1
0
Fork 0
mirror of https://github.com/deepfakes/faceswap synced 2025-06-07 19:05:02 -04:00
faceswap/lib/model/initializers.py
torzdf aa39234538
Update all Keras Imports to be conditional (#1214)
* Remove custom keras importer

* first round keras imports fix

* launcher.py: Remove KerasFinder references

* 2nd round keras imports update (lib and extract)

* 3rd round keras imports update (train)

* remove KerasFinder from tests

* 4th round keras imports update (tests)
2022-05-03 20:18:39 +01:00

328 lines
12 KiB
Python

#!/usr/bin/env python3
""" Custom Initializers for faceswap.py """
import logging
import sys
import inspect
import numpy as np
import tensorflow as tf
from lib.utils import get_backend
if get_backend() == "amd":
from keras.utils import get_custom_objects # pylint:disable=no-name-in-module
from keras import backend as K
from keras import initializers
else:
# Ignore linting errors from Tensorflow's thoroughly broken import system
from tensorflow.keras.utils import get_custom_objects # noqa pylint:disable=no-name-in-module,import-error
from tensorflow.keras import initializers, backend as K # noqa pylint:disable=no-name-in-module,import-error
logger = logging.getLogger(__name__) # pylint: disable=invalid-name
def compute_fans(shape, data_format='channels_last'):
"""Computes the number of input and output units for a weight shape.
Ported directly from Keras as the location moves between keras and tensorflow-keras
Parameters
----------
shape: tuple
shape tuple of integers
data_format: str
Image data format to use for convolution kernels. Note that all kernels in Keras are
standardized on the `"channels_last"` ordering (even when inputs are set to
`"channels_first"`).
Returns
-------
tuple
A tuple of scalars, `(fan_in, fan_out)`.
Raises
------
ValueError
In case of invalid `data_format` argument.
"""
if len(shape) == 2:
fan_in = shape[0]
fan_out = shape[1]
elif len(shape) in {3, 4, 5}:
# Assuming convolution kernels (1D, 2D or 3D).
# Theano kernel shape: (depth, input_depth, ...)
# Tensorflow kernel shape: (..., input_depth, depth)
if data_format == 'channels_first':
receptive_field_size = np.prod(shape[2:])
fan_in = shape[1] * receptive_field_size
fan_out = shape[0] * receptive_field_size
elif data_format == 'channels_last':
receptive_field_size = np.prod(shape[:-2])
fan_in = shape[-2] * receptive_field_size
fan_out = shape[-1] * receptive_field_size
else:
raise ValueError('Invalid data_format: ' + data_format)
else:
# No specific assumptions.
fan_in = np.sqrt(np.prod(shape))
fan_out = np.sqrt(np.prod(shape))
return fan_in, fan_out
class ICNR(initializers.Initializer): # pylint: disable=invalid-name,no-member
""" ICNR initializer for checkerboard artifact free sub pixel convolution
Parameters
----------
initializer: :class:`keras.initializers.Initializer`
The initializer used for sub kernels (orthogonal, glorot uniform, etc.)
scale: int, optional
scaling factor of sub pixel convolution (up sampling from 8x8 to 16x16 is scale 2).
Default: `2`
Returns
-------
tensor
The modified kernel weights
Example
-------
>>> x = conv2d(... weights_initializer=ICNR(initializer=he_uniform(), scale=2))
References
----------
Andrew Aitken et al. Checkerboard artifact free sub-pixel convolution
https://arxiv.org/pdf/1707.02937.pdf, https://distill.pub/2016/deconv-checkerboard/
"""
def __init__(self, initializer, scale=2):
self.scale = scale
self.initializer = initializer
def __call__(self, shape, dtype="float32"):
""" Call function for the ICNR initializer.
Parameters
----------
shape: tuple or list
The required resized shape for the output tensor
dtype: str
The data type for the tensor
Returns
-------
tensor
The modified kernel weights
"""
shape = list(shape)
if self.scale == 1:
return self.initializer(shape)
new_shape = shape[:3] + [shape[3] // (self.scale ** 2)]
if isinstance(self.initializer, dict):
self.initializer = initializers.deserialize(self.initializer)
var_x = self.initializer(new_shape, dtype)
var_x = K.permute_dimensions(var_x, [2, 0, 1, 3])
var_x = K.resize_images(var_x,
self.scale,
self.scale,
"channels_last",
interpolation="nearest")
var_x = self._space_to_depth(var_x)
var_x = K.permute_dimensions(var_x, [1, 2, 0, 3])
logger.debug("Output shape: %s", var_x.shape)
return var_x
def _space_to_depth(self, input_tensor):
""" Space to depth implementation.
PlaidML does not have a space to depth operation, so calculate if backend is amd
otherwise returns the :func:`tensorflow.space_to_depth` operation.
Parameters
----------
input_tensor: tensor
The tensor to be manipulated
Returns
-------
tensor
The manipulated input tensor
"""
if get_backend() == "amd":
batch, height, width, depth = input_tensor.shape.dims
new_height = height // self.scale
new_width = width // self.scale
reshaped = K.reshape(input_tensor,
(batch, new_height, self.scale, new_width, self.scale, depth))
retval = K.reshape(K.permute_dimensions(reshaped, [0, 1, 3, 2, 4, 5]),
(batch, new_height, new_width, -1))
else:
retval = tf.nn.space_to_depth(input_tensor, block_size=self.scale, data_format="NHWC")
logger.debug("Input shape: %s, Output shape: %s", input_tensor.shape, retval.shape)
