def batch_matmul(X, Y):
"""Keras-only implementation of tensorflow's batch matmul behavior in tf.matmul()"""
with K.name_scope('batch_matmul'):
x_shape = K.shape(X)
y_shape = K.shape(Y)
x_leading_dims = x_shape[:-2]
y_leading_dims = y_shape[:-2]
x_mat_dims = x_shape[-2:]
y_mat_dims = y_shape[-2:]
x_flatten_dim = K.prod(x_leading_dims, keepdims=True)
y_flatten_dim = K.prod(y_leading_dims, keepdims=True)
x_reshape_dims = K.concatenate([x_flatten_dim, x_mat_dims])
y_reshape_dims = K.concatenate([y_flatten_dim, y_mat_dims])
product_dims = K.concatenate(
[x_leading_dims, x_mat_dims[:1], y_mat_dims[1:]])
X = K.reshape(X, x_reshape_dims)
Y = K.reshape(Y, y_reshape_dims)
prod = K.batch_dot(X, Y)
return K.reshape(prod, product_dims)
def _thoracic_loss(y_pred, eta, p, bbox, lambda_bbox=0.5):
# y_predis a PxP tensor, input img is a 512x512 tensor
# bbox=(xa,wa,ya,ha)
lambda_bbox = 0.5
# p2 = K.ones_like(y_pred) - y_pred
p2 = 1 - y_pred
# p_y_x = 1-tf.reduce_prod(p2)
p_y_x = 1 - K.prod(p2)
P = K.cast(K.shape(y_pred)[1], 'float')
x = bbox[0][0] * P / float(512)
y = bbox[0][1] * P / float(512)
w = bbox[0][2] * P / float(512)
h = bbox[0][3] * P / float(512)
x = K.cast(x, 'int32')
y = K.cast(y, 'int32')
w = K.cast(w, 'int32')
h = K.cast(h, 'int32')
in_box = y_pred[:, y:y + h, x:x + w]
p1 = K.prod(in_box)
p3 = K.prod(1 - in_box)
p2 = K.prod(y_pred)
p_y_x_bbox = p3 * p2 / p1
loss = -eta * K.log(p_y_x_bbox) - (1 - eta) * p * K.log(p_y_x) - (
1 - eta) * (1 - p) * K.log(1 - p_y_x)
print(loss)
return loss
def generalizedDiceLoss(y_true, y_pred):
# GDL, reference: https://arxiv.org/pdf/1707.03237.pdf
# Sudre et al, 2017, ArXiv (Generalised DICE overlap as a deep learning loss function for highly unbalanced segmentations)
# DICE Loss for multi-category classification
_EPSILON = K.epsilon()
y_pred = K.clip(y_pred, _EPSILON, 1.0 - _EPSILON)
y_true = K.clip(y_true, _EPSILON, 1.0 - _EPSILON)
# First flatten the matrices for each channel (category)
ypredshape = y_pred.get_shape().as_list()
ytrueshape = y_true.get_shape().as_list()
dimp = K.prod(K.shape(y_pred)[:-1])
dimt = K.prod(K.shape(y_true)[:-1])
y_pred = K.reshape(y_pred, (dimp, ypredshape[-1]))
y_true = K.reshape(y_true, (dimt, -1))
y_int = y_pred * y_true
# Prevent dividing by 0
# square over the flattened axis
weights = 1 / (K.square(K.sum(y_true, axis=0)))
numerator = 2 * K.sum(weights * K.sum(y_int, axis=0), axis=-1)
denominator = K.sum(
weights *
(K.sum(K.square(y_true), axis=0) + K.sum(K.square(y_pred), axis=0)),
axis=-1)
loss = -numerator / denominator
return loss
def loss(y_true, y_pred):
# Gaussian normalization factor
normalization_factor = 1 / sqrt(2 * pi * var)
# Calculate old pdf
old_exponent = -K.square(actions - y_true) / (2. * var)
old_pdf = K.prod(normalization_factor * K.exp(old_exponent), axis=-1)
# Calculate new pdf
exponent = -K.square(actions - y_pred) / (2. * var)
pdf = K.prod(normalization_factor * K.exp(exponent), axis=-1)
# Calculate ratio and clipped ratio
pdf_ratio = pdf / old_pdf
clipped_pdf_ratio = K.clip(pdf_ratio, 1 - loss_clipping_epsilon,
1 + loss_clipping_epsilon)
# Get clipped loss
# Notice the minus sign. Since we want to maximize the
# objective, we need to minimize the negative objective.
clipped_loss = -K.minimum(pdf_ratio * advantages,
clipped_pdf_ratio * advantages)
return clipped_loss
def soft_mask_mean_absolute_error_with_total(y_true, y_pred):
y_pred_tot = K.sum(K.prod([y_pred[:, :, :, 0], y_pred[:, :, :, 1]],
axis=(1, 2)),
axis=(1, 2))
y_true_tot = K.sum(K.prod([y_true[:, :, :, 0], y_true[:, :, :, 1]],
axis=(1, 2)),
axis=(1, 2))
return soft_mask_mean_absolute_error(
y_true, y_pred) + 0.5 * K.mean(K.abs(y_pred_tot - y_true_tot))
def sample(inputs, coords, dim, wrapped):
"""
sample - samples from the inputs tensor using coords as indices.
