662 lines
27 KiB
Python
662 lines
27 KiB
Python
"""Custom fastai layers and basic functions to grab them.
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Docs: https://docs.fast.ai/layers.html.md"""
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# AUTOGENERATED! DO NOT EDIT! File to edit: ../nbs/01_layers.ipynb.
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# %% auto #0
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__all__ = ['NormType', 'inplace_relu', 'Mish', 'Swish', 'module', 'Identity', 'Lambda', 'PartialLambda', 'Flatten',
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'ToTensorBase', 'View', 'ResizeBatch', 'Debugger', 'sigmoid_range', 'SigmoidRange', 'AdaptiveConcatPool1d',
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'AdaptiveConcatPool2d', 'PoolType', 'adaptive_pool', 'PoolFlatten', 'BatchNorm', 'InstanceNorm',
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'BatchNorm1dFlat', 'LinBnDrop', 'sigmoid', 'sigmoid_', 'vleaky_relu', 'init_default', 'init_linear',
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'ConvLayer', 'AdaptiveAvgPool', 'MaxPool', 'AvgPool', 'trunc_normal_', 'Embedding', 'SelfAttention',
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'PooledSelfAttention2d', 'SimpleSelfAttention', 'icnr_init', 'PixelShuffle_ICNR', 'sequential',
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'SequentialEx', 'MergeLayer', 'Cat', 'SimpleCNN', 'ProdLayer', 'SEModule', 'ResBlock', 'SEBlock',
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'SEResNeXtBlock', 'SeparableBlock', 'TimeDistributed', 'swish', 'SwishJit', 'MishJitAutoFn', 'mish',
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'MishJit', 'ParameterModule', 'children_and_parameters', 'has_children', 'flatten_model', 'NoneReduce',
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'in_channels']
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# %% ../nbs/01_layers.ipynb #c0d0432b
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from .imports import *
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from .torch_imports import *
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from .torch_core import *
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from torch.nn.utils import weight_norm, spectral_norm
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# %% ../nbs/01_layers.ipynb #ce863de4
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def module(*flds, **defaults):
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"Decorator to create an `nn.Module` using `f` as `forward` method"
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pa = [inspect.Parameter(o, inspect.Parameter.POSITIONAL_OR_KEYWORD) for o in flds]
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pb = [inspect.Parameter(k, inspect.Parameter.POSITIONAL_OR_KEYWORD, default=v)
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for k,v in defaults.items()]
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params = pa+pb
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all_flds = [*flds,*defaults.keys()]
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def _f(f):
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class c(nn.Module):
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def __init__(self, *args, **kwargs):
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super().__init__()
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for i,o in enumerate(args): kwargs[all_flds[i]] = o
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kwargs = merge(defaults,kwargs)
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for k,v in kwargs.items(): setattr(self,k,v)
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__repr__ = basic_repr(all_flds)
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forward = f
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c.__signature__ = inspect.Signature(params)
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c.__name__ = c.__qualname__ = f.__name__
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c.__doc__ = f.__doc__
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return c
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return _f
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# %% ../nbs/01_layers.ipynb #d6b9a636
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@module()
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def Identity(self, x):
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"Do nothing at all"
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return x
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# %% ../nbs/01_layers.ipynb #ee670b7f
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@module('func')
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def Lambda(self, x):
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"An easy way to create a pytorch layer for a simple `func`"
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return self.func(x)
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# %% ../nbs/01_layers.ipynb #a1efb014
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class PartialLambda(Lambda):
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"Layer that applies `partial(func, **kwargs)`"
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def __init__(self, func, **kwargs):
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super().__init__(partial(func, **kwargs))
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self.repr = f'{func.__name__}, {kwargs}'
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def forward(self, x): return self.func(x)
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def __repr__(self): return f'{self.__class__.__name__}({self.repr})'
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# %% ../nbs/01_layers.ipynb #eadd3951
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@module(full=False)
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def Flatten(self, x):
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"Flatten `x` to a single dimension, e.g. at end of a model. `full` for rank-1 tensor"
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return x.view(-1) if self.full else x.view(x.size(0), -1) # Removed cast to Tensorbase
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# %% ../nbs/01_layers.ipynb #67a6ad96
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@module(tensor_cls=TensorBase)
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def ToTensorBase(self, x):
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"Convert x to TensorBase class"
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return self.tensor_cls(x)
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# %% ../nbs/01_layers.ipynb #ca9d98f8
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class View(Module):
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"Reshape `x` to `size`"
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def __init__(self, *size): self.size = size
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def forward(self, x): return x.view(self.size)
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# %% ../nbs/01_layers.ipynb #1c186206
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class ResizeBatch(Module):
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"Reshape `x` to `size`, keeping batch dim the same size"
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def __init__(self, *size): self.size = size
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def forward(self, x): return x.view((x.size(0),) + self.size)
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# %% ../nbs/01_layers.ipynb #33842c11
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@module()
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def Debugger(self,x):
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"A module to debug inside a model."
