示例#1
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def eigen_loss(y_true, y_pred):
    y_true = tf.Print(y_true, [y_true], message='y_true', summarize=30)
    y_pred = tf.Print(y_pred, [y_pred], message='y_pred', summarize=30)

    y_true_clipped = K.clip(y_true, K.epsilon(), None)
    y_pred_clipped = K.clip(y_pred, K.epsilon(), None)

    first_log = K.log(y_pred_clipped + 1.)
    second_log = K.log(y_true_clipped + 1.)
    w_x = K.variable(np.array([[-1., 0., 1.],
                                [-1., 0., 1.],
                                [-1., 0., 1.]]).reshape(3, 3, 1, 1))

    grad_x_pred = K.conv2d(first_log, w_x, padding='same')
    grad_x_true = K.conv2d(second_log, w_x, padding='same')

    w_y = K.variable(np.array([[-1., -1., -1.],
                                [0., 0., 0.],
                                [1., 1., 1.]]).reshape(3, 3, 1, 1))

    grad_y_pred = K.conv2d(first_log, w_y, padding='same')
    grad_y_true = K.conv2d(second_log, w_y, padding='same')
    diff_x = grad_x_pred - grad_x_true
    diff_y = grad_y_pred - grad_y_true

    log_term = K.mean(K.square((first_log - second_log)), axis=-1)
    sc_inv_term = K.square(K.mean((first_log - second_log),axis=-1))
    grad_loss = K.mean(K.square(diff_x) + K.square(diff_y), axis=-1)

    return log_term - (0.5 * sc_inv_term) + grad_loss
def create_vae(batch_size, base_filters=64, latent=8,
               image_size=64, learning_rate=0.001,
               reconstruction_weight=1000, layers=4):
    '''
    Constructs VAE model with given parameters.
    :param batch_size: size of a batch (used for placeholder)
    :param base_filters: number of filters after first layer. Other layers will double this number
    :param latent: latent space dimension
    :param image_size: size of input image
    Returns compiled Keras model along with encoder and decoder
    '''
    if isinstance(image_size, int):
        image_size = (image_size, image_size)
    x = Input(batch_shape=(batch_size, image_size[0], image_size[1], 3))
    encoder = create_encoder([image_size[0], image_size[1], 3], base_filters=base_filters, latent=latent, layers=layers)
    decoder = create_decoder([image_size[0], image_size[1], 3], base_filters=base_filters, latent=latent, layers=layers)
    mean_log_var = encoder(x)
    mean_size = mean_log_var.shape[1]//2
    mean = Lambda(lambda h: h[:, :mean_size])(mean_log_var)
    log_var = Lambda(lambda h: h[:, mean_size:])(mean_log_var)
    z = Lambda(sample)([mean, log_var])
    reconstruction = decoder(z)
    loss_reconstruction = K.mean(metrics.mean_squared_error(x, reconstruction))
    loss_KL = - K.mean(0.5 * K.sum(1 + log_var - K.square(mean) - K.exp(log_var), axis=1))
    loss = reconstruction_weight*loss_reconstruction + loss_KL

    vae = Model(x, reconstruction)
    vae.compile(optimizer=keras.optimizers.Adam(lr=learning_rate), loss=lambda x, y: loss)
    return vae, encoder, decoder
示例#3
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    def call(self, x, mask=None):
        input_shape = self.input_spec[0].shape

        reduction_axes = list(range(len(input_shape)))
        del reduction_axes[self.axis]
        broadcast_shape = [1] * len(input_shape)
        broadcast_shape[self.axis] = input_shape[self.axis]

        # case: train mode (uses stats of the current batch)
        mean = K.mean(x, axis=reduction_axes)
        brodcast_mean = K.reshape(mean, broadcast_shape)
        std = K.mean(K.square(x - brodcast_mean) + self.epsilon, axis=reduction_axes)
        std = K.sqrt(std)
        brodcast_std = K.reshape(std, broadcast_shape)
        mean_update = self.momentum * self.running_mean + (1 - self.momentum) * mean
        std_update = self.momentum * self.running_std + (1 - self.momentum) * std
        self.updates = [(self.running_mean, mean_update),
                        (self.running_std, std_update)]
        x_normed = (x - brodcast_mean) / (brodcast_std + self.epsilon)

        # case: test mode (uses running averages)
        brodcast_running_mean = K.reshape(self.running_mean, broadcast_shape)
        brodcast_running_std = K.reshape(self.running_std, broadcast_shape)
        x_normed_running = ((x - brodcast_running_mean) / (brodcast_running_std + self.epsilon))

        # pick the normalized form of x corresponding to the training phase
        x_normed = K.in_train_phase(x_normed, x_normed_running)
        out = K.reshape(self.gamma, broadcast_shape) * x_normed + K.reshape(self.beta, broadcast_shape)

        return out
示例#4
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def criterion_GAN(output, target, use_lsgan=True):
    if use_lsgan:
        diff = output - target
        dims = list(range(1, K.ndim(diff)))
        return K.expand_dims((K.mean(diff ** 2, dims)), 0)
    else:
        return K.mean(K.log(output + 1e-12) * target + K.log(1 - output + 1e-12) * (1 - target))
示例#5
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    def mutual_info_loss(self, c, c_given_x):
        """The mutual information metric we aim to minimize"""
        eps = 1e-8
        conditional_entropy = K.mean(- K.sum(K.log(c_given_x + eps) * c, axis=1))
        entropy = K.mean(- K.sum(K.log(c + eps) * c, axis=1))

