Exemple #1
0
Fichier : vae.py Projet : ag8/magic
    def _buildGraph(self):
        x_in = tf.placeholder(tf.float32, shape=[None,  # enables variable batch size
                                                 self.architecture[0]], name="x")
        dropout = tf.placeholder_with_default(1., shape=[], name="dropout")

        # encoding / "recognition": q(z|x)
        encoding = [Dense("encoding", hidden_size, dropout, self.nonlinearity)
                    # hidden layers reversed for function composition: outer -> inner
                    for hidden_size in reversed(self.architecture[1:-1])]
        h_encoded = composeAll(encoding)(x_in)

        # latent distribution parameterized by hidden encoding
        # z ~ N(z_mean, np.exp(z_log_sigma)**2)
        z_mean = Dense("z_mean", self.architecture[-1], dropout)(h_encoded)
        z_log_sigma = Dense("z_log_sigma", self.architecture[-1], dropout)(h_encoded)

        # kingma & welling: only 1 draw necessary as long as minibatch large enough (>100)
        z = self.sampleGaussian(z_mean, z_log_sigma)

        # decoding / "generative": p(x|z)
        decoding = [Dense("decoding", hidden_size, dropout, self.nonlinearity)
                    for hidden_size in self.architecture[1:-1]]  # assumes symmetry
        # final reconstruction: restore original dims, squash outputs [0, 1]
        decoding.insert(0, Dense(  # prepend as outermost function
            "x_decoding", self.architecture[0], dropout, self.squashing))
        x_reconstructed = tf.identity(composeAll(decoding)(z), name="x_reconstructed")

        # reconstruction loss: mismatch b/w x & x_reconstructed
        # binary cross-entropy -- assumes x & p(x|z) are iid Bernoullis
        rec_loss = VAE.crossEntropy(x_reconstructed, x_in)

        # Kullback-Leibler divergence: mismatch b/w approximate vs. imposed/true posterior
        kl_loss = VAE.kullbackLeibler(z_mean, z_log_sigma)

        with tf.name_scope("l2_regularization"):
            regularizers = [tf.nn.l2_loss(var) for var in self.sess.graph.get_collection(
                "trainable_variables") if "weights" in var.name]
            l2_reg = self.lambda_l2_reg * tf.add_n(regularizers)

        with tf.name_scope("cost"):
            # average over minibatch
            cost = tf.reduce_mean(rec_loss + kl_loss, name="vae_cost")
            cost += l2_reg

        # optimization
        global_step = tf.Variable(0, trainable=False)
        with tf.name_scope("Adam_optimizer"):
            optimizer = tf.train.AdamOptimizer(self.learning_rate)
            tvars = tf.trainable_variables()
            grads_and_vars = optimizer.compute_gradients(cost, tvars)
            clipped = [(tf.clip_by_value(grad, -5, 5), tvar)  # gradient clipping
                       for grad, tvar in grads_and_vars]
            train_op = optimizer.apply_gradients(clipped, global_step=global_step,
                                                 name="minimize_cost")

        # ops to directly explore latent space
        # defaults to prior z ~ N(0, I)
        with tf.name_scope("latent_in"):
            z_ = tf.placeholder_with_default(tf.random_normal([1, self.architecture[-1]]),
                                             shape=[None, self.architecture[-1]],
                                             name="latent_in")
        x_reconstructed_ = composeAll(decoding)(z_)

        return (x_in, dropout, z_mean, z_log_sigma, x_reconstructed,
                z_, x_reconstructed_, cost, global_step, train_op)
Exemple #2
0
    def _buildGraph(self):
        x_in = tf.placeholder(
            tf.float32,
            shape=[
                None,  # enables variable batch size
                self.architecture[0]
            ],
            name="x")
        dropout_prob = tf.placeholder_with_default(1.,
                                                   shape=[],
                                                   name="dropout_prob")