:param inputs: the tensor to sample from
shape: (N, width, height, ..., n_chan)
:param coords: the indices to sample with
shape: (N, dim, width, height, ...)
:param dim: dimensionality of the data, e.g. 2 for 2D images
:param wrapped: whether to wrap out of bound indices or to clip them
"""
inputs_shape = K.shape(inputs)
coords_shape = K.shape(coords)
outputs_shape = K.concatenate(
[inputs_shape[0:1], coords_shape[2:], inputs_shape[-1:]])
maxes = K.cast(inputs_shape[1:-1] - 1, "int32")
if wrapped:
coords = wrap(coords, maxes, dim)
else:
coords = clip(coords, maxes, dim)
if K.backend() == "tensorflow":
return sample_tf(inputs, coords, dim)
n = inputs_shape[0]
n_chan = inputs_shape[-1]
flat_inputs = K.reshape(inputs, (-1, n_chan))
flat_coords = K.flatten(coords[:, -1])
for i in reversed(range(dim - 1)):
flat_coords += K.prod(inputs_shape[1:i + 2]) * K.flatten(coords[:, i])
coords_per_sample = K.prod(coords_shape[2:])
# add the offsets for each sample in the minibatch
if K.backend() == "tensorflow":
import tensorflow as tf
offsets = tf.range(n) * K.prod(inputs_shape[1:-1])
else:
import theano.tensor as T
offsets = T.arange(n) * K.prod(inputs_shape[1:-1])
offsets = K.reshape(offsets, (-1, 1))
offsets = K.tile(offsets, (1, coords_per_sample))
offsets = K.flatten(offsets)
flat_coords += offsets
outputs = K.gather(flat_inputs, flat_coords)
outputs = K.reshape(outputs, outputs_shape)
return outputs
def calc_iou(self, target_regions):
"""
TODO : Write description
calc_iou
"""
pos_tl = KB.maximum(self.__regions[:, None, :2], target_regions[:, :2])
pos_br = KB.maximum(self.__regions[:, None, 2:], target_regions[:, 2:])
t_p = KB.prod(pos_br - pos_tl, axis=2) * KB.cast(
KB.all(pos_br > pos_tl, axis=2), 'float32')
g_t = KB.prod(self.__regions[:, 2:] - self.__regions[:, :2], axis=1)
p_r = KB.prod(target_regions[:, 2:] - target_regions[:, :2], axis=1)
return t_p / (g_t + p_r - t_p)
def mi(y_true, y_pred):
""" soft mutual info """
y_pred = K.clip(y_pred, 0, max_clip)
y_true = K.clip(y_true, 0, max_clip)
if crop_background:
# does not support variable batch size
thresh = 0.0001
padding_size = 20
filt = tf.ones([padding_size, padding_size, padding_size, 1, 1])
smooth = tf.nn.conv3d(y_true, filt, [1, 1, 1, 1, 1], "SAME")
mask = smooth > thresh
# mask = K.any(K.stack([y_true > thresh, y_pred > thresh], axis=0), axis=0)
y_pred = tf.boolean_mask(y_pred, mask)
y_true = tf.boolean_mask(y_true, mask)
y_pred = K.expand_dims(K.expand_dims(y_pred, 0), 2)
y_true = K.expand_dims(K.expand_dims(y_true, 0), 2)
else:
# reshape: flatten images into shape (batch_size, heightxwidthxdepthxchan, 1)
y_true = K.reshape(y_true, (-1, K.prod(K.shape(y_true)[1:])))
y_true = K.expand_dims(y_true, 2)
y_pred = K.reshape(y_pred, (-1, K.prod(K.shape(y_pred)[1:])))
y_pred = K.expand_dims(y_pred, 2)
nb_voxels = tf.cast(K.shape(y_pred)[1], tf.float32)
# reshape bin centers to be (1, 1, B)
o = [1, 1, np.prod(vol_bin_centers.get_shape().as_list())]
vbc = K.reshape(vol_bin_centers, o)
# compute image terms
I_a = K.exp(-preterm * K.square(y_true - vbc))
I_a /= K.sum(I_a, -1, keepdims=True)
I_b = K.exp(-preterm * K.square(y_pred - vbc))
I_b /= K.sum(I_b, -1, keepdims=True)
# compute probabilities
I_a_permute = K.permute_dimensions(I_a, (0, 2, 1))
pab = K.batch_dot(
I_a_permute,
I_b) # should be the right size now, nb_labels x nb_bins
pab /= nb_voxels
pa = tf.reduce_mean(I_a, 1, keep_dims=True)
pb = tf.reduce_mean(I_b, 1, keep_dims=True)
papb = K.batch_dot(K.permute_dimensions(pa,
(0, 2, 1)), pb) + K.epsilon()