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set_trace()
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return x
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# %% ../nbs/01_layers.ipynb #7081d561
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def sigmoid_range(x, low, high):
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"Sigmoid function with range `(low, high)`"
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return torch.sigmoid(x) * (high - low) + low
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# %% ../nbs/01_layers.ipynb #1ac1db49
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@module('low','high')
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def SigmoidRange(self, x):
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"Sigmoid module with range `(low, high)`"
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return sigmoid_range(x, self.low, self.high)
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# %% ../nbs/01_layers.ipynb #ec0731ea
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class AdaptiveConcatPool1d(Module):
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"Layer that concats `AdaptiveAvgPool1d` and `AdaptiveMaxPool1d`"
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def __init__(self, size=None):
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self.size = size or 1
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self.ap = nn.AdaptiveAvgPool1d(self.size)
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self.mp = nn.AdaptiveMaxPool1d(self.size)
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def forward(self, x): return torch.cat([self.mp(x), self.ap(x)], 1)
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# %% ../nbs/01_layers.ipynb #703bd845
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class AdaptiveConcatPool2d(Module):
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"Layer that concats `AdaptiveAvgPool2d` and `AdaptiveMaxPool2d`"
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def __init__(self, size=None):
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self.size = size or 1
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self.ap = nn.AdaptiveAvgPool2d(self.size)
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self.mp = nn.AdaptiveMaxPool2d(self.size)
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def forward(self, x): return torch.cat([self.mp(x), self.ap(x)], 1)
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# %% ../nbs/01_layers.ipynb #943a7c16
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class PoolType: Avg,Max,Cat = 'Avg','Max','Cat'
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# %% ../nbs/01_layers.ipynb #91663b01
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def adaptive_pool(pool_type):
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return nn.AdaptiveAvgPool2d if pool_type=='Avg' else nn.AdaptiveMaxPool2d if pool_type=='Max' else AdaptiveConcatPool2d
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# %% ../nbs/01_layers.ipynb #66437aa0
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class PoolFlatten(nn.Sequential):
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"Combine `nn.AdaptiveAvgPool2d` and `Flatten`."
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def __init__(self, pool_type=PoolType.Avg): super().__init__(adaptive_pool(pool_type)(1), Flatten())
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# %% ../nbs/01_layers.ipynb #30140915
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NormType = Enum('NormType', 'Batch BatchZero Weight Spectral Instance InstanceZero')
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# %% ../nbs/01_layers.ipynb #e4aa7f8a
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def _get_norm(prefix, nf, ndim=2, zero=False, **kwargs):
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"Norm layer with `nf` features and `ndim` initialized depending on `norm_type`."
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assert 1 <= ndim <= 3
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bn = getattr(nn, f"{prefix}{ndim}d")(nf, **kwargs)
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if bn.affine:
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bn.bias.data.fill_(1e-3)
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bn.weight.data.fill_(0. if zero else 1.)
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return bn
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# %% ../nbs/01_layers.ipynb #908bd625
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@delegates(nn.BatchNorm2d)
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def BatchNorm(nf, ndim=2, norm_type=NormType.Batch, **kwargs):
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"BatchNorm layer with `nf` features and `ndim` initialized depending on `norm_type`."
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return _get_norm('BatchNorm', nf, ndim, zero=norm_type==NormType.BatchZero, **kwargs)
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# %% ../nbs/01_layers.ipynb #ac0c27df
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@delegates(nn.InstanceNorm2d)
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def InstanceNorm(nf, ndim=2, norm_type=NormType.Instance, affine=True, **kwargs):
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"InstanceNorm layer with `nf` features and `ndim` initialized depending on `norm_type`."
