用cnn做行人分類
阿新 • • 發佈:2019-02-15
機器學習資料庫是關鍵,自己搜搜吧,規模太小訓練不出來,正樣本和負樣本。
訓練之前要處理訓練檔案,這個我在之前的python影象操作這篇博文裡寫過,並有完整程式碼。
也可以用我處理好的資料,稍後我會上傳
input_data.py
"""Functions for downloading and reading MNIST data.""" from __future__ import print_function import gzip import os import numpy def extract_images(filename): """Extract the images into a 4D uint8 numpy array [index, y, x, depth].""" print('Extracting', filename) rows = 128 cols = 64 data = numpy.fromfile(filename, dtype=numpy.uint8) data = data.reshape(-1, rows, cols, 1) #print numpy.shape(data) return data def dense_to_one_hot(labels_dense, num_classes=2): """Convert class labels from scalars to one-hot vectors.""" num_labels = labels_dense.shape[0] index_offset = numpy.arange(num_labels) * num_classes labels_one_hot = numpy.zeros((num_labels, num_classes)) labels_one_hot.flat[index_offset + labels_dense.ravel()] = 1 return labels_one_hot def extract_labels(filename, one_hot=False): """Extract the labels into a 1D uint8 numpy array [index].""" print('Extracting', filename) labels = numpy.fromfile(filename, dtype=numpy.uint8) if one_hot: return dense_to_one_hot(labels) return labels class DataSet(object): def __init__(self, images, labels, fake_data=False): if fake_data: self._num_examples = 10000 else: assert images.shape[0] == labels.shape[0], ( "images.shape: %s labels.shape: %s" % (images.shape, labels.shape)) self._num_examples = images.shape[0] # Convert shape from [num examples, rows, columns, depth] # to [num examples, rows*columns] (assuming depth == 1) assert images.shape[3] == 1 images = images.reshape(images.shape[0], images.shape[1] * images.shape[2]) # Convert from [0, 255] -> [0.0, 1.0]. images = images.astype(numpy.float32) images = numpy.multiply(images, 1.0 / 255.0) self._images = images self._labels = labels self._epochs_completed = 0 self._index_in_epoch = 0 @property def images(self): return self._images @property def labels(self): return self._labels @property def num_examples(self): return self._num_examples @property def epochs_completed(self): return self._epochs_completed def next_batch(self, batch_size, fake_data=False): """Return the next `batch_size` examples from this data set.""" if fake_data: fake_image = [1.0 for _ in xrange(784)] fake_label = 0 return [fake_image for _ in xrange(batch_size)], [ fake_label for _ in xrange(batch_size)] start = self._index_in_epoch self._index_in_epoch += batch_size if self._index_in_epoch > self._num_examples: # Finished epoch self._epochs_completed += 1 # Shuffle the data perm = numpy.arange(self._num_examples) numpy.random.shuffle(perm) self._images = self._images[perm] self._labels = self._labels[perm] # Start next epoch start = 0 self._index_in_epoch = batch_size assert batch_size <= self._num_examples end = self._index_in_epoch return self._images[start:end], self._labels[start:end] def read_data_sets(train_dir, fake_data=False, one_hot=False): class DataSets(object): pass data_sets = DataSets() if fake_data: data_sets.train = DataSet([], [], fake_data=True) data_sets.validation = DataSet([], [], fake_data=True) data_sets.test = DataSet([], [], fake_data=True) return data_sets TRAIN_IMAGES = 'train_data.bin' TRAIN_LABELS = 'train_label.bin' TEST_IMAGES = 'test_data.bin' TEST_LABELS = 'test_label.bin' VALIDATION_SIZE = 500 local_file =os.path.join(train_dir, TRAIN_IMAGES) train_images = extract_images(local_file) local_file =os.path.join(train_dir, TRAIN_LABELS) train_labels = extract_labels(local_file, one_hot=one_hot) local_file = os.path.join(train_dir, TEST_IMAGES) test_images = extract_images(local_file) local_file =os.path.join(train_dir, TEST_LABELS) test_labels = extract_labels(local_file, one_hot=one_hot) validation_images = train_images[:VALIDATION_SIZE] validation_labels = train_labels[:VALIDATION_SIZE] train_images = train_images[VALIDATION_SIZE:] train_labels = train_labels[VALIDATION_SIZE:] data_sets.train = DataSet(train_images, train_labels) data_sets.validation = DataSet(validation_images, validation_labels) data_sets.test = DataSet(test_images, test_labels) return data_sets
