_input,
grad_weight,
grad_bias,
grad_offset,
grad_mask,
grad_output,
weight.shape[2],
weight.shape[3],
ctx.stride,
ctx.stride,
ctx.padding,
ctx.padding,
ctx.dilation,
ctx.dilation,
ctx.groups,
ctx.deformable_groups,
ctx.with_bias,
)
if not ctx.with_bias:
grad_bias = None
return (
grad_input,
grad_offset,
grad_mask,
grad_weight,
grad_bias,
None,
None,
None,
None,
None,
)
@staticmethod
def _infer_shape(ctx, input, weight):
n = input.size(0)
channels_out = weight.size(0)
height, width = input.shape[2:4]
kernel_h, kernel_w = weight.shape[2:4]
height_out = (
height + 2 * ctx.padding - (ctx.dilation * (kernel_h - 1) + 1)
) // ctx.stride + 1
width_out = (
width + 2 * ctx.padding - (ctx.dilation * (kernel_w - 1) + 1)
) // ctx.stride + 1
return n, channels_out, height_out, width_out
deform_conv = _DeformConv.apply
modulated_deform_conv = _ModulatedDeformConv.apply
class DeformConv(nn.Module):
def __init__(
self,
in_channels,
out_channels,
kernel_size,
stride=1,
padding=0,
dilation=1,
groups=1,
deformable_groups=1,
bias=False,
norm=None,
activation=None,
):
"""
Deformable convolution from :paper:`deformconv`.
Arguments are similar to :class:`Conv2D`. Extra arguments:
Args:
deformable_groups (int): number of groups used in deformable convolution.
norm (nn.Module, optional): a normalization layer
activation (callable(Tensor) -> Tensor): a callable activation function
"""
super(DeformConv, self).__init__()
assert not bias
assert in_channels % groups == 0, "in_channels {} cannot be divisible by groups {}".format(
in_channels, groups
)
assert (
out_channels % groups == 0
), "out_channels {} cannot be divisible by groups {}".format(out_channels, groups)
self.in_channels = in_channels
self.out_channels = out_channels
self.kernel_size = _pair(kernel_size)
self.stride = _pair(stride)
self.padding = _pair(padding)
self.dilation = _pair(dilation)
self.groups = groups
self.deformable_groups = deformable_groups
self.norm = norm
self.activation = activation
self.weight = nn.Parameter(
torch.Tensor(out_channels, in_channels // self.groups, *self.kernel_size)
)
self.bias = None
nn.init.kaiming_uniform_(self.weight, nonlinearity="relu")
def forward(self, x, offset):
if x.numel() == 0:
# When input is empty, we want to return a empty tensor with "correct" shape,
# So that the following operations will not panic
# if they check for the shape of the tensor.
# This computes the height and width of the output tensor
output_shape = [
(i + 2 * p - (di * (k - 1) + 1)) // s + 1
for i, p, di, k, s in zip(
x.shape[-2:], self.padding, self.dilation, self.kernel_size, self.stride
)
]
output_shape = [x.shape[0], self.weight.shape[0]] + output_shape
return _NewEmptyTensorOp.apply(x, output_shape)
x = deform_conv(
x,
offset,
self.weight,
self.stride,
self.padding,
self.dilation,
self.groups,
self.deformable_groups,
)
if self.norm is not None:
x = self.norm(x)
if self.activation is not None:
x = self.activation(x)
return x
def extra_repr(self):
tmpstr = "in_channels=" + str(self.in_channels)
tmpstr += ", out_channels=" + str(self.out_channels)
tmpstr += ", kernel_size=" + str(self.kernel_size)
tmpstr += ", stride=" + str(self.stride)
tmpstr += ", padding=" + str(self.padding)
tmpstr += ", dilation=" + str(self.dilation)
tmpstr += ", groups=" + str(self.groups)
tmpstr += ", deformable_groups=" + str(self.deformable_groups)
tmpstr += ", bias=False"
return tmpstr
class ModulatedDeformConv(nn.Module):
def __init__(
self,
in_channels,
out_channels,
kernel_size,
stride=1,
padding=0,
dilation=1,
groups=1,
deformable_groups=1,
bias=True,
norm=None,
activation=None,
):
"""
Modulated deformable convolution from :paper:`deformconv2`.
Arguments are similar to :class:`Conv2D`. Extra arguments:
Args:
deformable_groups (int): number of groups used in deformable convolution.
norm (nn.Module, optional): a normalization layer
activation (callable(Tensor) -> Tensor): a callable activation function
"""
super(ModulatedDeformConv, self).__init__()
self.in_channels = in_channels
self.out_channels = out_channels
self.kernel_size = _pair(kernel_size)
self.stride = stride
self.padding = padding
self.dilation = dilation
self.groups = groups
self.deformable_groups = deformable_groups
self.with_bias = bias
self.norm = norm
self.activation = activation
self.weight = nn.Parameter(
torch.Tensor(out_channels, in_channels // groups, *self.kernel_size)
)
if bias:
self.bias = nn.Parameter(torch.Tensor(out_channels))
else:
self.bias = None
nn.init.kaiming_uniform_(self.weight, nonlinearity="relu")
if self.bias is not None:
nn.init.constant_(self.bias, 0)
def forward(self, x, offset, mask):
if x.numel() == 0:
output_shape = [
(i + 2 * p - (di * (k - 1) + 1)) // s + 1
for i, p, di, k, s in zip(
x.shape[-2:], self.padding, self.dilation, self.kernel_size, self.stride
)
]
output_shape = [x.shape[0], self.weight.shape[0]] + output_shape
return _NewEmptyTensorOp.apply(x, output_shape)
x = modulated_deform_conv(
x,
offset,
mask,
self.weight,
self.bias,
self.stride,
self.padding,
self.dilation,
self.groups,
self.deformable_groups,
)
if self.norm is not None:
x = self.norm(x)
if self.activation is not None:
x = self.activation(x)
return x
def extra_repr(self):
tmpstr = "in_channels=" + str(self.in_channels)
tmpstr += ", out_channels=" + str(self.out_channels)
tmpstr += ", kernel_size=" + str(self.kernel_size)
tmpstr += ", stride=" + str(self.stride)
tmpstr += ", padding=" + str(self.padding)
tmpstr += ", dilation=" + str(self.dilation)
tmpstr += ", groups=" + str(self.groups)
tmpstr += ", deformable_groups=" + str(self.deformable_groups)
tmpstr += ", bias=" + str(self.with_bias)
return tmpstr
try:
from detectron2 import _C
except ImportError:
# TODO: register ops natively so there is no need to import _C.
_msg = "detectron2 is not compiled successfully, please build following the instructions!"
_args = ("detectron2._C", _msg)
DeformConv = create_dummy_class("DeformConv", *_args)
ModulatedDeformConv = create_dummy_class("ModulatedDeformConv", *_args)
deform_conv = create_dummy_func("deform_conv", *_args)
modulated_deform_conv = create_dummy_func("modulated_deform_conv", *_args)
|