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return _get_norm('InstanceNorm', nf, ndim, zero=norm_type==NormType.InstanceZero, affine=affine, **kwargs)
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# %% ../nbs/01_layers.ipynb #fdc8c476
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class BatchNorm1dFlat(nn.BatchNorm1d):
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"`nn.BatchNorm1d`, but first flattens leading dimensions"
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def forward(self, x):
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if x.dim()==2: return super().forward(x)
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*f,l = x.shape
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x = x.contiguous().view(-1,l)
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return super().forward(x).view(*f,l)
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# %% ../nbs/01_layers.ipynb #03025111
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class LinBnDrop(nn.Sequential):
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"Module grouping `BatchNorm1d`, `Dropout` and `Linear` layers"
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def __init__(self, n_in, n_out, bn=True, p=0., act=None, lin_first=False):
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layers = [BatchNorm(n_out if lin_first else n_in, ndim=1)] if bn else []
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if p != 0: layers.append(nn.Dropout(p))
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lin = [nn.Linear(n_in, n_out, bias=not bn)]
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if act is not None: lin.append(act)
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layers = lin+layers if lin_first else layers+lin
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super().__init__(*layers)
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# %% ../nbs/01_layers.ipynb #6334fe76
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def sigmoid(input, eps=1e-7):
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"Same as `torch.sigmoid`, plus clamping to `(eps,1-eps)"
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return input.sigmoid().clamp(eps,1-eps)
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# %% ../nbs/01_layers.ipynb #600baec7
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def sigmoid_(input, eps=1e-7):
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"Same as `torch.sigmoid_`, plus clamping to `(eps,1-eps)"
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return input.sigmoid_().clamp_(eps,1-eps)
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# %% ../nbs/01_layers.ipynb #4504d29a
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from torch.nn.init import kaiming_uniform_,uniform_,xavier_uniform_,normal_
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# %% ../nbs/01_layers.ipynb #325f2936
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def vleaky_relu(input, inplace=True):
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"`F.leaky_relu` with 0.3 slope"
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return F.leaky_relu(input, negative_slope=0.3, inplace=inplace)
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# %% ../nbs/01_layers.ipynb #2085d283
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for o in F.relu,nn.ReLU,F.relu6,nn.ReLU6,F.leaky_relu,nn.LeakyReLU:
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o.__default_init__ = kaiming_uniform_
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# %% ../nbs/01_layers.ipynb #32277816
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for o in F.sigmoid,nn.Sigmoid,F.tanh,nn.Tanh,sigmoid,sigmoid_:
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o.__default_init__ = xavier_uniform_
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# %% ../nbs/01_layers.ipynb #addd4cb9
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def init_default(m, func=nn.init.kaiming_normal_):
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"Initialize `m` weights with `func` and set `bias` to 0."
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if func and hasattr(m, 'weight'): func(m.weight)
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with torch.no_grad(): nested_callable(m, 'bias.fill_')(0.)
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return m
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# %% ../nbs/01_layers.ipynb #de95e509
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def init_linear(m, act_func=None, init='auto', bias_std=0.01):
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if getattr(m,'bias',None) is not None and bias_std is not None:
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if bias_std != 0: normal_(m.bias, 0, bias_std)
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else: m.bias.data.zero_()
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if init=='auto':
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if act_func in (F.relu_,F.leaky_relu_): init = kaiming_uniform_
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else: init = nested_callable(act_func, '__class__.__default_init__')
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if init == noop: init = getcallable(act_func, '__default_init__')
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if callable(init): init(m.weight)
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# %% ../nbs/01_layers.ipynb #e6800585
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def _conv_func(ndim=2, transpose=False):
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"Return the proper conv `ndim` function, potentially `transposed`."
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assert 1 <= ndim <=3
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return getattr(nn, f'Conv{"Transpose" if transpose else ""}{ndim}d')
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# %% ../nbs/01_layers.ipynb #3e75b25f
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defaults.activation=nn.ReLU
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# %% ../nbs/01_layers.ipynb #56f79d71
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class ConvLayer(nn.Sequential):
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"Create a sequence of convolutional (`ni` to `nf`), ReLU (if `use_activ`) and `norm_type` layers."
