File size: 10,697 Bytes
f670afc
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
# Copyright (C) 2021 NVIDIA CORPORATION & AFFILIATES.  All rights reserved.
#
# This work is made available under the Nvidia Source Code License-NC.
# To view a copy of this license, check out LICENSE.md
# Copyright (C) 2020 NVIDIA Corporation.  All rights reserved
import functools
import warnings

import numpy as np
import torch
import torch.nn as nn

from imaginaire.layers import Conv2dBlock
from imaginaire.utils.data import (get_paired_input_image_channel_number,
                                   get_paired_input_label_channel_number)
from imaginaire.utils.distributed import master_only_print as print
from model.sample import Equirectangular

class Discriminator(nn.Module):
    r"""Multi-resolution patch discriminator.

    Args:
        dis_cfg (obj): Discriminator definition part of the yaml config
            file.
        data_cfg (obj): Data definition part of the yaml config file.
    """

    def __init__(self, dis_cfg):
        super(Discriminator, self).__init__()
        print('Multi-resolution patch discriminator initialization.')
        # We assume the first datum is the ground truth image.
        num_input_channels = getattr(dis_cfg, 'input_channels', 3)
        # Calculate number of channels in the input label.

        # Build the discriminator.
        kernel_size = getattr(dis_cfg, 'kernel_size', 3)
        num_filters = getattr(dis_cfg, 'num_filters', 128)
        max_num_filters = getattr(dis_cfg, 'max_num_filters', 512)
        num_discriminators = getattr(dis_cfg, 'num_discriminators', 2)
        num_layers = getattr(dis_cfg, 'num_layers', 5)
        activation_norm_type = getattr(dis_cfg, 'activation_norm_type', 'none')
        weight_norm_type = getattr(dis_cfg, 'weight_norm_type', 'spectral')
        print('\tBase filter number: %d' % num_filters)
        print('\tNumber of discriminators: %d' % num_discriminators)
        print('\tNumber of layers in a discriminator: %d' % num_layers)
        print('\tWeight norm type: %s' % weight_norm_type)
        self.condition = getattr(dis_cfg, 'condition', None)
        # self.condition = dis_cfg.condition
        self.model = MultiResPatchDiscriminator(num_discriminators,
                                                kernel_size,
                                                num_input_channels,
                                                num_filters,
                                                num_layers,
                                                max_num_filters,
                                                activation_norm_type,
                                                weight_norm_type)
        print('Done with the Multi-resolution patch '
              'discriminator initialization.')

    def forward(self, data, net_G_output, real=True):
        r"""SPADE Generator forward.

        Args:
            data  (N x C1 x H x W tensor) : Ground truth images.
            net_G_output (dict):
                fake_images  (N x C1 x H x W tensor) : Fake images.
            real (bool): If ``True``, also classifies real images. Otherwise it
                only classifies generated images to save computation during the
                generator update.
        Returns:
            (tuple):
              - real_outputs (list): list of output tensors produced by
              - individual patch discriminators for real images.
              - real_features (list): list of lists of features produced by
                individual patch discriminators for real images.
              - fake_outputs (list): list of output tensors produced by
                individual patch discriminators for fake images.
              - fake_features (list): list of lists of features produced by
                individual patch discriminators for fake images.
        """
        output_x = dict()
        if self.condition:
            fake_input_x = torch.cat([net_G_output['pred'],net_G_output['generator_inputs']],dim=1)
        else:
            fake_input_x = net_G_output['pred']
        output_x['fake_outputs'], output_x['fake_features'], _ = \
            self.model.forward(fake_input_x)
        if real:
            if self.condition:
                real_input_x = torch.cat([net_G_output['pred'],net_G_output['generator_inputs']],dim=1)
            else:
                real_input_x = data
            output_x['real_outputs'], output_x['real_features'], _ = \
                self.model.forward(real_input_x)
        return output_x


class MultiResPatchDiscriminator(nn.Module):
    r"""Multi-resolution patch discriminator.