        return conditional_entropy + entropy
示例#6
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 def func(y_true, y_pred):
     Gxx = _get_kernel(y_true, y_true)
     Gzz = _get_kernel(y_pred, y_pred)
     Gxz = _get_kernel(y_true, y_pred)
     cost = K.log(K.sqrt(K.mean(Gxx)*K.mean(Gzz)) /
                  K.mean(Gxz))
     return cost
示例#7
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 def get_loss(self):
     loss = 0.0
     if self.l1:
         loss += K.mean(K.abs(self.p)) * self.l1
     if self.l2:
         loss += K.mean(K.square(self.p)) * self.l2
     return loss
def visualize_mser_classifier():
	model = load_model('mser_classifier')
	# Get the symbolic outputs of each "key" layer
	layer_dict = dict([(layer.name, layer) for layer in model.layers])
	layer_name = 'block5_conv3'
	# Can be any integer from 0 to 511, as there are 512 filters in that layer
	kept_filters = []
	for filter_index in range(200):
		print(filter_index)
		# Loss function that maximizes the activation
		# of the nth filter of the layer considered
		layer_output = layer_dict[layer_name].output
		loss = K.mean(layer_output[:, :, :, filter_index])
		# Placeholder for the input images
		input_img = model.input
		# Dimensions of the generated pictures for each filter.
		img_width = 128
		img_height = 128
		# Compute the gradient of the input picture wrt this loss
		grads = K.gradients(loss, input_img)[0]
		# Normalize the gradient
		grads /= (K.sqrt(K.mean(K.square(grads))) + 1e-5)
		# This function returns the loss and grads given the input picture
		iterate = K.function([input_img], [loss, grads])
		# Step size for gradient ascent
		step = 1
		# Start with a random gray image
		input_img_data = np.random.random((1, img_width, img_height, 3)) * 20 + 128
		# run gradient ascent for 20 steps
		for i in range(20):
		    loss_value, grads_value = iterate([input_img_data])
		    input_img_data += grads_value * step
		    print('Current loss value:', loss_value)
		    if loss_value <= 0.:
		    	# some filters get stuck to 0, we can skip them
		    	break
		# Append generated image
		if loss_value > 0:
			img = deprocess_image(input_img_data[0])
			kept_filters.append((img, loss_value))
	# Stich the best 16 filters on a 4 x 4 grid
	n = 4
	# The filters that have the highest loss are assumed to be better-looking.
	# Keep the best 64 filters.
	kept_filters.sort(key=lambda x: x[1], reverse=True)
	kept_filters = kept_filters[:n * n]
	# Build a black picture with enough space for
	# all 4 x 4 filters of size 128 x 128, with a 5px margin in between
	margin = 5
	width = n * img_width + (n - 1) * margin
	height = n * img_height + (n - 1) * margin
	stitched_filters = np.zeros((width, height, 3))
	# Fill the picture with the saved filters
	for i in range(n):
	    for j in range(n):
	        img, loss = kept_filters[i * n + j]
	        stitched_filters[(img_width + margin) * i: (img_width + margin) * i + img_width,
	                         (img_height + margin) * j: (img_height + margin) * j + img_height, :] = img
	# Save the result to disk
	imsave('mser_classifier_stitched_filters_%dx%d.png' % (n, n), stitched_filters)
示例#9
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    def visualize_layer(self, layer, model, keep_filters, out_path, vis_size):
        layer_output = layer.output
        num_filters = layer.nb_filter
        filters = []
        img_width = vis_size[0]
        img_height = vis_size[1]

        for filter_index in xrange(num_filters):
            loss = K.mean(K.mean(layer_output[:, filter_index, :, :]))

            # compute the gradient of the input picture wrt this loss
            grads = K.gradients(loss, model.layers[0].input)[0]

            # normalization trick: we normalize the gradient
            grads /= (K.sqrt(K.mean(K.square(grads))) + 1e-5)

            # this function returns the loss and grads given the input picture
            iterate = K.function([model.layers[0].input], [loss, grads])

            # step size for gradient ascent
            step = 1.

            input_img_data = np.random.random((1, 1, img_width, img_height)) * 20 + 128.

            for i in xrange(50):
                loss_value, grads_value = iterate([input_img_data])
                input_img_data += grads_value * step

                if loss_value <= 0:
                    break

            img = self.deprocess_image(input_img_data[0])
            filters.append((img, loss_value))

        filters.sort(key=lambda x: x[1], reverse=True)
        filters = filters[:keep_filters]

        # get number of grid rows and columns
        grid_r, grid_c = helpers.get_grid_dim(keep_filters)

        # create figure and axes
        fig, axes = plt.subplots(min([grid_r, grid_c]),
                                 max([grid_r, grid_c]))


        # iterate filters inside every channel
        for l, ax in enumerate(axes.flat):
            # get a single filter
            img = filters[l][0][:, :, 0]
            # put it on the grid
            ax.imshow(img, interpolation='bicubic', cmap='Greys')
            # remove any labels from the axes
            ax.set_xticks([])
            ax.set_yticks([])
        # save figure
        out_path = os.path.join(out_path, layer.name) + '.png'
        plt.savefig(out_path, bbox_inches='tight')

        """
def label_reg_loss(y_true, y_pred):
  # KL-div
  y_true = K.clip(y_true, K.epsilon(), 1)
  y_pred = K.clip(y_pred, K.epsilon(), 1)

  y_true_mean = K.mean(y_true, axis=0)
  y_pred_mean = K.mean(y_pred, axis=0)
  return K.sum(y_true_mean * K.log(y_true_mean / y_pred_mean), axis=-1)
 def nme(self, y_true, y_pred):
     y_pred_reshape = K.reshape(y_pred, (-1, self.config.num_output//2, 2))
     y_true_reshape = K.reshape(y_true, (-1, self.config.num_output//2, 2))
     interocular_distance = K.sqrt(K.sum(
         (K.mean(y_true_reshape[:, 36:42, :], axis=1) - K.mean(y_true_reshape[:, 42:48, :], axis=1)) ** 2, axis=-1))
     return K.mean(K.sum(
         K.sqrt(K.sum((y_pred_reshape - y_true_reshape) ** 2, axis=-1))
         , axis=-1)) / K.mean((interocular_distance * self.config.num_output / 2))
def pearson_loss(y_true_rank, y_pred_rank, eps=1e-10):
    y_true_mean = K.mean(y_true_rank)
    y_pred_mean = K.mean(y_pred_rank)
    u1 = (y_true_rank - y_true_mean)
    u2 = (y_pred_rank - y_pred_mean)
    u=K.sum(tf.multiply(u1,u2))
    d=K.sqrt(K.sum(K.square(u1))*K.sum(K.square(u2)))
    rou=tf.div(u,d+eps)
    return 1.-rou
示例#13
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文件: focal_loss.py 项目: Daiver/jff
	def focal_loss_fixed(y_true, y_pred):
		if(K.backend()=="tensorflow"):
			import tensorflow as tf
			pt = tf.where(tf.equal(y_true, 1), y_pred, 1 - y_pred)
			return -K.mean(alpha * K.pow(1. - pt, gamma) * K.log(pt))
		if(K.backend()=="theano"):
			import theano.tensor as T
			pt = T.where(T.eq(y_true, 1), y_pred, 1 - y_pred)
			return -K.mean(alpha * K.pow(1. - pt, gamma) * K.log(pt))
示例#14
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文件: Trainer.py 项目: Nioy/faceswap
    def setup(self):
        distorted_A, fake_A, fake_sz64_A, mask_A, self.path_A, self.path_mask_A, self.path_abgr_A, self.path_bgr_A = self.cycle_variables(self.model.netGA)
        distorted_B, fake_B, fake_sz64_B, mask_B, self.path_B, self.path_mask_B, self.path_abgr_B, self.path_bgr_B = self.cycle_variables(self.model.netGB)
        real_A = Input(shape=self.model.img_shape)
        real_B = Input(shape=self.model.img_shape)