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@delegates(nn.Conv2d)
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def __init__(self, ni, nf, ks=3, stride=1, padding=None, bias=None, ndim=2, norm_type=NormType.Batch, bn_1st=True,
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act_cls=defaults.activation, transpose=False, init='auto', xtra=None, bias_std=0.01, **kwargs):
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if padding is None: padding = ((ks-1)//2 if not transpose else 0)
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bn = norm_type in (NormType.Batch, NormType.BatchZero)
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inn = norm_type in (NormType.Instance, NormType.InstanceZero)
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if bias is None: bias = not (bn or inn)
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conv_func = _conv_func(ndim, transpose=transpose)
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conv = conv_func(ni, nf, kernel_size=ks, bias=bias, stride=stride, padding=padding, **kwargs)
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act = None if act_cls is None else act_cls()
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init_linear(conv, act, init=init, bias_std=bias_std)
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if norm_type==NormType.Weight: conv = weight_norm(conv)
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elif norm_type==NormType.Spectral: conv = spectral_norm(conv)
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layers = [conv]
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act_bn = []
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if act is not None: act_bn.append(act)
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if bn: act_bn.append(BatchNorm(nf, norm_type=norm_type, ndim=ndim))
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if inn: act_bn.append(InstanceNorm(nf, norm_type=norm_type, ndim=ndim))
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if bn_1st: act_bn.reverse()
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layers += act_bn
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if xtra: layers.append(xtra)
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super().__init__(*layers)
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# %% ../nbs/01_layers.ipynb #6d29cf74
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def AdaptiveAvgPool(sz=1, ndim=2):
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"nn.AdaptiveAvgPool layer for `ndim`"
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assert 1 <= ndim <= 3
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return getattr(nn, f"AdaptiveAvgPool{ndim}d")(sz)
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# %% ../nbs/01_layers.ipynb #aba89a55
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def MaxPool(ks=2, stride=None, padding=0, ndim=2, ceil_mode=False):
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"nn.MaxPool layer for `ndim`"
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assert 1 <= ndim <= 3
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return getattr(nn, f"MaxPool{ndim}d")(ks, stride=stride, padding=padding)
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# %% ../nbs/01_layers.ipynb #2064935d
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def AvgPool(ks=2, stride=None, padding=0, ndim=2, ceil_mode=False):
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"nn.AvgPool layer for `ndim`"
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assert 1 <= ndim <= 3
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return getattr(nn, f"AvgPool{ndim}d")(ks, stride=stride, padding=padding, ceil_mode=ceil_mode)
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# %% ../nbs/01_layers.ipynb #23f4e092
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def trunc_normal_(x, mean=0., std=1.):
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"Truncated normal initialization (approximation)"
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# From https://discuss.pytorch.org/t/implementing-truncated-normal-initializer/4778/12
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return x.normal_().fmod_(2).mul_(std).add_(mean)
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# %% ../nbs/01_layers.ipynb #8da76256
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class Embedding(nn.Embedding):
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"Embedding layer with truncated normal initialization"
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def __init__(self, ni, nf, std=0.01):
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super().__init__(ni, nf)
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trunc_normal_(self.weight.data, std=std)
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# %% ../nbs/01_layers.ipynb #2203ab21
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class SelfAttention(Module):
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"Self attention layer for `n_channels`."
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def __init__(self, n_channels):
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self.query,self.key,self.value = [self._conv(n_channels, c) for c in (n_channels//8,n_channels//8,n_channels)]
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self.gamma = nn.Parameter(tensor([0.]))
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def _conv(self,n_in,n_out):
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return ConvLayer(n_in, n_out, ks=1, ndim=1, norm_type=NormType.Spectral, act_cls=None, bias=False)
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def forward(self, x):
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#Notation from the paper.
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size = x.size()
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x = x.view(*size[:2],-1)
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f,g,h = self.query(x),self.key(x),self.value(x)
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beta = F.softmax(torch.bmm(f.transpose(1,2), g), dim=1)
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o = self.gamma * torch.bmm(h, beta) + x
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return o.view(*size).contiguous()
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# %% ../nbs/01_layers.ipynb #84fd5d1f
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class PooledSelfAttention2d(Module):
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"Pooled self attention layer for 2d."
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def __init__(self, n_channels):
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self.n_channels = n_channels
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self.query,self.key,self.value = [self._conv(n_channels, c) for c in (n_channels//8,n_channels//8,n_channels//2)]
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self.out = self._conv(n_channels//2, n_channels)
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self.gamma = nn.Parameter(tensor([0.]))
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def _conv(self,n_in,n_out):
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return ConvLayer(n_in, n_out, ks=1, norm_type=NormType.Spectral, act_cls=None, bias=False)
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def forward(self, x):
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n_ftrs = x.shape[2]*x.shape[3]
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f = self.query(x).view(-1, self.n_channels//8, n_ftrs)
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g = F.max_pool2d(self.key(x), [2,2]).view(-1, self.n_channels//8, n_ftrs//4)
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h = F.max_pool2d(self.value(x), [2,2]).view(-1, self.n_channels//2, n_ftrs//4)
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beta = F.softmax(torch.bmm(f.transpose(1, 2), g), -1)
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o = self.out(torch.bmm(h, beta.transpose(1,2)).view(-1, self.n_channels//2, x.shape[2], x.shape[3]))
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return self.gamma * o + x
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# %% ../nbs/01_layers.ipynb #65612085
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def _conv1d_spect(ni:int, no:int, ks:int=1, stride:int=1, padding:int=0, bias:bool=False):
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"Create and initialize a `nn.Conv1d` layer with spectral normalization."