mi = K.sum(K.sum(pab * K.log(pab / papb + K.epsilon()), 1), 1)
return mi
def kernel_loss(y_true, y_pred):
inclusion_dist = kb.max(y_pred - 1 + y_true)
exclusion_dist = kb.max(y_pred - y_true)
exclusion_dist2 = kb.mean(y_pred * (1 - y_true) *
kb.cast(y_pred > 0, dtype=kb.floatx()))
# ex_cost = kb.log(exclusion_dist + kb.epsilon()) * (1 - kb.prod(y_true))
# in_cost = -kb.log(inclusion_dist + kb.epsilon()) * (1 - kb.prod(1 - y_true))
ex_cost = (exclusion_dist2 + kb.epsilon()) * (1 - kb.prod(y_true))
in_cost = -(inclusion_dist + kb.epsilon()) * (1 - kb.prod(1 - y_true))
# return inclusion_dist * kb.sum(y_true)
# return - exclusion_dist * (1 - kb.prod(y_true))
return in_cost + ex_cost
def thoracic_loss(self, y_pred, eta, p, bbox, lambda_bbox=0.5):
# Input shape: a list of 4 tensor
# y_pred:(1,P,P)
# eta:(1,1)
# p:(1,1)
# bbox:(1,4) = (xa,wa,ya,ha)
# print(y_pred.shape)
# print(eta.shape)
# print(p.shape)
# print(bbox.shape)
# print
lambda_bbox = 0.5
y_pred = K.minimum(1.0, y_pred)
y_pred_tmp = 1 - y_pred
y_pred_tmp = K.minimum(1.0, y_pred_tmp)
y_pred = y_pred * 0.02 + 0.98 # preform normalization
y_pred_tmp = y_pred_tmp * 0.02 + 0.98 # preform normalization
p_y_x = 1 - K.prod(y_pred_tmp)
P = K.cast(K.shape(y_pred)[1], 'float')
x = bbox[0] * P
y = bbox[1] * P
w = bbox[2] * P
h = bbox[3] * P
x = K.cast(x, 'int32')
y = K.cast(y, 'int32')
w = K.cast(w, 'int32')
h = K.cast(h, 'int32')
# in_box = y_pred[:,y:y+h,x:x+w]
in_box = y_pred[y:y + h, x:x + w]
p1 = K.prod(in_box)
# p3 = K.prod(1.0-in_box)
p3 = K.prod(y_pred_tmp[y:y + h, x:x + w])
# p2 = K.prod(1-y_pred)
p2 = K.prod(y_pred_tmp)
p_y_x_bbox = p1 * p2 / p3 + 1e-10
loss = -eta * K.log(p_y_x_bbox) - (1.0 - eta) * p * K.log(p_y_x) - (
1.0 - eta) * (1.0 - p) * K.log(1.0 - p_y_x)
return loss
def ksparse(x, k, axis, alpha=1, absolute=False):
if isinstance(axis, int):
axis = (axis, )
elif isinstance(axis, list):
axis = tuple(axis)
axis_complement = tuple(set(range(K.ndim(x))) - set(axis))
shape_reduce = K.prod([K.shape(x)[j] for j in axis])
_k = K.minimum(K.in_train_phase(k, alpha * k), shape_reduce)
inputs_permute_dimensions = K.permute_dimensions(x, axis_complement + axis)
inputs_permute_dimensions_reshape = K.reshape(inputs_permute_dimensions,
(-1, shape_reduce))
if absolute is True:
inputs_permute_dimensions_reshape = K.abs(
inputs_permute_dimensions_reshape)
_, indices = tf.nn.top_k(inputs_permute_dimensions_reshape, _k)
scatter_indices = K.concatenate([
(K.arange(K.shape(inputs_permute_dimensions_reshape)[0])[:, None] *
K.ones((1, _k), dtype='int32'))[:, :, None], indices[:, :, None]
])
scatter_updates = K.ones(
(K.shape(inputs_permute_dimensions_reshape)[0], _k))
mask_permute_dimensions_reshape = K.cast(
tf.scatter_nd(scatter_indices, scatter_updates,
K.shape(inputs_permute_dimensions_reshape)), K.floatx())
mask_permute_dimensions = K.reshape(mask_permute_dimensions_reshape,
K.shape(inputs_permute_dimensions))
mask = K.permute_dimensions(mask_permute_dimensions,
tuple(np.argsort(axis_complement + axis)))
return mask * x
def get_single_deconv_out_new(input, filter):
output_shape = (1, 1, input.shape[0]*filter.shape[0], input.shape[1]*filter.shape[1])
# reshape inputs
image = input.reshape((1, K.prod(input.shape)))
kernel = filter.reshape((1, K.prod(filter.shape)))
# neibs = images2neibs(output, neib_shape=filter.shape, neib_step=filter.shape)
def fn(i, k):
return i*k
results, updates = theano.scan(fn=fn, sequences=image[0], non_sequences=kernel[0])
# neibs = neibs*results
img_new = neibs2images(results, filter.shape, output_shape)
return img_new[0][0]