        if self.use_lsgan:
            self.loss_fn = lambda output, target : K.mean(K.abs(K.square(output-target)))
        else:
            self.loss_fn = lambda output, target : -K.mean(K.log(output+1e-12)*target+K.log(1-output+1e-12)*(1-target))

        # ========== Define Perceptual Loss Model==========
        if self.use_perceptual_loss:
            from keras.models import Model
            from keras_vggface.vggface import VGGFace
            vggface = VGGFace(include_top=False, model='resnet50', input_shape=(224, 224, 3))
            vggface.trainable = False
            out_size55 = vggface.layers[36].output
            out_size28 = vggface.layers[78].output
            out_size7 = vggface.layers[-2].output
            vggface_feat = Model(vggface.input, [out_size55, out_size28, out_size7])
            vggface_feat.trainable = False
        else:
            vggface_feat = None

        loss_DA, loss_GA = self.define_loss(self.model.netDA, real_A, fake_A, fake_sz64_A, distorted_A, vggface_feat)
        loss_DB, loss_GB = self.define_loss(self.model.netDB, real_B, fake_B, fake_sz64_B, distorted_B, vggface_feat)

        if self.use_mask_refinement:
            loss_GA += 1e-3 * K.mean(K.square(mask_A))
            loss_GB += 1e-3 * K.mean(K.square(mask_B))
        else:
            loss_GA += 3e-3 * K.mean(K.abs(mask_A))
            loss_GB += 3e-3 * K.mean(K.abs(mask_B))

        w_fo = 0.01
        loss_GA += w_fo * K.mean(self.first_order(mask_A, axis=1))
        loss_GA += w_fo * K.mean(self.first_order(mask_A, axis=2))
        loss_GB += w_fo * K.mean(self.first_order(mask_B, axis=1))
        loss_GB += w_fo * K.mean(self.first_order(mask_B, axis=2))

        weightsDA = self.model.netDA.trainable_weights
        weightsGA = self.model.netGA.trainable_weights
        weightsDB = self.model.netDB.trainable_weights
        weightsGB = self.model.netGB.trainable_weights

        # Adam(..).get_updates(...)
        training_updates = Adam(lr=self.lrD, beta_1=0.5).get_updates(weightsDA,[],loss_DA)
        self.netDA_train = K.function([distorted_A, real_A],[loss_DA], training_updates)
        training_updates = Adam(lr=self.lrG, beta_1=0.5).get_updates(weightsGA,[], loss_GA)
        self.netGA_train = K.function([distorted_A, real_A], [loss_GA], training_updates)

        training_updates = Adam(lr=self.lrD, beta_1=0.5).get_updates(weightsDB,[],loss_DB)
        self.netDB_train = K.function([distorted_B, real_B],[loss_DB], training_updates)
        training_updates = Adam(lr=self.lrG, beta_1=0.5).get_updates(weightsGB,[], loss_GB)
        self.netGB_train = K.function([distorted_B, real_B], [loss_GB], training_updates)
示例#15
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def calc_loss(pred, target, loss='l2'):
    """ Calculate Loss from Shoanlu GAN """
    if loss.lower() == "l2":
        return K.mean(K.square(pred - target))
    if loss.lower() == "l1":
        return K.mean(K.abs(pred - target))
    if loss.lower() == "cross_entropy":
        return -K.mean(K.log(pred + K.epsilon()) * target +
                       K.log(1 - pred + K.epsilon()) * (1 - target))
    raise ValueError('Recieve an unknown loss type: {}.'.format(loss))
示例#16
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def pearsonobj(y_true, y_pred):
    """ Pearson's r objective for STS grade correlation """
    ny_true = _y2num(y_true)
    ny_pred = _y2num(y_pred)
    my_true = K.mean(ny_true)
    my_pred = K.mean(ny_pred)
    var_true = (ny_true - my_true)**2
    var_pred = (ny_pred - my_pred)**2
    return - K.sum((ny_true - my_true) * (ny_pred - my_pred), axis=-1) / \
             (K.sqrt(K.sum(var_true, axis=-1) * K.sum(var_pred, axis=-1)))
def linear_correlation_loss(y_true, y_pred):
    mean_y_true = K.mean(y_true)
    mean_y_pred = K.mean(y_pred)
    std_y_true = K.std(y_true)+1e-6
    std_y_pred = K.std(y_pred)+1e-6
    nSamples = K.shape(y_true)[0]
    firstTerm = (y_true - mean_y_true)/std_y_true
    secondTerm = (y_pred - mean_y_pred)/std_y_pred
    pearsonCorr = K.sum(firstTerm*secondTerm)/(nSamples-1)
    maeLoss = K.abs(y_true-y_pred)
    return maeLoss*(1-K.maximum(0.,pearsonCorr))
示例#18
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 def vae_loss(self, x, x_decoded_mean_squash, z_mean, z_log_var):
     x = K.flatten(x)
     x_decoded_mean_squash = K.flatten(x_decoded_mean_squash)
     img_rows, img_cols = self._img_rows, self._img_cols
     # generative or reconstruction loss
     xent_loss = img_rows * img_cols * \
         metrics.binary_crossentropy(x, x_decoded_mean_squash)
     # Kullback-Leibler divergence loss
     kl_loss = - 0.5 * K.mean(
         1 + z_log_var - K.square(z_mean) - K.exp(z_log_var), axis=-1)
     return K.mean(xent_loss + kl_loss)
示例#19
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文件: keras.py 项目: mwojnars/nifty
 def call(self, x):
     