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conv = nn.Conv1d(ni, no, ks, stride=stride, padding=padding, bias=bias)
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nn.init.kaiming_normal_(conv.weight)
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if bias: conv.bias.data.zero_()
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return spectral_norm(conv)
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# %% ../nbs/01_layers.ipynb #09394290
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class SimpleSelfAttention(Module):
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def __init__(self, n_in:int, ks=1, sym=False):
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self.sym,self.n_in = sym,n_in
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self.conv = _conv1d_spect(n_in, n_in, ks, padding=ks//2, bias=False)
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self.gamma = nn.Parameter(tensor([0.]))
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def forward(self,x):
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if self.sym:
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c = self.conv.weight.view(self.n_in,self.n_in)
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c = (c + c.t())/2
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self.conv.weight = c.view(self.n_in,self.n_in,1)
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size = x.size()
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x = x.view(*size[:2],-1)
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convx = self.conv(x)
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xxT = torch.bmm(x,x.permute(0,2,1).contiguous())
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o = torch.bmm(xxT, convx)
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o = self.gamma * o + x
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return o.view(*size).contiguous()
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# %% ../nbs/01_layers.ipynb #b9d70267
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def icnr_init(x, scale=2, init=nn.init.kaiming_normal_):
|
|
"ICNR init of `x`, with `scale` and `init` function"
|
|
ni,nf,h,w = x.shape
|
|
ni2 = int(ni/(scale**2))
|
|
k = init(x.new_zeros([ni2,nf,h,w])).transpose(0, 1)
|
|
k = k.contiguous().view(ni2, nf, -1)
|
|
k = k.repeat(1, 1, scale**2)
|
|
return k.contiguous().view([nf,ni,h,w]).transpose(0, 1)
|
|
|
|
# %% ../nbs/01_layers.ipynb #e4ecfb86
|
|
class PixelShuffle_ICNR(nn.Sequential):
|
|
"Upsample by `scale` from `ni` filters to `nf` (default `ni`), using `nn.PixelShuffle`."
|
|
def __init__(self, ni, nf=None, scale=2, blur=False, norm_type=NormType.Weight, act_cls=defaults.activation):
|
|
super().__init__()
|
|
nf = ifnone(nf, ni)
|
|
layers = [ConvLayer(ni, nf*(scale**2), ks=1, norm_type=norm_type, act_cls=act_cls, bias_std=0),
|
|
nn.PixelShuffle(scale)]
|
|
if norm_type == NormType.Weight:
|
|
layers[0][0].weight_v.data.copy_(icnr_init(layers[0][0].weight_v.data))
|
|
layers[0][0].weight_g.data.copy_(((layers[0][0].weight_v.data**2).sum(dim=[1,2,3])**0.5)[:,None,None,None])
|
|
else:
|
|
layers[0][0].weight.data.copy_(icnr_init(layers[0][0].weight.data))
|
|
if blur: layers += [nn.ReplicationPad2d((1,0,1,0)), nn.AvgPool2d(2, stride=1)]
|
|
super().__init__(*layers)
|
|
|
|
# %% ../nbs/01_layers.ipynb #d7462a79
|
|
def sequential(*args):
|
|
"Create an `nn.Sequential`, wrapping items with `Lambda` if needed"
|
|
if len(args) != 1 or not isinstance(args[0], OrderedDict):
|
|
args = list(args)
|
|
for i,o in enumerate(args):
|
|
if not isinstance(o,nn.Module): args[i] = Lambda(o)
|
|
return nn.Sequential(*args)
|
|
|
|
# %% ../nbs/01_layers.ipynb #ffe2f34c
|
|
class SequentialEx(Module):
|
|
"Like `nn.Sequential`, but with ModuleList semantics, and can access module input"
|
|
def __init__(self, *layers): self.layers = nn.ModuleList(layers)
|
|
|
|
def forward(self, x):
|
|
res = x
|
|
for l in self.layers:
|
|
res.orig = x
|
|
nres = l(res)
|
|
# We have to remove res.orig to avoid hanging refs and therefore memory leaks
|
|
res.orig, nres.orig = None, None
|
|
res = nres
|
|
return res
|
|
|
|
def __getitem__(self,i): return self.layers[i]
|
|
def append(self,l): return self.layers.append(l)
|
|
def extend(self,l): return self.layers.extend(l)
|
|
def insert(self,i,l): return self.layers.insert(i,l)
|
|
|
|
# %% ../nbs/01_layers.ipynb #0361dbb5
|
|
class MergeLayer(Module):
|
|
"Merge a shortcut with the result of the module by adding them or concatenating them if `dense=True`."
