Spaces:
Runtime error
Runtime error
# Copyright (c) SenseTime Research. All rights reserved. | |
# Copyright (c) 2021, NVIDIA CORPORATION. All rights reserved. | |
# | |
# NVIDIA CORPORATION and its licensors retain all intellectual property | |
# and proprietary rights in and to this software, related documentation | |
# and any modifications thereto. Any use, reproduction, disclosure or | |
# distribution of this software and related documentation without an express | |
# license agreement from NVIDIA CORPORATION is strictly prohibited. | |
"""Custom PyTorch ops for efficient resampling of 2D images.""" | |
import os | |
import warnings | |
import numpy as np | |
import torch | |
import traceback | |
from .. import custom_ops | |
from .. import misc | |
from . import conv2d_gradfix | |
#---------------------------------------------------------------------------- | |
_inited = False | |
_plugin = None | |
def _init(): | |
global _inited, _plugin | |
if not _inited: | |
sources = ['upfirdn2d.cpp', 'upfirdn2d.cu'] | |
sources = [os.path.join(os.path.dirname(__file__), s) for s in sources] | |
try: | |
_plugin = custom_ops.get_plugin('upfirdn2d_plugin', sources=sources, extra_cuda_cflags=['--use_fast_math']) | |
except: | |
warnings.warn('Failed to build CUDA kernels for upfirdn2d. Falling back to slow reference implementation. Details:\n\n' + traceback.format_exc()) | |
return _plugin is not None | |
def _parse_scaling(scaling): | |
if isinstance(scaling, int): | |
scaling = [scaling, scaling] | |
assert isinstance(scaling, (list, tuple)) | |
assert all(isinstance(x, int) for x in scaling) | |
sx, sy = scaling | |
assert sx >= 1 and sy >= 1 | |
return sx, sy | |
def _parse_padding(padding): | |
if isinstance(padding, int): | |
padding = [padding, padding] | |
assert isinstance(padding, (list, tuple)) | |
assert all(isinstance(x, int) for x in padding) | |
if len(padding) == 2: | |
padx, pady = padding | |
padding = [padx, padx, pady, pady] | |
padx0, padx1, pady0, pady1 = padding | |
return padx0, padx1, pady0, pady1 | |
def _get_filter_size(f): | |
if f is None: | |
return 1, 1 | |
assert isinstance(f, torch.Tensor) and f.ndim in [1, 2] | |
fw = f.shape[-1] | |
fh = f.shape[0] | |
with misc.suppress_tracer_warnings(): | |
fw = int(fw) | |
fh = int(fh) | |
misc.assert_shape(f, [fh, fw][:f.ndim]) | |
assert fw >= 1 and fh >= 1 | |
return fw, fh | |
#---------------------------------------------------------------------------- | |
def setup_filter(f, device=torch.device('cpu'), normalize=True, flip_filter=False, gain=1, separable=None): | |
r"""Convenience function to setup 2D FIR filter for `upfirdn2d()`. | |
Args: | |
f: Torch tensor, numpy array, or python list of the shape | |
`[filter_height, filter_width]` (non-separable), | |
`[filter_taps]` (separable), | |
`[]` (impulse), or | |
`None` (identity). | |
device: Result device (default: cpu). | |
normalize: Normalize the filter so that it retains the magnitude | |
for constant input signal (DC)? (default: True). | |
flip_filter: Flip the filter? (default: False). | |
gain: Overall scaling factor for signal magnitude (default: 1). | |
separable: Return a separable filter? (default: select automatically). | |
Returns: | |
Float32 tensor of the shape | |
`[filter_height, filter_width]` (non-separable) or | |
`[filter_taps]` (separable). | |
""" | |
# Validate. | |
if f is None: | |
f = 1 | |
f = torch.as_tensor(f, dtype=torch.float32) | |
assert f.ndim in [0, 1, 2] | |
assert f.numel() > 0 | |
if f.ndim == 0: | |
f = f[np.newaxis] | |
# Separable? | |
if separable is None: | |
separable = (f.ndim == 1 and f.numel() >= 8) | |
if f.ndim == 1 and not separable: | |
f = f.ger(f) | |
assert f.ndim == (1 if separable else 2) | |