        # encoding / "recognition": q(z|x)
        encoding = [
            Dense("encoding", idx, hidden_size, dropout_prob,
                  self.nonlinearity)
            for hidden_size, idx in zip(self.architecture[1:-1],
                                        range(len(self.architecture) - 2))
        ]
        # hidden layers reversed for function composition: outer -> inner
        h_encoded = composeAll(reversed(encoding))(x_in)
        self.layerSummaries(encoding, x_in)

        # latent distribution parameterized by hidden encoding
        # z ~ N(z_mean, z_sigma**2)
        z_mean = Dense("z_mean",
                       len(self.architecture) - 2, self.architecture[-1],
                       1.)(h_encoded)
        z_sigma = Dense("z_sigma",
                        len(self.architecture) - 2, self.architecture[-1],
                        1.)(h_encoded)
        tf.summary.histogram('activations_z_mean', z_mean)
        tf.summary.histogram('activations_z_sigma', z_sigma)
        tf.summary.scalar('z_mean_mean-activations', tf.reduce_mean(z_mean))
        tf.summary.scalar('z_sigma_mean-activations', tf.reduce_mean(z_sigma))

        # kingma & welling: only 1 draw necessary as long as minibatch large enough (>100)
        z = self.sampleGaussian(z_mean, z_sigma)
        tf.summary.histogram('z_sampled', z)

        # decoding (p(x|z)): assuming architecture symmetry
        decoding = [
            Dense("decoding", idx, hidden_size, dropout_prob,
                  self.nonlinearity) for hidden_size, idx in zip(
                      self.architecture[1:-1],
                      reversed(
                          range(
                              len(self.architecture) -
                              1, 2 * len(self.architecture) - 3, 1)))
        ]
        # final reconstruction: prepend as outermost function
        decoding.insert(
            0,
            Dense("x_decoding", 2 * len(self.architecture) - 3,
                  self.architecture[0], 1.0, self.output_activation))
        x_reconstructed = tf.identity(composeAll(decoding)(z),
                                      name="x_reconstructed")
        self.layerSummaries(reversed(decoding), z)

        mse_autoencoderTest = tf.losses.mean_squared_error(
            x_reconstructed, x_in)
        sqrt_mse_autoencoderTest = tf.sqrt(mse_autoencoderTest)
        cosSim_autoencoderTest = self.cosSim(x_reconstructed, x_in)
        tf.summary.scalar('autoencoderTest_MSE', mse_autoencoderTest)
        tf.summary.scalar('autoencoderTest_sqrtMSE', sqrt_mse_autoencoderTest)
        tf.summary.scalar('autoencoderTest_cosSim', cosSim_autoencoderTest)

        # reconstruction loss: mismatch b/w x & x_reconstructed
        # binary cross-entropy -- assumes x & p(x|z) are iid Bernoullis
        rec_loss = VAE.crossEntropy(x_reconstructed, x_in)
        #rec_loss = VAE.l2_loss(x_reconstructed, x_in)
        tf.summary.scalar('cross_entropy', tf.reduce_mean(rec_loss))

        # Kullback-Leibler divergence: mismatch b/w approximate vs. imposed/true posterior
        kl_loss = VAE.kullbackLeibler(z_mean, z_sigma)
        tf.summary.scalar('KL_divergence', tf.reduce_mean(kl_loss))

        with tf.name_scope("l2_regularization"):
            regularizers = [
                tf.nn.l2_loss(var) for var in self.sesh.graph.get_collection(
                    "trainable_variables") if "weights" in var.name
            ]
            l2_reg = self.lambda_l2_reg * tf.add_n(regularizers)
        tf.summary.scalar('l2_reg', l2_reg)

        with tf.name_scope("cost"):
            # average over minibatch
            cost = tf.reduce_mean(rec_loss + kl_loss, name="vae_cost")
            tf.summary.scalar('cost_without_regularization', cost)
            cost += l2_reg
        tf.summary.scalar('cost', cost)

