import os
import random
import skimage.data
import skimage.transform
import matplotlib
import matplotlib.pyplot as plt
import numpy as np
import tensorflow as tf
def load_data(data_dir):
"""Loads a data set and returns two lists:
images: a list of Numpy arrays, each representing an image.
labels: a list of numbers that represent the images labels.
"""
# Get all subdirectories of data_dir. Each represents a label.
directories = [d for d in os.listdir(data_dir)
if os.path.isdir(os.path.join(data_dir, d))]
# Loop through the label directories and collect the data in
# two lists, labels and images.
labels = []
images = []
for d in directories:
label_dir = os.path.join(data_dir, d)
file_names = [os.path.join(label_dir, f)
for f in os.listdir(label_dir) if f.endswith(".ppm")]
# For each label, load it's images and add them to the images list.
# And add the label number (i.e. directory name) to the labels list.
for f in file_names:
images.append(skimage.data.imread(f))
labels.append(int(d))
return images, labels
# Load training and testing datasets.
train_data_dir = os.path.join( "Training")
test_data_dir = os.path.join( "Testing")
images, labels = load_data(train_data_dir)
print("Unique Labels: {0}\nTotal Images: {1}".format(len(set(labels)), len(images)))
def display_images_and_labels(images, labels):
"""Display the first image of each label."""
unique_labels = set(labels)
plt.figure(figsize=(15, 15)) #figsize参数可以指定绘图对象的宽度和高度
i = 1
for label in unique_labels:
# Pick the first image for each label.
image = images[labels.index(label)]
plt.subplot(8, 8, i) # A grid of 8 rows x 8 columns #面板设置成8行8列，并取第一个（顺时针编号）
plt.axis('off')
plt.title("Label {0} ({1})".format(label, labels.count(label)))
i += 1
_ = plt.imshow(image)
plt.show()
#display_images_and_labels(images, labels)
#for image in images[:5]:
# print("shape: {0}, min: {1}, max: {2}".format(image.shape, image.min(), image.max()))
# Resize images
images32=[skimage.transform.rescale(image,(32,32))
for image in images]
#display_images_and_labels(images32,labels)
for image in images32[:5]:
print("shape: {0}, min: {1}, max: {2}".format(image.shape, image.min(), image.max()))
labels_a = np.array(labels)
images_a = np.array(images32)
print("labels: ", labels_a.shape, "\nimages: ", images_a.shape)
# Create a graph to hold the model.
graph = tf.Graph()
# Create model in the graph.
with graph.as_default():
# Placeholders for inputs and labels.
images_ph = tf.placeholder(tf.float32, [None, 32, 32, 3])
labels_ph = tf.placeholder(tf.int32, [None])
# Flatten input from: [None, height, width, channels]
# To: [None, height * width * channels] == [None, 3072]
images_flat = tf.contrib.layers.flatten(images_ph)
# Fully connected layer.
# Generates logits of size [None, 62]
logits = tf.contrib.layers.fully_connected(images_flat, 62, tf.nn.relu)
# Convert logits to label indexes (int).
# Shape [None], which is a 1D vector of length == batch_size.
predicted_labels = tf.argmax(logits, 1)
# Define the loss function.
# Cross-entropy is a good choice for classification.
loss = tf.reduce_mean(tf.nn.sparse_softmax_cross_entropy_with_logits(logits, labels_ph))
# Create training op.
train = tf.train.AdamOptimizer(learning_rate=0.001).minimize(loss)
# And, finally, an initialization op to execute before training.
# TODO: rename to tf.global_variables_initializer() on TF 0.12.
init = tf.initialize_all_variables()
print("images_flat: ", images_flat)
print("logits: ", logits)
print("loss: ", loss)
print("predicted_labels: ", predicted_labels)
session =tf.Session(graph=graph)
_=session.run([init])
for i in range(201):
_,loss_value=session.run([train,loss],feed_dict={images_ph:images_a,labels_ph:labels_a})
if i %10 ==0:
print("loss:",loss_value)
""" 5001
oss: 0.966617
loss: 0.966603
loss: 0.966606
loss: 0.966592
loss: 0.96658
loss: 0.966586
loss: 0.966567
loss: 0.966557
loss: 0.966565
loss: 0.966548
loss: 0.966552
loss: 0.966536
loss: 0.966523
loss: 0.96652
loss: 0.966504
loss: 0.966503
loss: 0.966489
loss: 0.966498
loss: 0.966463
loss: 0.966484
"""
sample_indexes=random.sample(range(len(images32)),10)
sample_images=[images32[i] for i in sample_indexes]
sample_labels=[labels[i] for i in sample_indexes]
predicted=session.run([predicted_labels],feed_dict={images_ph:sample_images})[0]
print(sample_labels)
print(predicted)
fig=plt.figure(figsize=(10,10))
for i in range(len(sample_images)):
truth=sample_labels[i]
prediction=predicted[i]
plt.subplot(5,2,1+i)
plt.axis('off')
color='green' if truth==prediction else 'red'
plt.text(40,10,"Turth: {0}\n Prediction: {1}".format(truth,prediction),fontsize=12,color=color)
plt.imshow(sample_images[i])
test_images,test_labels=load_data(test_data_dir)
test_images32=[skimage.transform.resize(image,(32,32))
for image in test_images]
#display_images_and_labels(test_images32,test_labels)
predicted=session.run([predicted_labels],feed_dict={images_ph:test_images32})[0]
match_count=sum([int(y==y_) for y,y_ in zip(test_labels,predicted_labels)])
accuracy=match_count/len(test_labels)
print("Accuracy:{:.3f}".format(accuracy))
session.close()代码参考自
https://github.com/waleedka/traffic-signs-tensorflow/blob/master/notebook1.ipynb