def compute_py(self, x):
'''
compute probability for each class
INPUTS:
x - input
OUTPUTS:
py - histogram of probabilities for each class
'''
hidden1_pre = tfm.add(tfl.matmul(x, self.weights['W_x_to_h1']),
self.weights['b_x_to_h1'])
hidden_post = self.nonlinearity(hidden1_pre)
num_layers_middle = np.shape(self.N_h)[0] - 1
for i in range(num_layers_middle):
ni = i + 2
hidden_pre = tfm.add(
tfl.matmul(hidden_post,
self.weights['W_h{}_to_h{}'.format(ni - 1, ni)]),
self.weights['b_h{}_to_h{}'.format(ni - 1, ni)])
hidden_post = self.nonlinearity(hidden_pre)
p_un = tfm.add(
tfl.matmul(hidden_post, self.weights['W_h{}_to_py'.format(ni)]),
self.weights['b_h{}_to_py'.format(ni)])
p_un = tf.nn.sigmoid(p_un) + 1e-6
py = tfm.divide(
p_un,
tf.tile(tf.expand_dims(tfm.reduce_sum(p_un, axis=1), axis=1),
[1, self.n_y]))
return py
def conv_block(self,
input_layer,
n_filters,
length=2,
pool=True,
stride=1):
layer = input_layer
for i in range(length):
layer = Conv2D(n_filters, (3, 3), strides=stride,
padding='same')(layer)
layer = BatchNormalization()(layer)
layer = ReLU()(layer)
parallel = Conv2D(n_filters, (1, 1),
strides=stride**length,
padding='same')(input_layer)
parallel = BatchNormalization()(parallel)
parallel = ReLU()(parallel)
output = Add()([layer, parallel])
#output = BatchNormalization()(output)
# output=Multiply()([output,K.variable(0.5,shape=K.shape(output),dtype='float64',name='const')])
# output=Multiply()([output,K.ones(shape=K.shape(output))])
output = Lambda(lambda x: divide(x, 2.0))(output)
if pool:
output = MaxPooling2D(pool_size=(3, 3), strides=2)(output)
return output
def augmentation(img, msk):
# Call in skimage package, which will be used for transformations.
import tensorflow.math as Math
# Create some random floats, which will be used in augmentation steps.
tilt = tf.random.uniform(shape=[], minval=-30, maxval=30, dtype=tf.float32)
dx = tf.random.uniform(shape=[], minval=-5, maxval=5, dtype=tf.float32)
dy = tf.random.uniform(shape=[], minval=-5, maxval=5, dtype=tf.float32)
# Use TensforFlow-style if conditionals, used to flip image and mask.
img = tf.cond(tilt > 0, lambda: tf.image.flip_left_right(img),
lambda: tf.image.flip_up_down(img))
msk = tf.cond(tilt > 0, lambda: tf.image.flip_left_right(msk),
lambda: tf.image.flip_up_down(msk))
# Rotate the image and mask to some degree.
# img = rotate(img, angle = tilt, mode = 'reflect')
# msk = rotate(msk, angle = tilt, mode = 'reflect')
toRads = Math.multiply(Math.divide(tilt, 180), tf.constant(math.pi))
img = tfa.image.rotate(img, toRads)
msk = tfa.image.rotate(msk, toRads)
# Affine transformation
img = tfa.image.translate(img, [dx, dy], 'BILINEAR')
msk = tfa.image.translate(msk, [dx, dy], 'BILINEAR')