def weighted_mse(y_true, y_pred):
epsilon = 0.000001
pos_mask = K.cast(y_true >= 0.5, 'float32')
neg_mask = K.cast(y_true < -0.5, 'float32')
#y_pred = K.clip(y_pred,epsilon,1-epsilon)
## all labels with absolute value less than 0.01 is background
#pos_mask = K.cast(K.abs(y_true) >= 0.75, 'float32')
#neg_mask = K.cast(K.abs(y_true) < 0.75, 'float32')
num_pixels = K.cast(K.prod(K.shape(y_true)[:]), 'float32')
num_pixels = maybe_print(num_pixels, "total ", do_print=True)
num_pos = maybe_print(K.sum(pos_mask), 'npositive ', do_print=True)
pos_fracs = K.clip((num_pos / num_pixels), 0.05, 0.95)
neg_fracs = K.clip((K.sum(neg_mask) / num_pixels), 0.05, 0.95)
pos_fracs = maybe_print(pos_fracs, "positive fraction", do_print=True)
# chosen to sum to 1 when multiplied by their fractions, assuming no ignore
pos_weight = maybe_print(1.0 / (2 * pos_fracs),
"positive weight",
do_print=True)
neg_weight = maybe_print(1.0 / (2 * neg_fracs),
"negative weight",
do_print=True) #1.25
per_pixel_weights = pos_weight * pos_mask + neg_weight * neg_mask
per_pixel_weighted_sq_error = K.square(y_true - y_pred) * per_pixel_weights
batch_weighted_mse = K.mean(per_pixel_weighted_sq_error) / 1.0
return K.mean(batch_weighted_mse)
def define_loss_fun(model, settings):
dream = model.input
# Get the symbolic outputs of each "key" layer (we gave them unique names).
layer_dict = dict([(layer.name, layer) for layer in model.layers])
# Define the loss.
loss = K.variable(0.)
for layer_name in settings['features']:
# Add the L2 norm of the features of a layer to the loss.
if layer_name not in layer_dict:
raise ValueError('Layer ' + layer_name + ' not found in model.')
coeff = settings['features'][layer_name]
x = layer_dict[layer_name].output
# We avoid border artifacts by only involving non-border pixels in the loss.
scaling = K.prod(K.cast(K.shape(x), 'float32'))
if K.image_data_format() == 'channels_first':
loss += coeff * K.sum(K.square(x[:, :, 2:-2, 2:-2])) / scaling
else:
loss += coeff * K.sum(K.square(x[:, 2:-2, 2:-2, :])) / scaling
# Compute the gradients of the dream wrt the loss.
grads = K.gradients(loss, dream)[0]
# Normalize gradients.
grads /= K.maximum(K.mean(K.abs(grads)), K.epsilon())
# Set up function to retrieve the value
# of the loss and gradients given an input image.
outputs = [loss, grads]
fetch_loss_and_grads = K.function([dream], outputs)
return fetch_loss_and_grads
def siamese_loss(y_true, y_pred):
y_true_ = K.argmax(y_true, axis=-1)
y_true_even = y_true_[::2]
y_true_even = K.expand_dims(y_true_even, axis=-1)
y_true_odd = y_true_[1::2]
y_true_odd = K.expand_dims(y_true_odd, axis=-1)
y_true_ = K.concatenate([y_true_even, y_true_odd], axis=-1)
# label = 1 if dissimilar
labels = K.sum(
y_true_, axis=-1,
keepdims=False) - 2 * K.prod(y_true_, axis=-1, keepdims=False)
labels = K.cast(labels, dtype=K.floatx())
y_pred_even = y_pred[::2, :]
y_pred_odd = y_pred[1::2, :]
l2error = K.sqrt(
K.maximum(
K.sum(K.square(y_pred_even - y_pred_odd), axis=-1, keepdims=False),
K.epsilon()))
contrastive_loss = 0.5 * (
(1 - labels) * K.square(l2error) +
labels * K.square(K.maximum(margin - l2error, 0)))
contrastive_loss = K.expand_dims(contrastive_loss, axis=-1)
contrastive_loss_full = K.concatenate([contrastive_loss, contrastive_loss],
axis=-1)
contrastive_loss_full = K.reshape(contrastive_loss_full, shape=(-1, 1))
contrastive_loss_full = K.squeeze(contrastive_loss_full, axis=-1)
return contrastive_loss_full
def gram_matrix(x, shift = -1):
'''
Batch calculation the gram matrix based on the given input tensor x.