|
|
def __init__(self, dense:bool=False): self.dense=dense
|
|
def forward(self, x): return torch.cat([x,x.orig], dim=1) if self.dense else (x+x.orig)
|
|
|
|
# %% ../nbs/01_layers.ipynb #8c08b0de
|
|
class Cat(nn.ModuleList):
|
|
"Concatenate layers outputs over a given dim"
|
|
def __init__(self, layers, dim=1):
|
|
self.dim=dim
|
|
super().__init__(layers)
|
|
def forward(self, x): return torch.cat([l(x) for l in self], dim=self.dim)
|
|
|
|
# %% ../nbs/01_layers.ipynb #7864283f
|
|
class SimpleCNN(nn.Sequential):
|
|
"Create a simple CNN with `filters`."
|
|
def __init__(self, filters, kernel_szs=None, strides=None, bn=True):
|
|
nl = len(filters)-1
|
|
kernel_szs = ifnone(kernel_szs, [3]*nl)
|
|
strides = ifnone(strides , [2]*nl)
|
|
layers = [ConvLayer(filters[i], filters[i+1], kernel_szs[i], stride=strides[i],
|
|
norm_type=(NormType.Batch if bn and i<nl-1 else None)) for i in range(nl)]
|
|
layers.append(PoolFlatten())
|
|
super().__init__(*layers)
|
|
|
|
# %% ../nbs/01_layers.ipynb #77636dfb
|
|
class ProdLayer(Module):
|
|
"Merge a shortcut with the result of the module by multiplying them."
|
|
def forward(self, x): return x * x.orig
|
|
|
|
# %% ../nbs/01_layers.ipynb #d3451548
|
|
inplace_relu = partial(nn.ReLU, inplace=True)
|
|
|
|
# %% ../nbs/01_layers.ipynb #7f78b200
|
|
def SEModule(ch, reduction, act_cls=defaults.activation):
|
|
nf = math.ceil(ch//reduction/8)*8
|
|
return SequentialEx(nn.AdaptiveAvgPool2d(1),
|
|
ConvLayer(ch, nf, ks=1, norm_type=None, act_cls=act_cls),
|
|
ConvLayer(nf, ch, ks=1, norm_type=None, act_cls=nn.Sigmoid),
|
|
ProdLayer())
|
|
|
|
# %% ../nbs/01_layers.ipynb #41222e11
|
|
class ResBlock(Module):
|
|
"Resnet block from `ni` to `nh` with `stride`"
|
|
@delegates(ConvLayer.__init__)
|
|
def __init__(self, expansion, ni, nf, stride=1, groups=1, reduction=None, nh1=None, nh2=None, dw=False, g2=1,
|
|
sa=False, sym=False, norm_type=NormType.Batch, act_cls=defaults.activation, ndim=2, ks=3,
|
|
pool=AvgPool, pool_first=True, **kwargs):
|
|
norm2 = (NormType.BatchZero if norm_type==NormType.Batch else
|
|
NormType.InstanceZero if norm_type==NormType.Instance else norm_type)
|
|
if nh2 is None: nh2 = nf
|
|
if nh1 is None: nh1 = nh2
|
|
nf,ni = nf*expansion,ni*expansion
|
|
k0 = dict(norm_type=norm_type, act_cls=act_cls, ndim=ndim, **kwargs)
|
|
k1 = dict(norm_type=norm2, act_cls=None, ndim=ndim, **kwargs)
|
|
convpath = [ConvLayer(ni, nh2, ks, stride=stride, groups=ni if dw else groups, **k0),
|
|
ConvLayer(nh2, nf, ks, groups=g2, **k1)
|
|
] if expansion == 1 else [
|
|
ConvLayer(ni, nh1, 1, **k0),
|
|
ConvLayer(nh1, nh2, ks, stride=stride, groups=nh1 if dw else groups, **k0),
|
|
ConvLayer(nh2, nf, 1, groups=g2, **k1)]
|
|
if reduction: convpath.append(SEModule(nf, reduction=reduction, act_cls=act_cls))
|
|
if sa: convpath.append(SimpleSelfAttention(nf,ks=1,sym=sym))
|
|
self.convpath = nn.Sequential(*convpath)
|
|
idpath = []
|
|
if ni!=nf: idpath.append(ConvLayer(ni, nf, 1, act_cls=None, ndim=ndim, **kwargs))
|
|
if stride!=1: idpath.insert((1,0)[pool_first], pool(stride, ndim=ndim, ceil_mode=True))
|
|
self.idpath = nn.Sequential(*idpath)
|
|
self.act = defaults.activation(inplace=True) if act_cls is defaults.activation else act_cls()