        # optimization
        total_updates = tf.Variable(0, trainable=False)
        #with tf.name_scope("Adam_optimizer"):
        with tf.name_scope("Adagrad_optimizer"):
            #optimizer = tf.train.AdamOptimizer(self.learning_rate)
            optimizer = tf.train.AdagradOptimizer(self.learning_rate)
            tvars = tf.trainable_variables()
            grads_and_vars = optimizer.compute_gradients(cost, tvars)
            clipped = [
                (tf.clip_by_value(grad, -5, 5), tvar)  # gradient clipping
                for grad, tvar in grads_and_vars
            ]
            train_op = optimizer.apply_gradients(grads_and_vars,
                                                 global_step=total_updates,
                                                 name="minimize_cost")

        # ops to directly explore latent space
        # defaults to prior z ~ N(0, I)
        with tf.name_scope("latent_in"):
            z_ = tf.placeholder_with_default(
                tf.random_normal([1, self.architecture[-1]]),
                shape=[None, self.architecture[-1]],
                name="latent_in")
        x_reconstructed_ = composeAll(decoding)(z_)

        return (x_in, dropout_prob, z_mean, z_sigma, x_reconstructed, z_,
                x_reconstructed_, cost, total_updates, train_op,
                mse_autoencoderTest, sqrt_mse_autoencoderTest,
                cosSim_autoencoderTest)
Exemple #3
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    def _buildGraph(self):
        x_in = tf.placeholder(tf.float32,
                              shape=[None, self.architecture[0]],
                              name="x")
        dropout = tf.placeholder_with_default(1., shape=[], name="dropout")

        # encoding / "recognition": q(z|x)
        encoding = [
            Dense("encoding", hidden_size, dropout, self.nonlinearity)
            for hidden_size in reversed(self.architecture[1:-1])
        ]
        h_encoded = composeAll(encoding)(x_in)

        # latent distribution parameterized by hidden encoding
        # z ~ N(z_mean, np.exp(z_log_sigma)**2)
        z_mean = Dense("z_mean", self.architecture[-1], dropout)(h_encoded)
        z_log_sigma = Dense("z_log_sigma", self.architecture[-1],
                            dropout)(h_encoded)

        z = self.sampleGaussian(z_mean, z_log_sigma)

        # decoding / "generative": p(x|z)
        decoding = [
            Dense("decoding", hidden_size, dropout, self.nonlinearity)
            for hidden_size in self.architecture[1:-1]
        ]
        # final reconstruction: restore original dims, squash outputs [0, 1] ???
        decoding.insert(
            0,
            Dense("x_decoding", self.architecture[0], dropout, self.squashing))
        x_reconstructed = tf.identity(composeAll(decoding)(z),
                                      name="x_reconstructed")

        # reconstruction loss
        rec_loss = VAE.crossEntropy(x_reconstructed, x_in)

        # Kullback-Leibler divergense
        kl_loss = VAE.kullbackLeibler(z_mean, z_log_sigma)

        with tf.name_scope("l2_regularization"):
            regularizers = [
                tf.nn.l2_loss(var) for var in self.sesh.graph.get_collection(
                    "trainable_variables") if "weights" in var.name
            ]
            l2_reg = self.lambda_l2_reg * tf.add_n(regularizers)

        with tf.name_scope("cost"):
            cost = tf.reduce_mean(rec_loss + kl_loss, name="vae_cost")
            cost += l2_reg

        # optimization
        global_step = tf.Variable(0, trainable=False)
        with tf.name_scope("Adam_optimizer"):
            optimizer = tf.train.AdamOptimizer(self.learning_rate)
            tvars = tf.trainable_variables()
            grads_and_vars = optimizer.compute_gradients(cost, tvars)
            clipped = [(tf.clip_by_value(grad, -5, 5), tvar)
                       for grad, tvar in grads_and_vars]
            train_op = optimizer.apply_gradients(clipped,
                                                 global_step=global_step,
                                                 name="minimize_cost")