Args:
x (tensor): A 4-tensor of (batch size, img height, img width,
channels)
shift (int): A scalar shifting the activations before calculating
the Gram matrix in the style of
(Novak & Nikulin, 2016)
Returns: The calculated gram matrix.
'''
# Permutes tensor axis (move channels in front)
x = K.permute_dimensions(x, (0, 3, 1, 2))
s = K.shape(x)
# Flatten img dimensions to a single width x height vector
feat = K.reshape(x, (s[0], s[1], s[2] * s[3]))
# Shift the activations before calculating the Gram matrix in the style of
#(Novak & Nikulin, 2016)
feat = feat + shift
# Calculate Gram matrix
gram = K.batch_dot(feat,
K.permute_dimensions(feat, (0, 2, 1))) \
/ K.prod(K.cast(s[1:], K.floatx()))
return gram
def _build_loss(self):
"""
Builds gradient ascent loss
Returns
-------
loss : keras.backend.ops.Tensor
Loss tensor
"""
# Get the symbolic outputs of each "key" layer (we gave them unique names).
layer_dict = dict([(layer.name, layer) for layer in self.model.layers])
# Define the loss.
loss = K.variable(0.)
for layer_name in self.layer_config:
# Add the L2 norm of the features of a layer to the loss.
assert layer_name in layer_dict.keys(
), 'Layer ' + layer_name + ' not found in model.'
# feature map weight
w = self.layer_config[layer_name]
x = layer_dict[layer_name].output
# We avoid border artifacts by only involving non-border pixels in the loss.
scaling = K.prod(K.cast(K.shape(x), 'float32'))
if K.image_data_format() == 'channels_first':
loss += w * K.sum(K.square(x[:, :, 2:-2, 2:-2])) / scaling
else:
loss += w * K.sum(K.square(x[:, 2:-2, 2:-2, :])) / scaling
return loss
def psnr_masked(true, pred):
mask = K.cast(K.not_equal(true, self.config['pad_value']), K.floatx())
return 10. * K.log(
K.cast(
K.sum(1 - K.all(1 - mask, axis=[2, 3, 4]), axis=1) *
K.prod(K.shape(true)[2:]), K.floatx()) /
K.sum(K.square(pred - true) * mask, axis=[1, 2, 3, 4])) / K.log(10.)
def gram_matrix(x):
x = K.permute_dimensions(x, (0, 3, 1, 2))
shape = K.shape(x)
feat = K.reshape(x, (shape[0], shape[1], shape[2] * shape[3]))
num = K.batch_dot(feat, K.permute_dimensions(feat, (0, 2, 1)))
den = K.prod(K.cast(shape[1:], K.floatx()))
return num / den
def pixelwise_crossentropy_loss_mc(y_true, y_hat):
y_hat += 1e-8 # avoid issues with log
w = K.sum(K.sum(K.sum(y_true, axis=0), axis=2), axis=3) / K.prod(
K.shape(y_true)) / K.shape(y_true)[1]
ce = -(1 - w) * y_true * K.log(y_hat) - w * (1. - y_true) * K.log(1 -
y_hat)
return K.mean(ce)
def construct_loss(model, layer_contributions):
layer_dict = dict([layer.name, layer] for layer in model.layers)
loss = K.variable(0.0)
for layer_name in layer_contributions:
coeff = layer_contributions[layer_name]
activation = layer_dict[layer_name]
# mean of sum of squares (L2norm) of activations scaled by contribution constitutes the loss.
# avoiding border artifacts
scaling = K.prod(K.cast(K.shape(activation), 'float32'))
loss += coeff * K.sum(K.square(activation[:, 2:-2, 2:-2, :])) / scaling
dream = model.input
# The call to `gradients` returns a list of tensors (of size 1 in this case)
# hence we only keep the first element -- which is a tensor.
grads = K.gradients(loss, dream)[0]