# Apply normalize, flip, gain, and device. | |
if normalize: | |
f /= f.sum() | |
if flip_filter: | |
f = f.flip(list(range(f.ndim))) | |
f = f * (gain ** (f.ndim / 2)) | |
f = f.to(device=device) | |
return f | |
#---------------------------------------------------------------------------- | |
def upfirdn2d(x, f, up=1, down=1, padding=0, flip_filter=False, gain=1, impl='cuda'): | |
r"""Pad, upsample, filter, and downsample a batch of 2D images. | |
Performs the following sequence of operations for each channel: | |
1. Upsample the image by inserting N-1 zeros after each pixel (`up`). | |
2. Pad the image with the specified number of zeros on each side (`padding`). | |
Negative padding corresponds to cropping the image. | |
3. Convolve the image with the specified 2D FIR filter (`f`), shrinking it | |
so that the footprint of all output pixels lies within the input image. | |
4. Downsample the image by keeping every Nth pixel (`down`). | |
This sequence of operations bears close resemblance to scipy.signal.upfirdn(). | |
The fused op is considerably more efficient than performing the same calculation | |
using standard PyTorch ops. It supports gradients of arbitrary order. | |
Args: | |
x: Float32/float64/float16 input tensor of the shape | |
`[batch_size, num_channels, in_height, in_width]`. | |
f: Float32 FIR filter of the shape | |
`[filter_height, filter_width]` (non-separable), | |
`[filter_taps]` (separable), or | |
`None` (identity). | |
up: Integer upsampling factor. Can be a single int or a list/tuple | |
`[x, y]` (default: 1). | |
down: Integer downsampling factor. Can be a single int or a list/tuple | |
`[x, y]` (default: 1). | |
padding: Padding with respect to the upsampled image. Can be a single number | |
or a list/tuple `[x, y]` or `[x_before, x_after, y_before, y_after]` | |
(default: 0). | |
flip_filter: False = convolution, True = correlation (default: False). | |
gain: Overall scaling factor for signal magnitude (default: 1). | |
impl: Implementation to use. Can be `'ref'` or `'cuda'` (default: `'cuda'`). | |
Returns: | |
Tensor of the shape `[batch_size, num_channels, out_height, out_width]`. | |
""" | |
assert isinstance(x, torch.Tensor) | |
assert impl in ['ref', 'cuda'] | |
if impl == 'cuda' and x.device.type == 'cuda' and _init(): | |
return _upfirdn2d_cuda(up=up, down=down, padding=padding, flip_filter=flip_filter, gain=gain).apply(x, f) | |
return _upfirdn2d_ref(x, f, up=up, down=down, padding=padding, flip_filter=flip_filter, gain=gain) | |
#---------------------------------------------------------------------------- | |
def _upfirdn2d_ref(x, f, up=1, down=1, padding=0, flip_filter=False, gain=1): | |
"""Slow reference implementation of `upfirdn2d()` using standard PyTorch ops. | |
""" | |
# Validate arguments. | |
assert isinstance(x, torch.Tensor) and x.ndim == 4 | |
if f is None: | |
f = torch.ones([1, 1], dtype=torch.float32, device=x.device) | |
assert isinstance(f, torch.Tensor) and f.ndim in [1, 2] | |
assert f.dtype == torch.float32 and not f.requires_grad | |
batch_size, num_channels, in_height, in_width = x.shape | |
upx, upy = _parse_scaling(up) | |
downx, downy = _parse_scaling(down) | |
padx0, padx1, pady0, pady1 = _parse_padding(padding) | |
# Upsample by inserting zeros. | |
x = x.reshape([batch_size, num_channels, in_height, 1, in_width, 1]) | |
x = torch.nn.functional.pad(x, [0, upx - 1, 0, 0, 0, upy - 1]) | |
x = x.reshape([batch_size, num_channels, in_height * upy, in_width * upx]) | |
# Pad or crop. | |
x = torch.nn.functional.pad(x, [max(padx0, 0), max(padx1, 0), max(pady0, 0), max(pady1, 0)]) | |
x = x[:, :, max(-pady0, 0) : x.shape[2] - max(-pady1, 0), max(-padx0, 0) : x.shape[3] - max(-padx1, 0)] | |
# Setup filter. | |
f = f * (gain ** (f.ndim / 2)) | |