        # ops to directly explore latent space, defaults to prior z ~ N(0, I)
        # FIXME x_reconstructedとx_reconstructed_の違いって何?
        with tf.name_scope("latent_in"):
            z_ = tf.placeholder_with_default(
                tf.random_normal([1, self.architecture[-1]]),
                shape=[None, self.architecture[-1]],
                name="latent_in")
        x_reconstructed_ = composeAll(decoding)(z_)

        return (x_in, dropout, z_mean, z_log_sigma, x_reconstructed, z_,
                x_reconstructed_, cost, global_step, train_op)
Exemple #4
0
    def _buildGraph(self):
        """
        x_in = tf.placeholder(tf.float32, shape=[None, # enables variable batch size
                                                 self.architecture[0]], name="x")
        """
        # get data from input pipeline
        filenames = []
        for root, dirs, files in os.walk(self.data_path):
            for file in files:
                filenames.append(os.path.join(root, file))

        f_tensor = tf.convert_to_tensor(filenames, dtype=tf.string)
        filename_queue = tf.train.string_input_producer(f_tensor)
        reader = tf.TextLineReader()
        key, value = reader.read(filename_queue)
        example = tf.decode_csv(value,
                                record_defaults=[[0]] * 1024,
                                field_delim='\t')
        example = tf.stack(example)
        """
        queue_batch=[]
        for i in range(10):
            key, value=reader.read(filename_queue)
            example=tf.decode_csv(value,record_defaults=[[0]]*1024,field_delim='\t')
            example=tf.stack(example)
            queue_batch.append(example)
        """
        x_q_in = tf.train.shuffle_batch([example],
                                        batch_size=self.batch_size,
                                        capacity=10000,
                                        num_threads=20,
                                        min_after_dequeue=200,
                                        allow_smaller_final_batch=True,
                                        enqueue_many=False)

        x_q_in_norm = tf.to_float(x_q_in) / 255.

        x_in = tf.placeholder_with_default(x_q_in_norm,
                                           shape=(None, 1024),
                                           name="x_in")

        dropout = tf.placeholder_with_default(1., shape=[], name="dropout")

        # encoding / "recognition": q(z|x)
        encoding = [
            Dense("encoding", hidden_size, dropout, self.nonlinearity)
            # hidden layers reversed for function composition: outer -> inner
            for hidden_size in reversed(self.architecture[1:-1])
        ]
        h_encoded = composeAll(encoding)(x_in)

        # latent distribution parameterized by hidden encoding
        # z ~ N(z_mean, np.exp(z_log_sigma)**2)
        z_mean = Dense("z_mean", self.architecture[-1], dropout)(h_encoded)
        z_log_sigma = Dense("z_log_sigma", self.architecture[-1],
                            dropout)(h_encoded)

        # kingma & welling: only 1 draw necessary as long as minibatch large enough (>100)
        z = self.sampleGaussian(z_mean, z_log_sigma)

        # decoding / "generative": p(x|z)
        decoding = [
            Dense("decoding", hidden_size, dropout, self.nonlinearity)
            for hidden_size in self.architecture[1:-1]
        ]  # assumes symmetry
        # final reconstruction: restore original dims, squash outputs [0, 1]
        decoding.insert(
            0,
            Dense(  # prepend as outermost function
                "x_decoding", self.architecture[0], dropout, self.squashing))
        x_reconstructed = tf.identity(composeAll(decoding)(z),
                                      name="x_reconstructed")

        # reconstruction loss: mismatch b/w x & x_reconstructed
        # binary cross-entropy -- assumes x & p(x|z) are iid Bernoullis
        rec_loss = VAE.crossEntropy(x_reconstructed, x_in)

        # Kullback-Leibler divergence: mismatch b/w approximate vs. imposed/true posterior
        kl_loss = VAE.kullbackLeibler(z_mean, z_log_sigma)

        with tf.name_scope("l2_regularization"):
            regularizers = [
                tf.nn.l2_loss(var) for var in self.sesh.graph.get_collection(
                    "trainable_variables") if "weights" in var.name
            ]
            l2_reg = self.lambda_l2_reg * tf.add_n(regularizers)

        with tf.name_scope("cost"):
            # average over minibatch
            cost = tf.reduce_mean(rec_loss + kl_loss, name="vae_cost")
            cost += l2_reg