# Normalized gradients. We floor with 1e-7 before dividing so as to avoid accidentally dividing by 0.
# grads /= (K.sqrt(K.mean(K.square(grads))) + EPSILON)
grads /= K.maximum(K.mean(L.abs(grads)), EPSILON)
# going from input image to loss and gradients
iterate = K.function([dream], [loss, grads])
return iterate
def training_phase():
mean_batch = K.mean(mean_instance, axis=0, keepdims=True)
variance_batch = K.mean(temp, axis=0,
keepdims=True) - K.square(mean_batch)
mean_batch_reshaped = K.flatten(mean_batch)
variance_batch_reshaped = K.flatten(variance_batch)
if K.backend() != 'cntk':
sample_size = K.prod(
[K.shape(inputs)[axis] for axis in reduction_axes])
sample_size = K.cast(sample_size, dtype=K.dtype(inputs))
# sample variance - unbiased estimator of population variance
variance_batch_reshaped *= sample_size / (sample_size -
(1.0 + self.epsilon))
self.add_update([
K.moving_average_update(self.moving_mean, mean_batch_reshaped,
self.momentum),
K.moving_average_update(self.moving_variance,
variance_batch_reshaped, self.momentum)
], inputs)
return normalize_func(mean_batch, variance_batch)
def get_output(self, train=False):
def format_shape(shape):
if K._BACKEND == 'tensorflow':
def trf(x):
try:
return int(x)
except TypeError:
return x
return map(trf, shape)
return shape
X = self.get_input(train)
in_shape = format_shape(K.shape(X))
batch_flatten_len = K.prod(in_shape[:2])
cast_in_shape = (batch_flatten_len, ) + tuple(in_shape[i] for i in range(2, K.ndim(X)))
pre_outs = self.layer(K.reshape(X, cast_in_shape))
out_shape = format_shape(K.shape(pre_outs))
cast_out_shape = (in_shape[0], in_shape[1]) + tuple(out_shape[i] for i in range(1, K.ndim(pre_outs)))
outputs = K.reshape(pre_outs, cast_out_shape)
return outputs
def exponent_neg_cosine_similarity(x):
""" Helper function for the similarity estimate of the LSTMs outputs """
leftNorm = K.l2_normalize(x[:, :hidden_size], axis=-1)
rightNorm = K.l2_normalize(x[:, hidden_size:], axis=-1)
return K.sum(K.prod([leftNorm, rightNorm], axis=0),
axis=1,
keepdims=True)
def my_acc(target, output):
target = K.cast(target, tf.int32)
correct_count = K.sum(K.cast(K.equal(K.cast(K.argmax(target, axis=-1), tf.int32),
K.cast(K.argmax(output, axis=-1), tf.int32)), tf.int32))
neutral_count = K.sum(K.cast(K.equal(target[:, :, :, -1], K.variable(1, dtype=tf.int32)), tf.int32))
total_count = K.prod(K.shape(output)[:-1]) - neutral_count
return tf.cast(correct_count / total_count, tf.float32)
def get_output(self, train=False):
def format_shape(shape):
if K._BACKEND == 'tensorflow':
def trf(x):
try:
return int(x)
except TypeError:
return x
return map(trf, shape)
return shape
X = self.get_input(train)
in_shape = format_shape(K.shape(X))
batch_flatten_len = K.prod(in_shape[:2])
cast_in_shape = (batch_flatten_len, ) + tuple(
in_shape[i] for i in range(2, K.ndim(X)))
pre_outs = self.layer(K.reshape(X, cast_in_shape))
out_shape = format_shape(K.shape(pre_outs))
cast_out_shape = (in_shape[0], in_shape[1]) + tuple(
out_shape[i] for i in range(1, K.ndim(pre_outs)))
outputs = K.reshape(pre_outs, cast_out_shape)
return outputs
def __call__(self, y_true: plaidml.tile.Value,
y_pred: plaidml.tile.Value) -> plaidml.tile.Value:
""" Calculate the Laplacian Pyramid Loss.