     # statistics computed along features dimension, on every spatial position of the input tensor
     A   = K.mean(K.abs(x), axis = self.channel_axis)            # mean absolute value
     M1  = K.mean(x, axis = self.channel_axis)                   # mean value
     M2  = K.mean(x**2, axis = self.channel_axis)                # squared quadratic average
     V   = M2 - M1**2                                            # variance: V[X] = E[X^2] - E[X]^2
     eps = 0.001 #K.epsilon()
     
     norm = K.pow(V + eps, self.norm_dev/2) * K.pow(M2 + eps, self.norm_mag/2) * K.pow(A + eps, self.norm_abs)
     return x / norm[...,None]
示例#20
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 def call(self, x, mask=None):
     if mask is not None:
         mask = K.cast(mask, K.floatx())
         mask = K.expand_dims(mask, axis=-1)
         s = K.sum(mask, axis=1)
         if K.equal(s, K.zeros_like(s)) is None:
             return K.mean(x, axis=1)
         else:
             return K.cast(K.sum(x * mask, axis=1) / (K.sqrt(s) + K.constant(1e-10, dtype=K.floatx())), K.floatx())
     else:
         print (x)
         return K.mean(x, axis=1)
示例#21
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def normals_metric(y_true, y_pred):

    y_true = K.variable(y_true)
    y_pred = K.variable(y_pred)

    y_true = K.expand_dims(y_true,0)


    filter_y = K.variable(np.array([[ 0., -0.5 , 0.],
                               [0., 0., 0.],
                               [0., 0.5, 0.]]).reshape(3, 3, 1, 1))


    filter_x = K.variable(np.array([ [0, 0., 0.],
                               [0.5, 0., -0.5],
                               [0., 0., 0.]]).reshape(3, 3, 1, 1))

    dzdx = K.conv2d(K.exp(y_true), filter_x, padding='same')
    dzdy = K.conv2d(K.exp(y_true), filter_y, padding='same')

    dzdx_ = dzdx * -1.0#K.constant(-1.0, shape=[batch_size,K.int_shape(y_pred)[1],K.int_shape(y_pred)[2],K.int_shape(y_pred)[3]]) #K.constant(-1.0, shape=K.int_shape(dzdx))
    dzdy_ = dzdy * -1.0#K.constant(-1.0, shape=[batch_size,K.int_shape(y_pred)[1],K.int_shape(y_pred)[2],K.int_shape(y_pred)[3]]) #K.constant(-1.0, shape=K.int_shape(dzdy))

    mag_norm = K.pow(dzdx,2) + K.pow(dzdy,2) + 1.0#K.constant(1.0, shape=[batch_size,K.int_shape(y_pred)[1],K.int_shape(y_pred)[2],K.int_shape(y_pred)[3]]) #K.constant(1.0, shape=K.int_shape(dzdx))

    mag_norm = K.sqrt(mag_norm)
    N3 = 1.0 / mag_norm #K.constant(1.0, shape=K.int_shape(dzdx)) / mag_norm
    N1 = dzdx_ / mag_norm
    N2 = dzdy_ / mag_norm

    normals = K.concatenate(tensors=[N1,N2,N3],axis=-1)

    dzdx_pred = K.conv2d(K.exp(y_pred), filter_x, padding='same')
    dzdy_pred = K.conv2d(K.exp(y_pred), filter_y, padding='same')

    mag_norm_pred = K.pow(dzdx_pred,2) + K.pow(dzdy_pred,2) + 1.0
    mag_norm_pred = K.sqrt(mag_norm_pred)

    grad_x = K.concatenate(tensors=[1.0/ mag_norm_pred,
                                    0.0/ mag_norm_pred, dzdx_pred/ mag_norm_pred],axis=-1)
    grad_y = K.concatenate(tensors=[0.0/ mag_norm_pred,
                                    1.0/ mag_norm_pred, dzdy_pred/ mag_norm_pred],axis=-1)


    dot_term_x = K.mean(K.sum(normals[0,:,:,:] * grad_x[0,:,:,:], axis=-1, keepdims=True), axis=-1)
    dot_term_y = K.mean(K.sum(normals[0,:,:,:] * grad_y[0,:,:,:], axis=-1, keepdims=True), axis=-1)


    dot_term_x = K.abs(dot_term_x)
    dot_term_y = K.abs(dot_term_y)

    return K.eval(K.mean(dot_term_x)),K.eval(K.mean(dot_term_y))
示例#22
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      def weighted(y_true, y_pred, weights, mask=None):
        assert mask is None
        assert weights is not None
        score_array = fn(y_true, y_pred)

        # reduce score_array to same ndim as weight array
        ndim = K.ndim(score_array)
        weight_ndim = K.ndim(weights)
        score_array = K.mean(score_array, axis=list(range(weight_ndim, ndim)))