f = f.to(x.dtype) | |
if not flip_filter: | |
f = f.flip(list(range(f.ndim))) | |
# Convolve with the filter. | |
f = f[np.newaxis, np.newaxis].repeat([num_channels, 1] + [1] * f.ndim) | |
if f.ndim == 4: | |
x = conv2d_gradfix.conv2d(input=x, weight=f, groups=num_channels) | |
else: | |
x = conv2d_gradfix.conv2d(input=x, weight=f.unsqueeze(2), groups=num_channels) | |
x = conv2d_gradfix.conv2d(input=x, weight=f.unsqueeze(3), groups=num_channels) | |
# Downsample by throwing away pixels. | |
x = x[:, :, ::downy, ::downx] | |
return x | |
#---------------------------------------------------------------------------- | |
_upfirdn2d_cuda_cache = dict() | |
def _upfirdn2d_cuda(up=1, down=1, padding=0, flip_filter=False, gain=1): | |
"""Fast CUDA implementation of `upfirdn2d()` using custom ops. | |
""" | |
# Parse arguments. | |
upx, upy = _parse_scaling(up) | |
downx, downy = _parse_scaling(down) | |
padx0, padx1, pady0, pady1 = _parse_padding(padding) | |
# Lookup from cache. | |
key = (upx, upy, downx, downy, padx0, padx1, pady0, pady1, flip_filter, gain) | |
if key in _upfirdn2d_cuda_cache: | |
return _upfirdn2d_cuda_cache[key] | |
# Forward op. | |
class Upfirdn2dCuda(torch.autograd.Function): | |
def forward(ctx, x, f): # pylint: disable=arguments-differ | |
assert isinstance(x, torch.Tensor) and x.ndim == 4 | |
if f is None: | |
f = torch.ones([1, 1], dtype=torch.float32, device=x.device) | |
assert isinstance(f, torch.Tensor) and f.ndim in [1, 2] | |
y = x | |
if f.ndim == 2: | |
y = _plugin.upfirdn2d(y, f, upx, upy, downx, downy, padx0, padx1, pady0, pady1, flip_filter, gain) | |
else: | |
y = _plugin.upfirdn2d(y, f.unsqueeze(0), upx, 1, downx, 1, padx0, padx1, 0, 0, flip_filter, np.sqrt(gain)) | |
y = _plugin.upfirdn2d(y, f.unsqueeze(1), 1, upy, 1, downy, 0, 0, pady0, pady1, flip_filter, np.sqrt(gain)) | |
ctx.save_for_backward(f) | |
ctx.x_shape = x.shape | |
return y | |
def backward(ctx, dy): # pylint: disable=arguments-differ | |
f, = ctx.saved_tensors | |
_, _, ih, iw = ctx.x_shape | |
_, _, oh, ow = dy.shape | |
fw, fh = _get_filter_size(f) | |
p = [ | |
fw - padx0 - 1, | |
iw * upx - ow * downx + padx0 - upx + 1, | |
fh - pady0 - 1, | |
ih * upy - oh * downy + pady0 - upy + 1, | |
] | |
dx = None | |
df = None | |
if ctx.needs_input_grad[0]: | |
dx = _upfirdn2d_cuda(up=down, down=up, padding=p, flip_filter=(not flip_filter), gain=gain).apply(dy, f) | |
assert not ctx.needs_input_grad[1] | |
return dx, df | |
# Add to cache. | |
_upfirdn2d_cuda_cache[key] = Upfirdn2dCuda | |
return Upfirdn2dCuda | |
#---------------------------------------------------------------------------- | |
def filter2d(x, f, padding=0, flip_filter=False, gain=1, impl='cuda'): | |
r"""Filter a batch of 2D images using the given 2D FIR filter. | |
By default, the result is padded so that its shape matches the input. | |
User-specified padding is applied on top of that, with negative values | |
indicating cropping. Pixels outside the image are assumed to be zero. | |
Args: | |
x: Float32/float64/float16 input tensor of the shape | |
`[batch_size, num_channels, in_height, in_width]`. | |
f: Float32 FIR filter of the shape | |
`[filter_height, filter_width]` (non-separable), | |
`[filter_taps]` (separable), or | |
`None` (identity). | |
padding: Padding with respect to the output. Can be a single number or a | |
list/tuple `[x, y]` or `[x_before, x_after, y_before, y_after]` | |
(default: 0). | |
flip_filter: False = convolution, True = correlation (default: False). | |
gain: Overall scaling factor for signal magnitude (default: 1). | |
impl: Implementation to use. Can be `'ref'` or `'cuda'` (default: `'cuda'`). | |
Returns: | |
Tensor of the shape `[batch_size, num_channels, out_height, out_width]`. | |
""" | |