return retval
def get_config(self):
""" Return the ICNR Initializer configuration.
Returns
-------
dict
The configuration for ICNR Initialization
"""
config = {"scale": self.scale,
"initializer": self.initializer
}
base_config = super().get_config()
return dict(list(base_config.items()) + list(config.items()))
class ConvolutionAware(initializers.Initializer): # pylint: disable=no-member
"""
Initializer that generates orthogonal convolution filters in the Fourier space. If this
initializer is passed a shape that is not 3D or 4D, orthogonal initialization will be used.
Adapted, fixed and optimized from:
https://github.com/keras-team/keras-contrib/blob/master/keras_contrib/initializers/convaware.py
Parameters
----------
eps_std: float, optional
The Standard deviation for the random normal noise used to break symmetry in the inverse
Fourier transform. Default: 0.05
seed: int, optional
Used to seed the random generator. Default: ``None``
initialized: bool, optional
This should always be set to ``False``. To avoid Keras re-calculating the values every time
the model is loaded, this parameter is internally set on first time initialization.
Default:``False``
Returns
-------
tensor
The modified kernel weights
References
----------
Armen Aghajanyan, https://arxiv.org/abs/1702.06295
"""
def __init__(self, eps_std=0.05, seed=None, initialized=False):
self.eps_std = eps_std
self.seed = seed
self.orthogonal = initializers.Orthogonal() # pylint:disable=no-member
self.he_uniform = initializers.he_uniform() # pylint:disable=no-member
self.initialized = initialized
def __call__(self, shape, dtype=None):
""" Call function for the ICNR initializer.
Parameters
----------
shape: tuple or list
The required shape for the output tensor
dtype: str
The data type for the tensor
Returns
-------
tensor
The modified kernel weights
"""
# TODO Tensorflow appears to pass in a :class:`tensorflow.python.framework.dtypes.DType`
# object which causes this to error, so currently just reverts to default dtype if a string
# is not passed in.
if self.initialized: # Avoid re-calculating initializer when loading a saved model
return self.he_uniform(shape, dtype=dtype)
dtype = K.floatx() if not isinstance(dtype, str) else dtype
logger.info("Calculating Convolution Aware Initializer for shape: %s", shape)
rank = len(shape)
if self.seed is not None:
np.random.seed(self.seed)
fan_in, _ = compute_fans(shape) # pylint:disable=protected-access
variance = 2 / fan_in
if rank == 3:
row, stack_size, filters_size = shape
transpose_dimensions = (2, 1, 0)
kernel_shape = (row,)
correct_ifft = lambda shape, s=[None]: np.fft.irfft(shape, s[0]) # noqa
correct_fft = np.fft.rfft
elif rank == 4:
row, column, stack_size, filters_size = shape
transpose_dimensions = (2, 3, 1, 0)
kernel_shape = (row, column)
correct_ifft = np.fft.irfft2
correct_fft = np.fft.rfft2
elif rank == 5:
var_x, var_y, var_z, stack_size, filters_size = shape
transpose_dimensions = (3, 4, 0, 1, 2)
kernel_shape = (var_x, var_y, var_z)
correct_fft = np.fft.rfftn
correct_ifft = np.fft.irfftn
else:
self.initialized = True
return K.variable(self.orthogonal(shape), dtype=dtype)
kernel_fourier_shape = correct_fft(np.zeros(kernel_shape)).shape
basis = self._create_basis(filters_size, stack_size, np.prod(kernel_fourier_shape), dtype)
basis = basis.reshape((filters_size, stack_size,) + kernel_fourier_shape)
randoms = np.random.normal(0, self.eps_std, basis.shape[:-2] + kernel_shape)
init = correct_ifft(basis, kernel_shape) + randoms
init = self._scale_filters(init, variance)
self.initialized = True
return K.variable(init.transpose(transpose_dimensions), dtype=dtype, name="conv_aware")
def _create_basis(self, filters_size, filters, size, dtype):
""" Create the basis for convolutional aware initialization """
logger.debug("filters_size: %s, filters: %s, size: %s, dtype: %s",
filters_size, filters, size, dtype)
if size == 1:
return np.random.normal(0.0, self.eps_std, (filters_size, filters, size))
nbb = filters // size + 1
var_a = np.random.normal(0.0, 1.0, (filters_size, nbb, size, size))
var_a = self._symmetrize(var_a)
var_u = np.linalg.svd(var_a)[0].transpose(0, 1, 3, 2)
var_p = np.reshape(var_u, (filters_size, nbb * size, size))[:, :filters, :].astype(dtype)
return var_p
@staticmethod
def _symmetrize(var_a):
""" Make the given tensor symmetrical. """
var_b = np.transpose(var_a, axes=(0, 1, 3, 2))
diag = var_a.diagonal(axis1=2, axis2=3)
var_c = np.array([[np.diag(arr) for arr in batch] for batch in diag])
return var_a + var_b - var_c
@staticmethod
def _scale_filters(filters, variance):
""" Scale the given filters. """
c_var = np.var(filters)
var_p = np.sqrt(variance / c_var)
return filters * var_p
def get_config(self):
""" Return the Convolutional Aware Initializer configuration.
Returns
-------
dict
The configuration for ICNR Initialization
"""
return dict(eps_std=self.eps_std,
seed=self.seed,
initialized=self.initialized)
# Update initializers into Keras custom objects
for name, obj in inspect.getmembers(sys.modules[__name__]):
if inspect.isclass(obj) and obj.__module__ == __name__:
get_custom_objects().update({name: obj})