        # apply sample weighting
        score_array *= weights
        word_scores = K.sum(score_array, axis=-1)
        return K.mean(word_scores)
def linear_correlation_loss(y_true, y_pred):
    mean_y_true = K.mean(y_true)
    mean_y_pred = K.mean(y_pred)
    std_y_true = K.std(y_true)+1e-6
    std_y_pred = K.std(y_pred)+1e-6
    nSamples = K.shape(y_true)[0]
    firstTerm = (y_true - mean_y_true)/std_y_true
    secondTerm = (y_pred - mean_y_pred)/std_y_pred
    pearsonCorr = K.sum(firstTerm*secondTerm)/(nSamples-1)
    pearsonCorr = K.clip(pearsonCorr,-1.,1.)
    maeLoss = K.mean(K.abs(y_true-y_pred))
    # loss  = 1./(0.1+K.exp(-0.5*K.log(maeLoss+(1-pearsonCorr))))
    loss = (1./(0.1+K.exp(-0.5*K.log(maeLoss))))*(2-pearsonCorr)
    return loss
def generate_pattern(modle, layer_name, filter_index, size=150):
	'''builds a loss func that maximizes the activation of the nth filter of the layer under consideration.'''
	layer_output = model.get_layer(layer_name).output
	loss = K.mean(layer_output[:, :, :, filter_index])
	grads = K.gradients(loss, model.input)[0]
	grads /= (K.sqrt(K.mean(K.square(grads))) + 1e-5)
	iterate = K.function([model.input], [loss, grads])
	input_img_data = np.random.random((1, size, size, 3)) * 20 + 128.
	step = 1
	for i in range(40):
		loss_value, grads_value = iterate([input_img_data])
		input_img_data += grads_value * step
	img = input_img_data[0]
	return deprocess_image(img)
示例#25
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def obj_mix(Y_true,Y_pred):
    """
    Calculates the binary cross entropy on the aggregated outputs of each 
    batch. Use the max when y_true == 1 but the mean when y_true== 0
    """
    y_true = K.mean(Y_true,axis=0)
    if y_true == 1:
        y_pred = K.max(Y_pred,axis=0)
        return(K.mean(K.binary_crossentropy(y_pred, y_true)))
    elif y_true == 0:
        return(K.mean(K.binary_crossentropy(Y_pred,Y_true)))
    else:
        print('unexpected value of y_true',y_true)
        return(K.mean(K.binary_crossentropy(Y_pred,Y_true)))
示例#26
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    def _build(self):
        fake, _, _, g_additional_losses = self.g.run_internal_graph(self.g.inputs)

        real = self.d.inputs[0]
        data = concat([fake, real], axis=0)

        realness, _, _, d_additional_losses = self.d.run_internal_graph(
            [data] + self.d.inputs[1:])

        nb_fakes = fake.shape[0]
        fake_realness = realness[:nb_fakes]
        real_realness = realness[nb_fakes:]
        split = 2*nb_fakes // 3
        g_fake_realness = fake_realness[:split]
        d_fake_realness = fake_realness[split:]

        outputs = OrderedDict()
        g_loss = K.mean(K.binary_crossentropy(g_fake_realness, K.ones_like(real_realness)))
        outputs['g_loss'] = g_loss
        g_reg_loss = sum([v for v in g_additional_losses.values()])
        if g_reg_loss != 0:
            outputs['g_reg_loss'] = g_reg_loss
        g_total_loss = g_loss + g_reg_loss

        d_loss = K.mean(K.binary_crossentropy(real_realness, K.ones_like(real_realness)))
        d_loss += K.mean(K.binary_crossentropy(d_fake_realness, K.zeros_like(real_realness)))
        outputs['d_loss'] = d_loss
        d_reg_loss = sum([v for v in d_additional_losses.values()])
        if d_reg_loss != 0:
            outputs['d_reg_loss'] = d_reg_loss
        d_total_loss = d_loss + d_reg_loss

        inputs = {i.name: i for i in self.g.inputs + self.d.inputs}
        inputs_list = []
        for name in self.input_names:
            inputs_list.append(inputs[name])

        g_updates = self.g_optimizer.get_updates(
            collect_trainable_weights(self.g), self.g.constraints, g_total_loss)
        d_updates = self.d_optimizer.get_updates(
            collect_trainable_weights(self.d), self.d.constraints, d_total_loss)

        if self.uses_learning_phase:
            lr_phase = [K.learning_phase()]
        else:
            lr_phase = []
        self.metrics_names = list(outputs.keys())
        self._train_function = K.function(inputs_list + lr_phase, list(outputs.values()),
                                          updates=g_updates + d_updates)
示例#27
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		def total_loss(y_true, y_pred):
			output_list = []
			temp = []
			num_post = [1]*self.dim_feature
			for i in range(self.dim_feature):
				temp.append(y_pred[:,i*self.dim_feature+i])
			p0 = tf.transpose(tf.stack(temp))
			for j in range(len(yy)):
				temp[yy[j]] += y_pred[:,xx[j]*self.dim_feature+yy[j]]
				num_post[yy[j]] += 1
			for k in range(len(num_post)):
				temp[k] /= num_post[k]
			output_list = temp
			p = tf.transpose(tf.stack(output_list))
			return 100*(K.mean(K.square(K.mean(p, axis = 0)-self.center_prob),axis = -1)-self.alpha*K.mean(K.log(K.abs(p-self.center_prob)+self.relax), axis = -1)+self.beta*K.mean(K.square(p0-p), axis = -1))
示例#28
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def binary_crossentropy_with_ranking(y_true, y_pred):
    """ Trying to combine ranking loss with numeric precision"""
    # first get the log loss like normal
    logloss = K.mean(K.binary_crossentropy(y_pred, y_true), axis=-1)

    # next, build a rank loss

    # clip the probabilities to keep stability
    y_pred_clipped = K.clip(y_pred, K.epsilon(), 1-K.epsilon())

    # translate into the raw scores before the logit
    y_pred_score = K.log(y_pred_clipped / (1 - y_pred_clipped))

    # determine what the maximum score for a zero outcome is
    y_pred_score_zerooutcome_max = K.max(y_pred_score * (y_true <1))