# Convert the inputs back into tensors, put back into a tuple.
finalTuple = (img, msk)
return finalTuple
def call(self, inputs):
mean = reduce_mean(inputs, axis=0)
std = reduce_std(inputs, axis=0) + 1e-6
InputBatchNormalization.temp += 1
InputBatchNormalization.mean += mean
InputBatchNormalization.std += std
inputs = divide(subtract(inputs, mean), std)
return inputs.squeeze(0)
def compute_py(self, xl):
'''
compute moments of output Gaussian distribution
INPUTS:
x - input
OUTPUTS:
mu_y - mean of output Gaussian distribution
log_sig_sq_y - log variance of output Gaussian distribution
'''
x, _ = NN_utils.reshape_and_extract(xl, self.sz_im)
hidden_post = layers.tf_conv_layer(x, self.weights['W_x_to_h1'],
self.weights['b_x_to_h1'],
self.St[0], self.nonlinearity)
# print(tf.shape(hidden_post).numpy())
num_layers_1 = np.shape(self.N_h1)[0] - 1
for i in range(num_layers_1):
ni = i + 2
hidden_post = layers.tf_conv_layer(
hidden_post, self.weights['W_h{}_to_h{}'.format(ni - 1, ni)],
self.weights['b_h{}_to_h{}'.format(ni - 1, ni)],
self.St[ni - 1], self.nonlinearity)
# print(tf.shape(hidden_post).numpy())
hidden_post = NN_utils.flatten(hidden_post)
# print(tf.shape(hidden_post).numpy())
num_layers_F = np.shape(self.NF_h)[0]
for i in range(num_layers_F):
ni = ni + 1
hidden_pre = tfm.add(
tfl.matmul(hidden_post,
self.weights['W_h{}_to_h{}'.format(ni - 1, ni)]),
self.weights['b_h{}_to_h{}'.format(ni - 1, ni)])
hidden_post = self.nonlinearity(hidden_pre)
# print(tf.shape(hidden_post).numpy())
p_un = tfm.add(
tfl.matmul(hidden_post, self.weights['W_h{}_to_py'.format(ni)]),
self.weights['b_h{}_to_py'.format(ni)])
p_un = tf.nn.sigmoid(p_un) + 1e-6
py = tfm.divide(
p_un,
tf.tile(tf.expand_dims(tfm.reduce_sum(p_un, axis=1), axis=1),
[1, self.n_y]))
return py
def tf_ssim3(x, y, is_normalized=True):
[x1, x2, x3] = tf.split(x, 3, axis=2)
[y1, y2, y3] = tf.split(y, 3, axis=2)
s1 = tf_ssim(x1, y1, is_normalized)
s2 = tf_ssim(x2, y2, is_normalized)
s3 = tf_ssim(x3, y3, is_normalized)
three = tf.constant(3.0)
result = divide(multiOperation(add, s1, s2, s3), three)
return result
def PST(I, LPF, Phase_strength, Warp_strength, Threshold_min, Threshold_max):
#inverting Threshold_min to simplyfy optimization porcess, so we can clip all variable between 0 and 1
LPF = ops.convert_to_tensor_v2(LPF)
Phase_strength = ops.convert_to_tensor_v2(Phase_strength)
Warp_strength = ops.convert_to_tensor_v2(Warp_strength)
I = ops.convert_to_tensor_v2(I)
Threshold_min = ops.convert_to_tensor_v2(Threshold_min)
Threshold_max = ops.convert_to_tensor_v2(Threshold_max)
Threshold_min = -Threshold_min
L = 0.5
x = tf.linspace(-L, L, I.shape[0])
y = tf.linspace(-L, L, I.shape[1])
[X1, Y1] = (tf.meshgrid(x, y))
X = tf.transpose(X1)
Y = tf.transpose(Y1)
[THETA, RHO] = cart2pol(X, Y)
# Apply localization kernel to the original image to reduce noise
Image_orig_f = sig.fft2d(tf.dtypes.cast(I, tf.complex64))
tmp6 = (LPF**2.0) / tfm.log(2.0)
tmp5 = tfm.sqrt(tmp6)
tmp4 = (tfm.divide(RHO, tmp5))
tmp3 = -tfm.pow(tmp4, 2)
tmp2 = tfm.exp(tmp3)
expo = fftshift(tmp2)
Image_orig_filtered = tfm.real(
sig.ifft2d((tfm.multiply(tf.dtypes.cast(Image_orig_f, tf.complex64),
tf.dtypes.cast(expo, tf.complex64)))))
# Constructing the PST Kernel
tp1 = tfm.multiply(RHO, Warp_strength)
PST_Kernel_1 = tfm.multiply(
tp1, tfm.atan(tfm.multiply(RHO, Warp_strength))
) - 0.5 * tfm.log(1.0 + tfm.pow(tf.multiply(RHO, Warp_strength), 2.0))
PST_Kernel = PST_Kernel_1 / tfm.reduce_max(PST_Kernel_1) * Phase_strength
# Apply the PST Kernel
temp = tfm.multiply(
fftshift(
tfm.exp(
tfm.multiply(tf.dtypes.complex(0.0, -1.0),
tf.dtypes.cast(PST_Kernel,
tf.dtypes.complex64)))),
sig.fft2d(tf.dtypes.cast(Image_orig_filtered, tf.dtypes.complex64)))
Image_orig_filtered_PST = sig.ifft2d(temp)
# Calculate phase of the transformed image
PHI_features = tfm.angle(Image_orig_filtered_PST)
out = PHI_features
out = (out / tfm.reduce_max(out)) * 3
return out
def compute_angle_tensor(pts1, pts2):
""" Compute the angle between pt1 and pt2 with respect to the origin
Input:
pts1: batch_size x 1 x 3 tensor
pts2: batch_size x 1 x 3 tensor
"""
b = tf.constant([0.,0.,0.])