    Args:
        num_discriminators (int): Num. of discriminators (one per scale).
        kernel_size (int): Convolution kernel size.
        num_image_channels (int): Num. of channels in the real/fake image.
        num_filters (int): Num. of base filters in a layer.
        num_layers (int): Num. of layers for the patch discriminator.
        max_num_filters (int): Maximum num. of filters in a layer.
        activation_norm_type (str): batch_norm/instance_norm/none/....
        weight_norm_type (str): none/spectral_norm/weight_norm
    """

    def __init__(self,
                 num_discriminators=3,
                 kernel_size=3,
                 num_image_channels=3,
                 num_filters=64,
                 num_layers=4,
                 max_num_filters=512,
                 activation_norm_type='',
                 weight_norm_type='',
                 **kwargs):
        super().__init__()
        for key in kwargs:
            if key != 'type' and key != 'patch_wise':
                warnings.warn(
                    "Discriminator argument {} is not used".format(key))

        self.discriminators = nn.ModuleList()
        for i in range(num_discriminators):
            net_discriminator = NLayerPatchDiscriminator(
                kernel_size,
                num_image_channels,
                num_filters,
                num_layers,
                max_num_filters,
                activation_norm_type,
                weight_norm_type)
            self.discriminators.append(net_discriminator)
        print('Done with the Multi-resolution patch '
              'discriminator initialization.')
        self.e = Equirectangular(theta=[-40., 40.],width = 128, height = 128,FovX = 100)

    def forward(self, input_x):
        r"""Multi-resolution patch discriminator forward.

        Args:
            input_x (tensor) : Input images.
        Returns:
            (tuple):
              - output_list (list): list of output tensors produced by
                individual patch discriminators.
              - features_list (list): list of lists of features produced by
                individual patch discriminators.
              - input_list (list): list of downsampled input images.
        """
        input_list = []
        output_list = []
        features_list = []
        input_N = nn.functional.interpolate(
            input_x, scale_factor=0.5, mode='bilinear',
            align_corners=True, recompute_scale_factor=True)
        equ= self.e(input_x)
        for i, net_discriminator in enumerate(self.discriminators):
            input_list.append(input_N)
            output, features = net_discriminator(input_N)
            output_list.append(output)
            features_list.append(features)
            if i == 0:
                input_N = torch.nn.functional.grid_sample(input_x, equ.float(), align_corners = True)*0.99
            elif i == 1:
                input_N = nn.functional.interpolate(
                    input_N, scale_factor=0.5, mode='bilinear',
                    align_corners=True, recompute_scale_factor=True)

        return output_list, features_list, input_list

class NLayerPatchDiscriminator(nn.Module):
    r"""Patch Discriminator constructor.

    Args:
        kernel_size (int): Convolution kernel size.
        num_input_channels (int): Num. of channels in the real/fake image.
        num_filters (int): Num. of base filters in a layer.
        num_layers (int): Num. of layers for the patch discriminator.
        max_num_filters (int): Maximum num. of filters in a layer.
        activation_norm_type (str): batch_norm/instance_norm/none/....
        weight_norm_type (str): none/spectral_norm/weight_norm
    """

    def __init__(self,
                 kernel_size,
                 num_input_channels,
                 num_filters,
                 num_layers,
                 max_num_filters,
                 activation_norm_type,
                 weight_norm_type):
        super(NLayerPatchDiscriminator, self).__init__()
        self.num_layers = num_layers
        padding = int(np.floor((kernel_size - 1.0) / 2))
        nonlinearity = 'leakyrelu'
        base_conv2d_block = \
            functools.partial(Conv2dBlock,
                              kernel_size=kernel_size,
                              padding=padding,
                              weight_norm_type=weight_norm_type,
                              activation_norm_type=activation_norm_type,
                              nonlinearity=nonlinearity,
                              # inplace_nonlinearity=True,
                              order='CNA')
        layers = [[base_conv2d_block(
            num_input_channels, num_filters, stride=2)]]
        for n in range(num_layers):
            num_filters_prev = num_filters
            num_filters = min(num_filters * 2, max_num_filters)
            stride = 2 if n < (num_layers - 1) else 1
            layers += [[base_conv2d_block(num_filters_prev, num_filters,
                                          stride=stride)]]
        layers += [[Conv2dBlock(num_filters, 1,
                                3, 1,
                                padding,
                                weight_norm_type=weight_norm_type)]]
        for n in range(len(layers)):
            setattr(self, 'layer' + str(n), nn.Sequential(*layers[n]))
        

    def forward(self, input_x):
        r"""Patch Discriminator forward.

        Args:
            input_x (N x C x H1 x W2 tensor): Concatenation of images and
                semantic representations.
        Returns:
            (tuple):
              - output (N x 1 x H2 x W2 tensor): Discriminator output value.
                Before the sigmoid when using NSGAN.
              - features (list): lists of tensors of the intermediate
                activations.
        """
        res = [input_x]
        for n in range(self.num_layers + 2):
            layer = getattr(self, 'layer' + str(n))
            x = res[-1]
            res.append(layer(x))
        output = res[-1]
        features = res[1:-1]
        return output, features