Parameters
----------
y_true: :class:`plaidml.tile.Value`
The ground truth value
y_pred: :class:`plaidml.tile.Value`
The predicted value
Returns
-------
:class: `plaidml.tile.Value`
The loss value
"""
if not self._shape:
self._shape = K.int_shape(y_pred)
pyramid_true = self._get_laplacian_pyramid(y_true)
pyramid_pred = self._get_laplacian_pyramid(y_pred)
losses = K.stack([
K.sum(K.abs(ppred - ptrue)) /
K.cast(K.prod(K.shape(ptrue)), "float32")
for ptrue, ppred in zip(pyramid_true, pyramid_pred)
])
loss = K.sum(losses * self._weights)
return loss
def loss_func(y_true, y_pred):
y_shape = K.shape(y_true)
y_true_mask = tf.where(y_true > -1,
x=tf.ones_like(y_true),
y=tf.zeros_like(y_true))
centers = center_of_mass(y_true_mask)[:, :2]
y_true_sm = tf.image.extract_glimpse(y_true,
crop_size,
offsets=centers,
normalized=False,
centered=False)
y_pred_sm = tf.image.extract_glimpse(y_pred,
crop_size,
offsets=centers,
normalized=False,
centered=False)
scale_difference = K.prod(y_shape[1:]) / (win * win)
error = sse(y_true, y_pred) / tf.cast(scale_difference,
dtype=tf.float32)
error += sse(y_true_sm, y_pred_sm) * factor
return error / (factor + 1)
def sparsity_level(x):
_shape = K.get_variable_shape(x)
shape = K.shape(x)
total = K.cast(K.prod(shape[1:]), K.floatx())
return K.reshape(
K.sum(K.cast(x > 0.0, K.floatx()), axis=range(1, len(_shape))),
(-1, 1)) / total
def gram_matrix(x):
x = K.permute_dimensions(x, (0, 3, 1, 2))
s = K.shape(x)
feat = K.reshape(x, (s[0], s[1], s[2] * s[3]))
feat_T = K.permute_dimensions(feat, (0, 2, 1))
norm_factor = K.prod(K.cast(s[1:], K.floatx()))
return K.batch_flatten(K.batch_dot(feat, feat_T) / norm_factor)
def dream_fxn(model, target_layer_dict):
K.set_learning_phase(0)
# Build the InceptionV3 network with our placeholder.
# The model will be loaded with pre-trained ImageNet weights.
dream = model.input
print('Model loaded.')
# Get the symbolic outputs of each "key" layer (we gave them unique names).
layer_dict = dict([(layer.name, layer) for layer in model.layers])
# Define the loss.
loss = K.variable(0.)
for layer_name in target_layer_dict:
# Add the L2 norm of the features of a layer to the loss.
assert layer_name in layer_dict.keys(), 'Layer ' + layer_name + ' not found in model.'
coeff = target_layer_dict[layer_name]
x = layer_dict[layer_name].output
# We avoid border artifacts by only involving non-border pixels in the loss.
scaling = K.prod(K.cast(K.shape(x), 'float32'))
if K.image_data_format() == 'channels_first':
loss += coeff * K.sum(K.square(x[:, :, 2: -2, 2: -2])) / scaling
else:
loss += coeff * K.sum(K.square(x[:, 2: -2, 2: -2, :])) / scaling
# Compute the gradients of the dream wrt the loss.
grads = K.gradients(loss, dream)[0]
# Normalize gradients.
grads /= K.maximum(K.mean(K.abs(grads)), 1e-7)
# Set up function to retrieve the value
# of the loss and gradients given an input image.
outputs = [loss, grads]
return K.function([dream], outputs)
def __call__(self, loss):
output = self.layer.get_output(True)
batch_size = K.shape(output)[0] // 2
generated = output[:batch_size, :, :, :]
loss += self.weight * K.mean(
K.sum(K.square(gram_matrix(self.target) - gram_matrix(generated)), axis=(1,2))
) / (4.0 * K.square(K.prod(K.shape(generated)[1:])))
return loss
def call(self, x, mask=None):
N_DECISION = (2 ** (self.n_depth)) - 1 # Number of decision nodes
N_LEAF = 2 ** (self.n_depth + 1) # Number of leaf nodes
flat_decision_p_e = []
leaf_p_e = []
for w_d, w_l in zip(self.w_d_ensemble, self.w_l_ensemble):
decision_p = K.sigmoid((K.dot(x, w_d)))
leaf_p = K.softmax(w_l)
decision_p_comp = 1 - decision_p
decision_p_pack = K.concatenate([decision_p, decision_p_comp])
flat_decision_p_e.append(decision_p_pack)
leaf_p_e.append(leaf_p)
#Construct tiling pattern for decision probability matrix
#Could be done in TF, but I think it's better statically
tiling_pattern = np.zeros((N_LEAF, self.n_depth), dtype=np.int32)
comp_offset = N_DECISION
dec_idx = 0
for n in xrange(self.n_depth):
j = 0
for depth_idx in xrange(2**n):
repeat_times = 2 ** (self.n_depth - n)
for _ in xrange(repeat_times):
tiling_pattern[j][n] = dec_idx
j = j + 1
for _ in xrange(repeat_times):
tiling_pattern[j][n] = comp_offset + dec_idx
j = j + 1
dec_idx = dec_idx + 1
flat_pattern = tiling_pattern.flatten()
# iterate over each tree
tree_ret = None
for flat_decision_p, leaf_p in zip(flat_decision_p_e, leaf_p_e):
flat_mu = tf.transpose(tf.gather(tf.transpose(flat_decision_p), flat_pattern))
batch_size = tf.shape(flat_decision_p)[0]
shape = tf.pack([batch_size, N_LEAF, self.n_depth])
mu = K.reshape(flat_mu, shape)
leaf_prob = K.prod(mu, [2])
prob_label = K.dot(leaf_prob, leaf_p)
if tree_ret is None:
tree_ret = prob_label
else:
tree_ret = tree_ret + prob_label
return tree_ret/self.n_trees
def get_output(self, train=False):
X = self.get_input(train)
if self.mode == 'ave':
s = K.mean(X, axis=self.dims)
return s
if self.mode == 'sum':
s = K.sum(X, axis=self.dims)
return s
elif self.mode == 'mul':
s = K.prod(X, axis=self.dims)
return s
else:
raise Exception('Unknown merge mode')
def loss(y_true, y_pred):
from plasma.conf import conf
fac = MaxHingeTarget.fac
#overall_fac = np.prod(np.array(K.shape(y_pred)[1:]).astype(np.float32))
overall_fac = K.prod(K.cast(K.shape(y_pred)[1:],K.floatx()))
max_val = K.max(y_pred,axis=-2) #temporal axis!