|
|
|
|
def forward(self, x): return self.act(self.convpath(x) + self.idpath(x))
|
|
|
|
# %% ../nbs/01_layers.ipynb #fc383839
|
|
def SEBlock(expansion, ni, nf, groups=1, reduction=16, stride=1, **kwargs):
|
|
return ResBlock(expansion, ni, nf, stride=stride, groups=groups, reduction=reduction, nh1=nf*2, nh2=nf*expansion, **kwargs)
|
|
|
|
# %% ../nbs/01_layers.ipynb #20b0934f
|
|
def SEResNeXtBlock(expansion, ni, nf, groups=32, reduction=16, stride=1, base_width=4, **kwargs):
|
|
w = math.floor(nf * (base_width / 64)) * groups
|
|
return ResBlock(expansion, ni, nf, stride=stride, groups=groups, reduction=reduction, nh2=w, **kwargs)
|
|
|
|
# %% ../nbs/01_layers.ipynb #d24dd98e
|
|
def SeparableBlock(expansion, ni, nf, reduction=16, stride=1, base_width=4, **kwargs):
|
|
return ResBlock(expansion, ni, nf, stride=stride, reduction=reduction, nh2=nf*2, dw=True, **kwargs)
|
|
|
|
# %% ../nbs/01_layers.ipynb #46922dc7
|
|
def _stack_tups(tuples, stack_dim=1):
|
|
"Stack tuple of tensors along `stack_dim`"
|
|
return tuple(torch.stack([t[i] for t in tuples], dim=stack_dim) for i in range_of(tuples[0]))
|
|
|
|
# %% ../nbs/01_layers.ipynb #0ce0ec01
|
|
class TimeDistributed(Module):
|
|
"Applies `module` over `tdim` identically for each step, use `low_mem` to compute one at a time."
|
|
def __init__(self, module, low_mem=False, tdim=1):
|
|
store_attr()
|
|
|
|
def forward(self, *tensors, **kwargs):
|
|
"input x with shape:(bs,seq_len,channels,width,height)"
|
|
if self.low_mem or self.tdim!=1:
|
|
return self.low_mem_forward(*tensors, **kwargs)
|
|
else:
|
|
#only support tdim=1
|
|
inp_shape = tensors[0].shape
|
|
bs, seq_len = inp_shape[0], inp_shape[1]
|
|
out = self.module(*[x.view(bs*seq_len, *x.shape[2:]) for x in tensors], **kwargs)
|
|
return self.format_output(out, bs, seq_len)
|
|
|
|
def low_mem_forward(self, *tensors, **kwargs):
|
|
"input x with shape:(bs,seq_len,channels,width,height)"
|
|
seq_len = tensors[0].shape[self.tdim]
|
|
args_split = [torch.unbind(x, dim=self.tdim) for x in tensors]
|
|
out = []
|
|
for i in range(seq_len):
|
|
out.append(self.module(*[args[i] for args in args_split]), **kwargs)
|
|
if isinstance(out[0], tuple):
|
|
return _stack_tups(out, stack_dim=self.tdim)
|
|
return torch.stack(out, dim=self.tdim)
|
|
|
|
def format_output(self, out, bs, seq_len):
|
|
"unstack from batchsize outputs"
|
|
if isinstance(out, tuple):
|
|
return tuple(out_i.view(bs, seq_len, *out_i.shape[1:]) for out_i in out)
|
|
return out.view(bs, seq_len,*out.shape[1:])
|
|
|
|
def __repr__(self):
|
|
return f'TimeDistributed({self.module})'
|
|
|
|
# %% ../nbs/01_layers.ipynb #b574069f
|
|
from torch.jit import script
|
|
|
|
# %% ../nbs/01_layers.ipynb #ebf842f4
|
|
@script
|
|
def _swish_jit_fwd(x): return x.mul(torch.sigmoid(x))
|
|
|
|
@script
|
|
def _swish_jit_bwd(x, grad_output):
|
|
x_sigmoid = torch.sigmoid(x)
|
|
return grad_output * (x_sigmoid * (1 + x * (1 - x_sigmoid)))
|
|
|
|
class _SwishJitAutoFn(torch.autograd.Function):
|
|
@staticmethod
|
|
def forward(ctx, x):
|
|
ctx.save_for_backward(x)
|
|
return _swish_jit_fwd(x)
|
|
|
|
@staticmethod
|
|
def backward(ctx, grad_output):
|
|
x = ctx.saved_variables[0]
|
|