padx0, padx1, pady0, pady1 = _parse_padding(padding) | |
fw, fh = _get_filter_size(f) | |
p = [ | |
padx0 + fw // 2, | |
padx1 + (fw - 1) // 2, | |
pady0 + fh // 2, | |
pady1 + (fh - 1) // 2, | |
] | |
return upfirdn2d(x, f, padding=p, flip_filter=flip_filter, gain=gain, impl=impl) | |
#---------------------------------------------------------------------------- | |
def upsample2d(x, f, up=2, padding=0, flip_filter=False, gain=1, impl='cuda'): | |
r"""Upsample a batch of 2D images using the given 2D FIR filter. | |
By default, the result is padded so that its shape is a multiple of the input. | |
User-specified padding is applied on top of that, with negative values | |
indicating cropping. Pixels outside the image are assumed to be zero. | |
Args: | |
x: Float32/float64/float16 input tensor of the shape | |
`[batch_size, num_channels, in_height, in_width]`. | |
f: Float32 FIR filter of the shape | |
`[filter_height, filter_width]` (non-separable), | |
`[filter_taps]` (separable), or | |
`None` (identity). | |
up: Integer upsampling factor. Can be a single int or a list/tuple | |
`[x, y]` (default: 1). | |
padding: Padding with respect to the output. Can be a single number or a | |
list/tuple `[x, y]` or `[x_before, x_after, y_before, y_after]` | |
(default: 0). | |
flip_filter: False = convolution, True = correlation (default: False). | |
gain: Overall scaling factor for signal magnitude (default: 1). | |
impl: Implementation to use. Can be `'ref'` or `'cuda'` (default: `'cuda'`). | |
Returns: | |
Tensor of the shape `[batch_size, num_channels, out_height, out_width]`. | |
""" | |
upx, upy = _parse_scaling(up) | |
padx0, padx1, pady0, pady1 = _parse_padding(padding) | |
fw, fh = _get_filter_size(f) | |
p = [ | |
padx0 + (fw + upx - 1) // 2, | |
padx1 + (fw - upx) // 2, | |
pady0 + (fh + upy - 1) // 2, | |
pady1 + (fh - upy) // 2, | |
] | |
return upfirdn2d(x, f, up=up, padding=p, flip_filter=flip_filter, gain=gain*upx*upy, impl=impl) | |
#---------------------------------------------------------------------------- | |
def downsample2d(x, f, down=2, padding=0, flip_filter=False, gain=1, impl='cuda'): | |
r"""Downsample a batch of 2D images using the given 2D FIR filter. | |
By default, the result is padded so that its shape is a fraction of the input. | |
User-specified padding is applied on top of that, with negative values | |
indicating cropping. Pixels outside the image are assumed to be zero. | |
Args: | |
x: Float32/float64/float16 input tensor of the shape | |
`[batch_size, num_channels, in_height, in_width]`. | |
f: Float32 FIR filter of the shape | |
`[filter_height, filter_width]` (non-separable), | |
`[filter_taps]` (separable), or | |
`None` (identity). | |
down: Integer downsampling factor. Can be a single int or a list/tuple | |
`[x, y]` (default: 1). | |
padding: Padding with respect to the input. Can be a single number or a | |
list/tuple `[x, y]` or `[x_before, x_after, y_before, y_after]` | |
(default: 0). | |
flip_filter: False = convolution, True = correlation (default: False). | |
gain: Overall scaling factor for signal magnitude (default: 1). | |
impl: Implementation to use. Can be `'ref'` or `'cuda'` (default: `'cuda'`). | |
Returns: | |
Tensor of the shape `[batch_size, num_channels, out_height, out_width]`. | |
""" | |
downx, downy = _parse_scaling(down) | |
padx0, padx1, pady0, pady1 = _parse_padding(padding) | |
fw, fh = _get_filter_size(f) | |
p = [ | |
padx0 + (fw - downx + 1) // 2, | |
padx1 + (fw - downx) // 2, | |
pady0 + (fh - downy + 1) // 2, | |
pady1 + (fh - downy) // 2, | |
] | |
return upfirdn2d(x, f, down=down, padding=p, flip_filter=flip_filter, gain=gain, impl=impl) | |
#---------------------------------------------------------------------------- | |