max_val1 = K.repeat(max_val,K.shape(y_pred)[-2])
mask = K.cast(K.equal(max_val1,y_pred),K.floatx())
y_pred1 = mask * y_pred + (1-mask) * y_true
weight_mask = K.mean(y_true,axis=-1)
weight_mask = K.cast(K.greater(weight_mask,0.0),K.floatx()) #positive label!
weight_mask = fac*weight_mask + (1 - weight_mask)
#return weight_mask*squared_hinge(y_true,y_pred1)
return conf['model']['loss_scale_factor']*overall_fac*weight_mask*hinge(y_true,y_pred1)
def get_single_deconv_out(input, filter):
# reshape inputs
img = input.reshape((1, 1, input.shape[0], input.shape[1]))
kernel = filter.reshape((1, K.prod(filter.shape)))
# construct split function
# image = T.tensor4("image")
neibs = images2neibs(img, neib_shape=filter.shape, neib_step=filter.shape)
# window_function = theano.function([image], neibs)
#
# neibs_val = window_function(img_val)
neibs = neibs*kernel
# construct merge function
img_new = neibs2images(neibs, filter.shape, img.shape)
return img_new[0][0]
'mixed4': 2.,
'mixed5': 1.5,
}
# 定义需要最大化的损失
# Get the symbolic outputs of each "key" layer (we gave them unique names).
layer_dict = dict([(layer.name, layer) for layer in model.layers])
# Define the loss.
loss = K.variable(0.)
for layer_name in layer_contributions:
# Add the L2 norm of the features of a layer to the loss.
coeff = layer_contributions[layer_name]
activation = layer_dict[layer_name].output # 获取层的输出
# We avoid border artifacts by only involving non-border pixels in the loss.
scaling = K.prod(K.cast(K.shape(activation), 'float32'))
loss += coeff * K.sum(K.square(activation[:, 2: -2, 2: -2, :])) / scaling
# 梯度上升过程
# This holds our generated image
dream = model.input
# Compute the gradients of the dream with regard to the loss.
grads = K.gradients(loss, dream)[0]
# Normalize gradients.
grads /= K.maximum(K.mean(K.abs(grads)), 1e-7)
# Set up function to retrieve the value
# of the loss and gradients given an input image.
outputs = [loss, grads]
dream = model.input
print('Model loaded.')
# Get the symbolic outputs of each "key" layer (we gave them unique names).
layer_dict = dict([(layer.name, layer) for layer in model.layers])
# Define the loss.
loss = K.variable(0.)
for layer_name in settings['features']:
# Add the L2 norm of the features of a layer to the loss.
assert (layer_name in layer_dict.keys(),
'Layer ' + layer_name + ' not found in model.')
coeff = settings['features'][layer_name]
x = layer_dict[layer_name].output
# We avoid border artifacts by only involving non-border pixels in the loss.
scaling = K.prod(K.cast(K.shape(x), 'float32'))
if K.image_data_format() == 'channels_first':
loss += coeff * K.sum(K.square(x[:, :, 2: -2, 2: -2])) / scaling
else:
loss += coeff * K.sum(K.square(x[:, 2: -2, 2: -2, :])) / scaling
# Compute the gradients of the dream wrt the loss.
grads = K.gradients(loss, dream)[0]
# Normalize gradients.
grads /= K.maximum(K.mean(K.abs(grads)), K.epsilon())
# Set up function to retrieve the value
# of the loss and gradients given an input image.
outputs = [loss, grads]
fetch_loss_and_grads = K.function([dream], outputs)