conv_net.py
import input_data mnist = input_data.read_data_sets('dataset', one_hot=True) import tensorflow as tf # Parameters learning_rate = 0.001 training_iters = 100000 batch_size = 128 display_step = 10 # Network Parameters n_input = 128*64 # data input (img shape: 128*64) n_classes = 2 # total classes (0-1) dropout = 0.50 # Dropout, probability to keep units # tf Graph input x = tf.placeholder(tf.float32, [None, n_input]) y = tf.placeholder(tf.float32, [None, n_classes]) keep_prob = tf.placeholder(tf.float32) #dropout (keep probability) # Create model def conv2d(img, w, b): return tf.nn.relu(tf.nn.bias_add(tf.nn.conv2d(img, w, strides=[1, 1, 1, 1], padding='SAME'),b)) def max_pool(img, k): return tf.nn.max_pool(img, ksize=[1, k, k, 1], strides=[1, k, k, 1], padding='SAME') def conv_net(_X, _weights, _biases, _dropout): # Reshape input picture _X = tf.reshape(_X, shape=[-1, 128, 64, 1]) # Convolution Layer conv1 = conv2d(_X, _weights['wc1'], _biases['bc1']) # Max Pooling (down-sampling) conv1 = max_pool(conv1, k=2) # Apply Dropout conv1 = tf.nn.dropout(conv1, _dropout) # Convolution Layer conv2 = conv2d(conv1, _weights['wc2'], _biases['bc2']) # Max Pooling (down-sampling) conv2 = max_pool(conv2, k=2) # Apply Dropout conv2 = tf.nn.dropout(conv2, _dropout) # Fully connected layer dense1 = tf.reshape(conv2, [-1, _weights['wd1'].get_shape().as_list()[0]]) # Reshape conv2 output to fit dense layer input dense1 = tf.nn.relu(tf.add(tf.matmul(dense1, _weights['wd1']), _biases['bd1'])) # Relu activation dense1 = tf.nn.dropout(dense1, _dropout) # Apply Dropout # Output, class prediction out = tf.add(tf.matmul(dense1, _weights['out']), _biases['out']) return out # Store layers weight & bias weights = { 'wc1': tf.Variable(tf.random_normal([5, 5, 1, 32])), # 5x5 conv, 1 input, 32 outputs 'wc2': tf.Variable(tf.random_normal([5, 5, 32, 64])), # 5x5 conv, 32 inputs, 64 outputs 'wd1': tf.Variable(tf.random_normal([32*16*64, 1024])), # fully connected, 7*7*64 inputs, 1024 outputs 'out': tf.Variable(tf.random_normal([1024, n_classes])) # 1024 inputs, 10 outputs (class prediction) } biases = { 'bc1': tf.Variable(tf.random_normal([32])), 'bc2': tf.Variable(tf.random_normal([64])), 'bd1': tf.Variable(tf.random_normal([1024])), 'out': tf.Variable(tf.random_normal([n_classes])) } # Construct model pred = conv_net(x, weights, biases, keep_prob) # Define loss and optimizer cost = tf.reduce_mean(tf.nn.softmax_cross_entropy_with_logits(pred, y)) optimizer = tf.train.AdamOptimizer(learning_rate=learning_rate).minimize(cost) # Evaluate model correct_pred = tf.equal(tf.argmax(pred,1), tf.argmax(y,1)) accuracy = tf.reduce_mean(tf.cast(correct_pred, tf.float32)) # Initializing the variables init = tf.initialize_all_variables() # Launch the graph with tf.Session() as sess: sess.run(init) step = 1 # Keep training until reach max iterations while step * batch_size < training_iters: batch_xs, batch_ys = mnist.train.next_batch(batch_size) # Fit training using batch data sess.run(optimizer, feed_dict={x: batch_xs, y: batch_ys, keep_prob: dropout}) if step % display_step == 0: # Calculate batch accuracy acc = sess.run(accuracy, feed_dict={x: batch_xs, y: batch_ys, keep_prob: 1.}) # Calculate batch loss loss = sess.run(cost, feed_dict={x: batch_xs, y: batch_ys, keep_prob: 1.}) print "Iter " + str(step*batch_size) + ", Minibatch Loss= " + "{:.6f}".format(loss) + ", Training Accuracy= " + "{:.5f}".format(acc) step += 1 print "Optimization Finished!" # Calculate accuracy for 256 mnist test images print "Testing Accuracy:", sess.run(accuracy, feed_dict={x: mnist.test.images[:256], y: mnist.test.labels[:256], keep_prob: 1.})
下面是訓練結果