    # determine how much each score is above or below it
    rankloss = y_pred_score - y_pred_score_zerooutcome_max

    # only keep losses for positive outcomes
    rankloss = rankloss * y_true

    # only keep losses where the score is below the max
    rankloss = K.square(K.clip(rankloss, -100, 0))

    # average the loss for just the positive outcomes
    rankloss = K.sum(rankloss, axis=-1) / (K.sum(y_true > 0) + 1)

    # return (rankloss + 1) * logloss - an alternative to try
    return rankloss + logloss
def recall_loss(y_true, y_pred):
    '''
    input: y_true (theano Tensor), y_pred (theano Tensor)
    output: recall_loss (float)
    '''
    # print(K.ndim(y_true), K.ndim(y_pred))
    return -np.log(K.mean(K.equal(K.argmax(y_true, axis=-1), K.argmax(y_pred, axis=-1))))
示例#30
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def kl_loss(truth_dummy, x_mean_log_var_output):
    x_mean, x_log_var = tf.split(x_mean_log_var_output, 2, axis=1)
    print('x_mean shape in kl_loss: ', x_mean.get_shape())
    kl_loss = - 0.5 * \
        K.mean(1 + x_log_var - K.square(x_mean) -
              K.exp(x_log_var), axis=-1)
    return kl_loss
示例#31
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def accuracy(y_true, y_pred):
    return K.mean(K.equal(y_true, K.cast(y_pred < 0.5, y_true.dtype)))
示例#32
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def style_transfer(content_image_path, style_image_path):
    mydir = './Outputs/style_transfer_details'

    # 1: load the content and style images, then rescale the style image to the scale of content image
    content_img = Tools.load_img_and_preprocess_resize(content_image_path, resize=512)
    h, w = content_img.shape[1:3]

    # test_content_reconstruction(content_img[0], mydir, [16, 17, 18, 19], 0)

    style_img = Tools.load_img_and_preprocess_shape(style_image_path, (h, w))
    # show all blocks output
    # test_style_reconstruction(style_img[0], mydir, 1)

    batch_shape = content_img.shape
    shape = content_img.shape[1:]

    vgg = Tools.VGG19_AvgPool(shape)
    print(vgg.summary())

    # 2: get content and style features + features extractor model
    content_features, content_features_extractor_model = ContentReconstruction.get_content_image_features(content_img,
                                                                                                          14, vgg)
    style_layers_features_outputs, symbolic_conv_outputs, style_features_extractor_model = StyleReconstruction.get_style_image_features(
        style_img, 5, vgg)

    # we will assume the weight of the content loss is 1
    # and only weight the style losses
    style_weights = [0.2, 0.4, 0.3, 0.5, 0.2]
    # style_weights = [0.4, 0.6, 0.6, 0.7, 0.4]

    # create the total loss which is the sum of content + style loss
    loss = 1 * K.mean(K.square(content_features_extractor_model.output - content_features))

    for w, symbolic, actual in zip(style_weights, symbolic_conv_outputs, style_layers_features_outputs):
        # gram_matrix() expects a (H, W, C) as input
        loss += w * Tools.style_loss(symbolic[0], actual[0])

    # loss += 0.0001 * tf.image.total_variation(vgg.input)

    # once again, create the gradients and loss + grads function
    # note: it doesn't matter which model's input you use
    # they are both pointing to the same keras Input layer in memory
    grads = K.gradients(loss, vgg.input)

    # just like theano.function
    get_loss_and_grads = K.function(
        inputs=[vgg.input],
        outputs=[loss] + grads
    )

    def get_loss_and_grads_wrapper(x_vec):
        l, g = get_loss_and_grads([x_vec.reshape(*batch_shape)])
        return l.astype(np.float64), g.flatten().astype(np.float64)

    final_image, losses = Tools.LBFGS_Optimizer(get_loss_and_grads_wrapper, 10, batch_shape)

    # plot loss
    plt.plot(losses)
    # plt.savefig(plot_name)
    plt.show()

    # save image
    final_image = Tools.scale_img(final_image)
    plt.imshow(final_image)
    # plt.imsave(file_name, final_image)
    plt.show()
示例#33
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 def loss(chain_start, x):
     x_rec, _, _ = self.mcmc_chain(chain_start, self.nb_gibbs_steps)
     cd = K.mean(self.free_energy(x)) - K.mean(self.free_energy(x_rec))
     return cd, x_rec
示例#34
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 def build_decoder(self, latent, name='conv', n_layers=1):
     decoder = latent
     if name == 'conv':
         if n_layers == 3:
             decoder = Dense(self.window_size // 64 * 256,
                             activation='relu',
                             name='decoder_dense1')(decoder)
             decoder = Reshape((self.window_size // 64, 256),
                               name='decoder_reshape1')(decoder)
             decoder = UpSampling1D(4, name='decoder_upsample1')(decoder)
             decoder = Conv1D(128,
                              3,
                              padding='same',
                              activation='relu',
                              name='decoder_conv1')(decoder)
             decoder = UpSampling1D(4, name='decocer_upsample2')(decoder)
             decoder = Conv1D(64,
                              3,
                              padding='same',
                              activation='relu',
                              name='decoder_conv2')(decoder)
         if n_layers == 2:
             decoder = Dense(self.window_size // 16 * 128,
                             activation='relu',
                             name='decoder_dense1')(decoder)
             decoder = Reshape((self.window_size // 16, 128),
                               name='decoder_reshape1')(decoder)
             decoder = UpSampling1D(4, name='decocer_upsample2')(decoder)
             decoder = Conv1D(64,
                              3,
                              padding='same',
                              activation='relu',
                              name='decoder_conv2')(decoder)
         if n_layers == 1:
             decoder = Dense(self.window_size // 4 * 64,
                             activation='relu',
                             name='decoder_dense1')(decoder)
             decoder = Reshape((self.window_size // 4, 64),
                               name='decoder_reshape1')(decoder)
         decoder = UpSampling1D(4, name='decoder_upsample3')(decoder)
         decoder = Conv1D(4, 1, padding='same',
                          name='decoder_conv3')(decoder)
         decoder = Lambda(lambda x: K.softmax(x, axis=-1),
                          name='output_softmax')(decoder)
         decoder = Lambda(lambda x: K.mean(K.reshape(
             x, (-1, self.n_sampler, self.window_size, self.n_channels)),
                                           axis=1),
                          name='output_mean')(decoder)
     elif name == 'mlp':
         if n_layers >= 2:
             decoder = Dense(128, activation='relu',
                             name='decoder_dense2')(decoder)
         decoder = Dense(self.window_size * self.n_channels,
                         name='decoder_dense3')(decoder)
         decoder = Lambda(lambda x: K.softmax(x, axis=-1),
                          name='output_softmax')(decoder)
         decoder = Lambda(lambda x: K.mean(K.reshape(
             x, (-1, self.n_sampler, self.window_size, self.n_channels)),
                                           axis=1),
                          name='output_mean')(decoder)
     elif name == 'lstm':
         decoder = LSTM(64, name='encoder_lstm1',
                        return_sequences=True)(decoder)
     return decoder
 def mae_tol(y_true,y_pred):
     return K.mean( K.maximum(K.abs(y_true - y_pred) - tol, 0) )
示例#36
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def earth_mover_loss(y_true, y_pred):
    cdf_ytrue = K.cumsum(y_true, axis=-1)
    cdf_ypred = K.cumsum(y_pred, axis=-1)
    samplewise_emd = K.sqrt(
        K.mean(K.square(K.abs(cdf_ytrue - cdf_ypred)), axis=-1))
    return K.mean(samplewise_emd)
示例#37
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x = Dense(intermediate_dim, activation='relu')(latent_inputs)
outputs = Dense(original_dim, activation='sigmoid')(x)
# instantiate decoder model
decoder = Model(latent_inputs, outputs, name='decoder')
# instantiate VAE model
outputs = decoder(encoder(inputs)[2])
vae = Model(inputs, outputs, name='vae_mlp')
models = (encoder, decoder)
data = (x_test, y_test)