return _swish_jit_bwd(x, grad_output)
|
|
|
|
# %% ../nbs/01_layers.ipynb #58c329c4
|
|
def swish(x, inplace=False): F.silu(x, inplace=inplace)
|
|
|
|
# %% ../nbs/01_layers.ipynb #68aa98c3
|
|
class SwishJit(Module):
|
|
def forward(self, x): return _SwishJitAutoFn.apply(x)
|
|
|
|
# %% ../nbs/01_layers.ipynb #25af1caa
|
|
@script
|
|
def _mish_jit_fwd(x): return x.mul(torch.tanh(F.softplus(x)))
|
|
|
|
@script
|
|
def _mish_jit_bwd(x, grad_output):
|
|
x_sigmoid = torch.sigmoid(x)
|
|
x_tanh_sp = F.softplus(x).tanh()
|
|
return grad_output.mul(x_tanh_sp + x * x_sigmoid * (1 - x_tanh_sp * x_tanh_sp))
|
|
|
|
class MishJitAutoFn(torch.autograd.Function):
|
|
@staticmethod
|
|
def forward(ctx, x):
|
|
ctx.save_for_backward(x)
|
|
return _mish_jit_fwd(x)
|
|
|
|
@staticmethod
|
|
def backward(ctx, grad_output):
|
|
x = ctx.saved_variables[0]
|
|
return _mish_jit_bwd(x, grad_output)
|
|
|
|
# %% ../nbs/01_layers.ipynb #6045af6e
|
|
def mish(x, inplace=False): return F.mish(x, inplace=inplace)
|
|
|
|
# %% ../nbs/01_layers.ipynb #255c3485
|
|
class MishJit(Module):
|
|
def forward(self, x): return MishJitAutoFn.apply(x)
|
|
|
|
# %% ../nbs/01_layers.ipynb #5da4007d
|
|
Mish = nn.Mish
|
|
Swish = nn.SiLU
|
|
|
|
# %% ../nbs/01_layers.ipynb #819daafd
|
|
for o in swish,Swish,SwishJit,mish,Mish,MishJit: o.__default_init__ = kaiming_uniform_
|
|
|
|
# %% ../nbs/01_layers.ipynb #6278d60f
|
|
class ParameterModule(Module):
|
|
"Register a lone parameter `p` in a module."
|
|
def __init__(self, p): self.val = p
|
|
def forward(self, x): return x
|
|
|
|
# %% ../nbs/01_layers.ipynb #f01f78cd
|
|
def children_and_parameters(m):
|
|
"Return the children of `m` and its direct parameters not registered in modules."
|
|
children = list(m.children())
|
|
children_p = sum([[id(p) for p in c.parameters()] for c in m.children()],[])
|
|
for p in m.parameters():
|
|
if id(p) not in children_p: children.append(ParameterModule(p))
|
|
return children
|
|
|
|
# %% ../nbs/01_layers.ipynb #f011d211
|
|
def has_children(m):
|
|
try: next(m.children())
|
|
except StopIteration: return False
|
|
return True
|
|
|
|
# %% ../nbs/01_layers.ipynb #67c64b8f
|
|
def flatten_model(m):
|
|
"Return the list of all submodules and parameters of `m`"
|
|
return sum(map(flatten_model,children_and_parameters(m)),[]) if has_children(m) else [m]
|
|
|
|
# %% ../nbs/01_layers.ipynb #9dc13b7e
|
|
class NoneReduce():
|
|
"A context manager to evaluate `loss_func` with none reduce."
|
|
def __init__(self, loss_func): self.loss_func,self.old_red = loss_func,None
|
|
|
|
def __enter__(self):
|
|
if hasattr(self.loss_func, 'reduction'):
|
|
self.old_red = self.loss_func.reduction
|
|
self.loss_func.reduction = 'none'
|
|
return self.loss_func
|
|
else: return partial(self.loss_func, reduction='none')
|
|
|
|
def __exit__(self, type, value, traceback):
|
|
if self.old_red is not None: self.loss_func.reduction = self.old_red
|
|
|
|
# %% ../nbs/01_layers.ipynb #14782381
|
|
def in_channels(m):
|
|
"Return the shape of the first weight layer in `m`."
|
|
try: return next(l.weight.shape[1] for l in flatten_model(m) if nested_attr(l,'weight.ndim',-1)==4)
|
|
except StopIteration as e: e.args = ["No weight layer"]; raise
|