File size: 5,775 Bytes
8f87579
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
'''
Original from https://github.com/CSAILVision/GANDissect
Modified by Erik Härkönen, 29.11.2019
'''

import numbers
import torch
from netdissect.autoeval import autoimport_eval
from netdissect.progress import print_progress
from netdissect.nethook import InstrumentedModel
from netdissect.easydict import EasyDict

def create_instrumented_model(args, **kwargs):
    '''
    Creates an instrumented model out of a namespace of arguments that
    correspond to ArgumentParser command-line args:
      model: a string to evaluate as a constructor for the model.
      pthfile: (optional) filename of .pth file for the model.
      layers: a list of layers to instrument, defaulted if not provided.
      edit: True to instrument the layers for editing.
      gen: True for a generator model.  One-pixel input assumed.
      imgsize: For non-generator models, (y, x) dimensions for RGB input.
      cuda: True to use CUDA.
  
    The constructed model will be decorated with the following attributes:
      input_shape: (usually 4d) tensor shape for single-image input.
      output_shape: 4d tensor shape for output.
      feature_shape: map of layer names to 4d tensor shape for featuremaps.
      retained: map of layernames to tensors, filled after every evaluation.
      ablation: if editing, map of layernames to [0..1] alpha values to fill.
      replacement: if editing, map of layernames to values to fill.

    When editing, the feature value x will be replaced by:
        `x = (replacement * ablation) + (x * (1 - ablation))`
    '''

    args = EasyDict(vars(args), **kwargs)

    # Construct the network
    if args.model is None:
        print_progress('No model specified')
        return None
    if isinstance(args.model, torch.nn.Module):
        model = args.model
    else:
        model = autoimport_eval(args.model)
    # Unwrap any DataParallel-wrapped model
    if isinstance(model, torch.nn.DataParallel):
        model = next(model.children())

    # Load its state dict
    meta = {}
    if getattr(args, 'pthfile', None) is not None:
        data = torch.load(args.pthfile)
        if 'state_dict' in data:
            meta = {}
            for key in data:
                if isinstance(data[key], numbers.Number):
                    meta[key] = data[key]
            data = data['state_dict']
        submodule = getattr(args, 'submodule', None)
        if submodule is not None and len(submodule):
            remove_prefix = submodule + '.'
            data = { k[len(remove_prefix):]: v for k, v in data.items()
                    if k.startswith(remove_prefix)}
            if not len(data):
                print_progress('No submodule %s found in %s' %
                        (submodule, args.pthfile))
                return None
        model.load_state_dict(data, strict=not getattr(args, 'unstrict', False))

    # Decide which layers to instrument.
    if getattr(args, 'layer', None) is not None:
        args.layers = [args.layer]
    if getattr(args, 'layers', None) is None:
        # Skip wrappers with only one named model
        container = model
        prefix = ''
        while len(list(container.named_children())) == 1:
            name, container = next(container.named_children())
            prefix += name + '.'
        # Default to all nontrivial top-level layers except last.
        args.layers = [prefix + name
                for name, module in container.named_children()
                if type(module).__module__ not in [
                    # Skip ReLU and other activations.
                    'torch.nn.modules.activation',
                    # Skip pooling layers.
                    'torch.nn.modules.pooling']
                ][:-1]
        print_progress('Defaulting to layers: %s' % ' '.join(args.layers))

    # Now wrap the model for instrumentation.
    model = InstrumentedModel(model)
    model.meta = meta

    # Instrument the layers.
    model.retain_layers(args.layers)
    model.eval()
    if args.cuda:
        model.cuda()

    # Annotate input, output, and feature shapes
    annotate_model_shapes(model,
            gen=getattr(args, 'gen', False),
            imgsize=getattr(args, 'imgsize', None),
            latent_shape=getattr(args, 'latent_shape', None))
    return model

def annotate_model_shapes(model, gen=False, imgsize=None, latent_shape=None):
    assert (imgsize is not None) or gen

    # Figure the input shape.
    if gen:
        if latent_shape is None:
            # We can guess a generator's input shape by looking at the model.
            # Examine first conv in model to determine input feature size.
            first_layer = [c for c in model.modules()
                    if isinstance(c, (torch.nn.Conv2d, torch.nn.ConvTranspose2d,
                        torch.nn.Linear))][0]
            # 4d input if convolutional, 2d input if first layer is linear.
            if isinstance(first_layer, (torch.nn.Conv2d, torch.nn.ConvTranspose2d)):
                input_shape = (1, first_layer.in_channels, 1, 1)
            else:
                input_shape = (1, first_layer.in_features)
        else:
            # Specify input shape manually
            input_shape = latent_shape
    else:
        # For a classifier, the input image shape is given as an argument.
        input_shape = (1, 3) + tuple(imgsize)

    # Run the model once to observe feature shapes.
    device = next(model.parameters()).device
    dry_run = torch.zeros(input_shape).to(device)
    with torch.no_grad():
        output = model(dry_run)

    # Annotate shapes.
    model.input_shape = input_shape
    model.feature_shape = { layer: feature.shape
            for layer, feature in model.retained_features().items() }
    model.output_shape = output.shape
    return model