angle_diff = []
for pt1, pt2 in zip(pts1, pts2):
ba = tf.subtract(pt1, b)
bc = tf.subtract(pt2, b)
cosine_angle = tm.divide(tf.tensordot(ba, bc, 1), tm.multiply(tf.norm(ba), tf.norm(bc)))
angle = tm.acos(cosine_angle)
angle_diff.append(tf.cast(angle, tf.float32))
return tf.stack(angle_diff, axis=0)
def gaussian_log_likelihood(x, mu_x, log_sig_sq_x, SMALL_CONSTANT=1e-5):
'''
Element-wise Gaussian log likelihood
INPUTS:
x = points
mu_x - means of Gaussians
log_sig_sq_x - log variance of Gaussian
OPTIONAL INPUTS:
SMALL_CONSTANT - small constant to avoid taking the log of 0 or dividing by 0
OUTPUTS:
log_lik - element-wise log likelihood
'''
# -E_q(z|x) log(p(x|z))
normalising_factor = -0.5 * tfm.log(
SMALL_CONSTANT + tfm.exp(log_sig_sq_x)) - 0.5 * np.log(2.0 * np.pi)
square_diff_between_mu_and_x = tfm.square(mu_x - x)
inside_exp = -0.5 * tfm.divide(square_diff_between_mu_and_x,
SMALL_CONSTANT + tfm.exp(log_sig_sq_x))
log_lik = normalising_factor + inside_exp
return log_lik
def call(self, x):
X = []
for i in range(self.n_activations):
self.i = i
frame = x[:, :, i:i + 1]
sigma1 = K.variable(
np.zeros((self.batch, frame.shape[1], frame.shape[2])))
for j in range(self.v_order):
j_fact = math.factorial(j)
p = tfm.divide(K.pow(frame, j), j_fact)
sigma1 = tfm.add(sigma1, tfm.multiply(self.v[i][j], p))
sigma2 = K.variable(
np.zeros((self.batch, frame.shape[1], frame.shape[2])))
for j in range(1, self.w_order + 1):
self.k = j
sigma2 = tfm.add(sigma2, K.map_fn(self.basis2, frame))
X.append(tfm.add(sigma1, sigma2))
output = K.concatenate(X, axis=2)
return output
def log(x, base=None):
if base is None:
return tf.math.log(x)
else:
return divide(tf.math.log(x), tf.math.log(base))
def f2():
val1 = tfm.divide(
tfm.multiply(tfm.subtract(k, k_1), tfm.subtract(k, k_1)), 2)
val2 = tfm.multiply(tfm.subtract(k, k_1), tfm.subtract(x, k))
val = tfm.add(val1, val2)
return val
def f1():
return tfm.add(
tfm.subtract(tfm.divide(tfm.multiply(x, x), 2),
tfm.multiply(k_1, x)),
tfm.divide(tfm.multiply(k_1, k_1), 2))
def DSSIM(y_true, y_pred):
return tfmath.divide(
tfmath.subtract(1.0, tfimage.ssim(y_true, y_pred, max_val=1.0)), 2.0)
def tf_ssim(x, y, is_normalized=False):
"""
k1 = 0.01
k2 = 0.03
L = 1.0 if is_normalized else 255.0
c1 = np.power(k1 * L, 2)
c2 = np.power(k2 * L, 2)
c3 = c2 / 2
"""
k1 = 0.01
k2 = 0.03
L = 1.0 if is_normalized else 255.0
c1 = tf_pow(multiply(k1, L), 2.0)
c2 = tf_pow(multiply(k2, L), 2.0)
c3 = divide(c2, 2.0)
# if type(x) is np.ndarray:
# x = tf.convert_to_tensor(x, dtype=tf.float32)
# if type(y) is np.ndarray:
# y = tf.convert_to_tensor(y, dtype=tf.float32)
"""
ux = x.mean()
uy = y.mean()
"""
ux = tf_mean(x)
uy = tf_mean(y)
"""
std_x = x.std()
std_y = y.std()
"""
std_x = tf_std(x)
std_y = tf_std(y)
"""
xy = (x - ux) * (y - uy)
std_xy = xy.mean()
"""
xy = multiply(subtract(x, ux), subtract(y, uy))
std_xy = tf_mean(xy)
"""
l_xy = (2 * ux * uy + c1) / (np.power(ux, 2) + np.power(uy, 2) + c1)
"""
l_son = add(multiOperation(multiply, 2.0, ux, uy), c1)
l_mom = multiOperation(add, tf_pow(ux, 2.0), tf_pow(uy, 2.0), c1)
l_xy = divide(l_son, l_mom)
"""
c_xy = (2 * std_x * std_y + c2) / (np.power(std_x, 2) + np.power(std_y, 2) + c2)
"""
c_son = add(multiOperation(multiply, 2.0, std_x, std_y), c2)
c_mom = multiOperation(add, tf_pow(std_x, 2.0), tf_pow(std_y, 2.0), c2)
c_xy = divide(c_son, c_mom)
"""
s_xy = (std_xy + c3) / (std_x * std_y + c3)
"""
s_son = add(std_xy, c3)
s_mom = add(multiply(std_x, std_y), c3)
s_xy = divide(s_son, s_mom)
one = tf.constant(1.0)
_ssim = multiOperation(multiply, l_xy, c_xy, s_xy)
_result = tf.cond(greater(_ssim, one), lambda: one, lambda: _ssim)
return _result