reconstruction_loss = mse(inputs, outputs)
reconstruction_loss *= original_dim
kl_loss = 1 + z_log_var - K.square(z_mean) - K.exp(z_log_var)
kl_loss = K.sum(kl_loss, axis=-1)
kl_loss *= -0.5
vae_loss = K.mean(reconstruction_loss + kl_loss)
vae.add_loss(vae_loss)
vae.compile(optimizer='adam')

vae.load_weights("vae_mlp_mnist_D_" + str(latent_dim) + ".h5")

### find the latent encoding (i.e., the mean vector) of the target image
z_mean, _, _ = encoder.predict(x_test[target_img_ind, :, :, 0].reshape(1, -1),
                               batch_size=batch_size)
print("z_mean: ", z_mean.shape)

dim_high = 28

# eps defines the search space for the perturbations with bounded inf norm
eps = 0.2
target_class_ind = 0  # The target class if targeted-attack is used; it is not used in the current versionn, but can be easily adapted
def cosine_distance(left, right):
    left = K.l2_normalize(left, axis=-1)
    right = K.l2_normalize(right, axis=-1)
    return -K.mean(left * right, axis=-1, keepdims=True)
def weighted_loss(y_true, y_pred):
    weights = y_true * weight_of_ones
    clipped_y_pred = K.clip(y_pred, K.epsilon(), None)
    weighted_cross_entropy = -(y_true * K.log(clipped_y_pred) * weights)
    result = K.mean(weighted_cross_entropy)
    return result
def weighted_accuracy(y_true, y_pred):
    weights = y_true * weight_of_ones
    weighted_equal = K.cast(K.equal(y_true, K.round(y_pred)),
                            K.floatx()) * weights
    return K.mean(weighted_equal)
示例#41
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 def _huber_loss(self, target, prediction):
     # sqrt(1+error^2)-1
     error = prediction - target
     return K.mean(K.sqrt(1 + K.square(error)) - 1, axis=-1)
 def loss(y_true, y_pred):
     return 1. / (image_sigma**2) * K.mean(K.square(y_true - y_pred))
示例#43
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        def vae_r_loss(y_true, y_pred):

            y_true_flat = K.flatten(y_true)
            y_pred_flat = K.flatten(y_pred)

            return 10 * K.mean(K.square(y_true_flat - y_pred_flat), axis = -1)
示例#44
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def negGrowthRateLoss(b, q):
    """ Customized loss function. """
    return (K.mean(-K.log(b + pow(-1, b) + pow(-1, b + 1) * q) / K.log(2.0)))
def normalization(x):
    mean = KR.mean(x**2)
    return x / KR.sqrt(2 * mean)  # 2 = number of NN into the channel
def normalize(x):
    # utility function to normalized a tensor by its L2 norm
    return x / (K.sqrt(K.mean(K.square(x))) + 1e-5)
print("\n\tDECODER STRUCTURE")
decoder.summary()

#**********AUTOENCODER STRUCTURE***************
out = decoder(encoder(inputs)[2])
vae = Model(inputs, out, name='vae')
vae.summary()

# Loss definition
rec_loss = mse(K.flatten(inputs), K.flatten(out))
rec_loss *= original_dim
KL_loss = 1 + z_log_var - K.square(z_mean) - K.exp(z_log_var)
KL_loss = K.sum(KL_loss, axis=-1)
KL_loss *= -0.5
vae_loss = K.mean(rec_loss + KL_loss) / original_dim

vae.add_loss(vae_loss)

my_opt = Adam(lr=1e-4)
vae.compile(optimizer=my_opt)


def my_generator(input_data, target, batch_size):
    # ----The generator for the train set----#
    while True:
        # Create empty arrays to contain batch of features and labels #
        batch_data = np.zeros(
            (batch_size, dataset.shape[1], dataset.shape[2], 1))
        batch_target = np.zeros(
            (batch_size, dataset.shape[1], dataset.shape[2], 1))
示例#48
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def filter_visualisation(iterations=20,
                         weights_path='imagenet',
                         layer='block5_conv1',
                         max_filters=200,
                         filters=8,
                         output_shape=224):
    """ Visualise convolutional filters of a CNN model by maximising their activations with gradient ascent.

    Args:
       iterations -- number of iterations of the gradient ascent procedure (Default: 20)
       weights_path -- path to the Keras CNN model (Default: imagenet model in Keras models directory)
       layer -- the network layer name whose activations are being shown. Use model.summary() to get names
       max_filters -- number of filters to be checked in layer
       filters -- determine the number of filters to be displayed (total: filters x filters)
       output_shape -- height and width of each output image showing activations (arranged in a grid)

    """

    img_width, img_height = output_shape, output_shape
    filter_indexes = range(0, max_filters)

    # By default, load the VGG16 network with ImageNet weights
    if weights_path == 'imagenet':
        model = vgg16.VGG16(weights=weights_path, include_top=False)
    else:
        model = load_model(weights_path)

    print('Model loaded.')

