cnnTesting.py

#Libraries we will need
from __future__ import division
import numpy as np
import os
from skimage import data
import matplotlib.pyplot as plt 

DATA_PATH = 'traffic/'

def load_data(dir):
    directories = [d for d in os.listdir(dir)
                  if os.path.isdir(os.path.join(dir,d))]
    labels = []
    images = []
    for d in directories:
        label_directory = os.path.join(dir, d)
        file_names = [os.path.join(label_directory, f)
                      for f in os.listdir(label_directory)
                      if f.endswith(".ppm")]
        for f in file_names:
            images.append(data.imread(f))
            labels.append(int(d))
    _labels = np.array(labels)
    return images,_labels




from skimage import transform
from skimage.color import rgb2gray


# Image rescaling and dataset batching
images28 = [transform.resize(image, (28, 28)) for image in images]
images28 = np.array(images28)
images28 = rgb2gray(images28)
images28_batches = np.vsplit(images28,25)
labels_batches = np.split(labels,25)
print np.shape(images28_batches)


#Simple NN architecture
#Accuracy after 3 epochs 0.505158730159
#define placeholder for our images and labels
x = tf.placeholder(dtype = tf.float32, shape = [None, 28, 28])
y = tf.placeholder(dtype = tf.int32, shape = [None])

#layer 1 -> flat an image to 1D vector
images_flat = tf.contrib.layers.flatten(x)
#Pass layer 1 answer to a fully connected layer with relu activations
logits = tf.contrib.layers.fully_connected(images_flat, 62, tf.nn.relu)

#Compute the loss
loss = tf.reduce_mean(tf.nn.sparse_softmax_cross_entropy_with_logits(labels = y, logits = logits))

#Minimize it with an optimizer
train_op = tf.train.AdamOptimizer(learning_rate=0.001).minimize(loss)

#Give me back the correct prediction for each training example. Remember the output is a 62 position vector
#with a probability distribution over the labels
correct_pred = tf.argmax(logits, 1)

# Compute accuracy for training
accuracy = tf.reduce_mean(tf.cast(correct_pred, tf.float32))

print("images_flat: ", images_flat)
print("logits: ", logits)
print("loss: ", loss)
print("predicted_labels: ", correct_pred)




#Convolutional architecture
#Accuracy after three epochs Accuracy: 0.922
#define placeholder for our images and labels
x = tf.placeholder(dtype = tf.float32, shape = [None, 28, 28])
y = tf.placeholder(dtype = tf.int32, shape = [None])

conv1_weights = tf.Variable(tf.truncated_normal([2, 2, 1, 32],
                                                stddev=0.1,seed=tf.set_random_seed(1234),
                                                dtype=tf.float32))

conv1_biases = tf.Variable(tf.zeros([32], dtype=tf.float32))
    
#this time we do not make our image flat, but let it as it is. 
input_layer = tf.reshape(x, [-1, 28, 28, 1])

  # Convolutional Layer #1
conv1 = tf.layers.conv2d(
      inputs=input_layer,
      filters=32,
      kernel_size=[5, 5],
      padding="same",
      activation=tf.nn.relu)

  # Pooling Layer #1
pool1 = tf.layers.max_pooling2d(inputs=conv1, pool_size=[2, 2], strides=2)

  # Convolutional Layer #2 and Pooling Layer #2
conv2 = tf.layers.conv2d(
      inputs=pool1,
      filters=64,
      kernel_size=[5, 5],
      padding="same",
      activation=tf.nn.relu)
pool2 = tf.layers.max_pooling2d(inputs=conv2, pool_size=[2, 2], strides=2)

  # Dense Layer
pool2_flat = tf.reshape(pool2, [-1, 7 * 7 * 64])
dense = tf.layers.dense(inputs=pool2_flat, units=1024, activation=tf.nn.relu)
dropout = tf.layers.dropout(inputs=dense, rate=0.4, training=True)

  # Logits Layer
logits = tf.layers.dense(inputs=dropout, units=62)

#Finally I flatten the image and pass it to a full dense layer so it can give me my probabily distribution

loss = tf.reduce_mean(tf.nn.sparse_softmax_cross_entropy_with_logits(labels = y, logits =logits))
train_op = tf.train.AdamOptimizer(learning_rate=0.001).minimize(loss)
correct_pred = tf.argmax(logits, 1)
accuracy = tf.reduce_mean(tf.cast(correct_pred, tf.float32))


print("images_flat: ", images_flat)
print("logits: ", logits)
print("loss: ", loss)
print("predicted_labels: ", correct_pred)