        # optimization
        global_step = tf.Variable(0, trainable=False)

        with tf.name_scope("Adam_optimizer"):
            optimizer = tf.train.AdamOptimizer(self.learning_rate)
            tvars = tf.trainable_variables()
            grads_and_vars = optimizer.compute_gradients(cost, tvars)
            clipped = [
                (tf.clip_by_value(grad, -5, 5), tvar)  # gradient clipping
                for grad, tvar in grads_and_vars
            ]
            train_op = optimizer.apply_gradients(clipped,
                                                 global_step=global_step,
                                                 name="minimize_cost")

        # ops to directly explore latent space
        # defaults to prior z ~ N(0, I)
        with tf.name_scope("latent_in"):
            z_ = tf.placeholder_with_default(
                tf.random_normal([1, self.architecture[-1]]),
                shape=[None, self.architecture[-1]],
                name="latent_in")
        x_reconstructed_ = composeAll(decoding)(z_)

        return (x_in, dropout, z_mean, z_log_sigma, x_reconstructed, z_,
                x_reconstructed_, cost, global_step, train_op)
Exemple #5
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    def _buildGraph(self):
        x_in = tf.placeholder(tf.float32,
                              shape=(None, self.architecture[0]),
                              name="x_in")
        dropout = tf.placeholder_with_default(1., shape=(), name="dropout")

        # encoding / "recognition": q(z|x)
        encoding = [
            Dense("encoding",
                  hidden_size,
                  dropout,
                  self.nonlinearity,
                  initialization=self.initialization)
            # hidden layers reversed for function composition:
            # outer -> inner
            for hidden_size in reversed(self.architecture[1:-1])
        ]
        h_encoded = composeAll(encoding)(x_in)

        # latent distribution parameterized by hidden encoding
        # z ~ N(z_mean, np.exp(z_log_sigma)**2)
        z_mean = Dense("z_mean",
                       self.architecture[-1],
                       dropout,
                       initialization=self.initialization)(h_encoded)
        z_log_sigma = Dense("z_log_sigma",
                            self.architecture[-1],
                            dropout,
                            initialization=self.initialization)(h_encoded)

        # kingma & welling: only 1 draw necessary as long as
        # minibatch large enough (>100)
        z = tf.identity(self.sampleGaussian(z_mean, z_log_sigma), name="z")
        # this is also the entry point for latent space exploration

        # decoding / "generative": p(x|z)
        decoding = [
            Dense("decoding",
                  hidden_size,
                  dropout,
                  self.nonlinearity,
                  initialization=self.initialization)
            for hidden_size in self.architecture[1:-1]
        ]
        # assumes symmetry
        # final reconstruction: restore original dims
        # prepend as outermost function
        decoding.insert(
            0,
            Dense("x_decoding",
                  self.architecture[0],
                  dropout,
                  initialization=self.initialization))
        outer_layer = composeAll(decoding)(z)
        x_out = tf.nn.sigmoid(outer_layer, name="x_out")

        # reconstruction loss: mismatch b/w x & x_out
        # binary cross-entropy -- assumes x & p(x|z) are iid Bernoullis
        rec_loss = VAE.crossEntropy(outer_layer, x_in)

        # Kullback-Leibler divergence: mismatch b/w approximate
        # vs. imposed/true posterior
        kl_loss = VAE.kullbackLeibler(z_mean, z_log_sigma)

        with tf.name_scope("l2_regularization"):
            regularizers = [
                tf.nn.l2_loss(var) for var in self.sesh.graph.get_collection(
                    "trainable_variables") if "weights" in var.name
            ]
            l2_reg = self.lambda_l2_reg * tf.add_n(regularizers)

        with tf.name_scope("cost"):
            # average over minibatch plus l2 regularizer
            cost = tf.reduce_mean(rec_loss + kl_loss, name="vae_cost") + l2_reg

        # optimization
        global_step = tf.Variable(0, trainable=False)
        train_op = tf.contrib.layers.optimize_loss(
            cost,
            global_step,
            self.learning_rate,
            "Adam",
            clip_gradients=self.grad_clipping,
            name="trainer")

        return (x_in, dropout, z_mean, z_log_sigma, x_out, z, cost,
                global_step, train_op)