    # Display a summary of all the blocks
    model.summary()

    # This is the placeholder for the input images
    input_img = 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[0:]])

    kept_filters = []
    for filter_index in filter_indexes:

        # To speed up, scan only the first max_filters
        print('Processing filter %d' % filter_index)
        start_time = time.time()

        # Build a loss function that maximizes the activation of the nth filter of the layer considered
        layer_output = layer_dict[layer].output
        if K.image_data_format() == 'channels_first':
            loss = K.mean(layer_output[:, filter_index, :, :])
        else:
            loss = K.mean(layer_output[:, :, :, filter_index])

        # Compute the gradient of the input picture wrt this loss
        grads = K.gradients(loss, input_img)[0]

        def normalize(x):
            # Utility function to normalize a tensor by its L2 norm
            return x / (K.sqrt(K.mean(K.square(x))) + 1e-5)

        # Normalization trick: we normalize the gradient
        grads = normalize(grads)

        # This function returns the loss and grads given the input picture
        iterate = K.function([input_img], [loss, grads])

        # Step size for gradient ascent
        step = 1.

        # Start from a gray image with some random noise
        if K.image_data_format() == 'channels_first':
            input_img_data = np.random.random((1, 3, img_width, img_height))
        else:
            input_img_data = np.random.random(
                (1, img_width, img_height, model.input.shape[-1]))
        input_img_data = (input_img_data - 0.5) * 20 + 128

        # Run gradient ascent for 20 steps
        for i in range(iterations):
            loss_value, grads_value = iterate([input_img_data])
            input_img_data += grads_value * step

            print('Current loss value:', loss_value)
            if loss_value <= 0.:
                # some filters get stuck to 0, we can skip them
                break

        # Decode the resulting input image
        if loss_value > 0:
            img = deprocess_image(input_img_data[0])
            kept_filters.append((img, loss_value))
        end_time = time.time()
        print('Filter %d processed in %ds' %
              (filter_index, end_time - start_time))

    # Stich the best filters**2 filters on a filters x filters grid
    n = filters

    if filters**2 > len(kept_filters):
        n = int(np.floor(np.sqrt(len(kept_filters))))
    else:
        n = int(filters)

    # Filters that have the highest loss are assumed to be better-looking.
    kept_filters.sort(key=lambda x: x[1], reverse=True)
    kept_filters = kept_filters[:n * n]

    # Black picture with space for filters**2 filters with size output_shape x output_shape, 5px margin in between
    margin = 5
    width = n * img_width + (n - 1) * margin
    height = n * img_height + (n - 1) * margin
    stitched_filters = np.zeros((width, height, 3))

    # Fill the picture with our saved filters
    for i in range(n):
        for j in range(n):
            img, loss = kept_filters[i * n + j]
            stitched_filters[(img_width + margin) *
                             i:(img_width + margin) * i + img_width,
                             (img_height + margin) *
                             j:(img_height + margin) * j + img_height, :] = img

    # Save the result to disk
    imsave('stitched_filters_%dx%d.png' % (n, n), stitched_filters)

    return stitched_filters
示例#49
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def myloss(y_true, y_pred):

    return K.mean(K.square((y_pred - y_true) / y_true))
示例#50
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 def wasserstein_loss(self, y_true, y_pred):
     return K.mean(y_true * y_pred)
示例#51
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 def free_energy_gap(self, x_train, x_test):
     return K.mean(self.free_energy(x_train)) - K.mean(
         self.free_energy(x_test))
def root_mean_squared_error(y_true, y_pred):
  return K.sqrt(K.mean(K.square(y_pred - y_true)))
 def mean_error(y_true, y_pred):
     return K.mean(y_true - y_pred)
示例#54
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 def mse(y_true, y_pred):
     return K.mean(K.square((y_pred - avg_of_play_no_noise) - y_true))
示例#55
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def mseT(y_true, y_pred):
    return K.mean(K.square(y_pred - y_true), axis=(-4, -1))
示例#56
0
 def wasserstein(self, y_true, y_pred):
     return -K.mean(y_true * y_pred)
示例#57
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    def call(self, x):
        mean = K.mean(x, axis=self.axis, keepdims=True)
        std = K.std(x, axis=self.axis, keepdims=True) + self.epsilon

        return (x - mean) / std
示例#58
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# 解码层,也就是生成器部分
decoder_h = Dense(intermediate_dim, activation='relu')
decoder_mean = Dense(original_dim, activation='sigmoid')
h_decoded = decoder_h(z)
x_decoded_mean = decoder_mean(h_decoded)  # 估计的是每一个变量维度输出的均值

# 建立模型
vae = Model([x, y], [x_decoded_mean, yh])

# xent_loss是重构loss,kl_loss是KL loss
xent_loss = original_dim * metrics.binary_crossentropy(x, x_decoded_mean)

# 只需要修改K.square(z_mean)为K.square(z_mean - yh),也就是让隐变量向类内均值看齐
kl_loss = -0.5 * K.sum(
    1 + z_log_var - K.square(z_mean - yh) - K.exp(z_log_var), axis=-1)
vae_loss = K.mean(xent_loss + kl_loss)

# add_loss是新增的方法,用于更灵活地添加各种loss
vae.add_loss(vae_loss)
vae.compile(optimizer='rmsprop')
vae.summary()

vae.fit([x_train, y_train],
        shuffle=True,
        epochs=epochs,
        batch_size=batch_size,
        validation_data=([x_test, y_test], None))

# 构建encoder,然后观察各个数字在隐空间的分布
encoder = Model(x, z_mean)
def mase_loss(y_true, y_pred):
    return K.mean(
        K.abs(y_true - y_pred) /
        K.mean(K.abs(y_true - tf.gather(batches, global_step))))
示例#60
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 def vae_kl_loss(y_true, y_pred):
     return - 0.5 * K.mean(1 + vae_z_log_var - K.square(vae_z_mean) - K.exp(vae_z_log_var), axis = -1)