图片分类系统
图片分类系统
待分类图片为5类花朵图片,将图片分为训练数据集、测试数据集和验证数据集,训练数据集用于训练调参,测试数据集和训练数据集用于交叉验证。然后搭建网络训练数据并计算精确度。
import glob import os.path import random import numpy as np import tensorflow as tf from tensorflow.python.platform import gfile #1. 模型和样本路径的设置 BOTTLENECK_TENSOR_SIZE = 2048 SUMMARY_DIR = "E://log2" BOTTLENECK_TENSOR_NAME = 'pool_3/_reshape:0' JPEG_DATA_TENSOR_NAME = 'DecodeJpeg/contents:0' MODEL_DIR = 'E:\code\data' MODEL_FILE= 'tensorflow_inception_graph.pb' CACHE_DIR = '/datasets/bottleneck' INPUT_DATA = 'E:/flower_photos' VALIDATION_PERCENTAGE = 10 TEST_PERCENTAGE = 10 #2. 神经网络参数的设置 LEARNING_RATE = 0.01 STEPS = 2000 BATCH = 100 def variable_summaries(var, name): with tf.name_scope('summaries'): tf.summary.histogram(name, var) mean = tf.reduce_mean(var) tf.summary.scalar('mean/' + name, mean) stddev = tf.sqrt(tf.reduce_mean(tf.square(var - mean))) tf.summary.scalar('stddev/' + name, stddev) #3. 把样本中所有的图片列表并按训练、验证、测试数据分开 def create_image_lists(testing_percentage, validation_percentage): result = {} sub_dirs = [x[0] for x in os.walk(INPUT_DATA)] is_root_dir = True for sub_dir in sub_dirs: if is_root_dir: is_root_dir = False continue extensions = ['jpg', 'jpeg', 'JPG', 'JPEG'] file_list = [] dir_name = os.path.basename(sub_dir) for extension in extensions: file_glob = os.path.join(INPUT_DATA, dir_name, '*.' + extension) file_list.extend(glob.glob(file_glob)) if not file_list: continue label_name = dir_name.lower() training_images = [] testing_images = [] validation_images = [] for file_name in file_list:#遍历所有数据 base_name = os.path.basename(file_name) chance = np.random.randint(100) if chance < validation_percentage: validation_images.append(base_name) elif chance < (testing_percentage + validation_percentage): testing_images.append(base_name) else: training_images.append(base_name) result[label_name] = { 'dir': dir_name, 'training': training_images, 'testing': testing_images, 'validation': validation_images, } return result #4. 定义函数通过类别名称、所属数据集和图片编号获取一张图片的地址。 # 这个函数通过类别名称、所属数据集和图片编号获取一张图片的地址。 # image_lists参数给出了所有图片信息。 # image_dir参数给出了根目录。存放图片数据的根目录和存放图片特征向量的根目录地址不同。 # label_name参数给定了类别的名称。 # index参数给定了需要获取的图片的编号。 # category参数指定了需要获取的图片是在训练数据集、测试数据集还是验证数据集。 def get_image_path(image_lists, image_dir, label_name, index, category): label_lists = image_lists[label_name] category_list = label_lists[category] mod_index = index % len(category_list) base_name = category_list[mod_index] sub_dir = label_lists['dir'] full_path = os.path.join(image_dir, sub_dir, base_name) return full_path #5. 定义函数获取Inception-v3模型处理之后的特征向量的文件地址。 # 这个函数通过类别名称、所属数据集和图片编号获取经过Inception-v3模型处理之后的特征向量文件地址。 def get_bottleneck_path(image_lists, label_name, index, category): return get_image_path(image_lists, CACHE_DIR, label_name, index, category) + '.txt' # 6. 定义函数使用加载的训练好的Inception-v3模型处理一张图片,得到这个图片的特征向量。 def run_bottleneck_on_image(sess, image_data, image_data_tensor, bottleneck_tensor): bottleneck_values = sess.run(bottleneck_tensor, {image_data_tensor: image_data}) bottleneck_values = np.squeeze(bottleneck_values) return bottleneck_values #7. 定义函数会先试图寻找已经计算且保存下来的特征向量,如果找不到则先计算这个特征向量,然后#保存到文件。 def get_or_create_bottleneck(sess, image_lists, label_name, index, category, jpeg_data_tensor, bottleneck_tensor): # 获取一张图片对应的特征向量文件的路径。 label_lists = image_lists[label_name] sub_dir = label_lists['dir'] sub_dir_path = os.path.join(CACHE_DIR, sub_dir) if not os.path.exists(sub_dir_path): os.makedirs(sub_dir_path) bottleneck_path = get_bottleneck_path(image_lists, label_name, index, category) if not os.path.exists(bottleneck_path): image_path = get_image_path(image_lists, INPUT_DATA, label_name, index, category) image_data = gfile.FastGFile(image_path, 'rb').read() bottleneck_values = run_bottleneck_on_image(sess, image_data, jpeg_data_tensor, bottleneck_tensor) bottleneck_string = ','.join(str(x) for x in bottleneck_values) with open(bottleneck_path, 'w') as bottleneck_file: bottleneck_file.write(bottleneck_string) else: with open(bottleneck_path, 'r') as bottleneck_file: bottleneck_string = bottleneck_file.read() bottleneck_values = [float(x) for x in bottleneck_string.split(',')] return bottleneck_values #8. 这个函数随机获取一个batch的图片作为训练数据。 def get_random_cached_bottlenecks(sess, n_classes, image_lists, how_many, category, jpeg_data_tensor, bottleneck_tensor): bottlenecks = [] ground_truths = [] for _ in range(how_many): label_index = random.randrange(n_classes) label_name = list(image_lists.keys())[label_index] image_index = random.randrange(65536) bottleneck = get_or_create_bottleneck( sess, image_lists, label_name, image_index, category, jpeg_data_tensor, bottleneck_tensor) ground_truth = np.zeros(n_classes, dtype=np.float32) ground_truth[label_index] = 1.0 bottlenecks.append(bottleneck) ground_truths.append(ground_truth) return bottlenecks, ground_truths #9. 这个函数获取全部的测试数据,并计算正确率。 def get_test_bottlenecks(sess, image_lists, n_classes, jpeg_data_tensor, bottleneck_tensor): bottlenecks = [] ground_truths = [] label_name_list = list(image_lists.keys()) for label_index, label_name in enumerate(label_name_list): category = 'testing' for index, unused_base_name in enumerate(image_lists[label_name][category]): bottleneck = get_or_create_bottleneck(sess, image_lists, label_name, index, category,jpeg_data_tensor, bottleneck_tensor) ground_truth = np.zeros(n_classes, dtype=np.float32) ground_truth[label_index] = 1.0 bottlenecks.append(bottleneck) ground_truths.append(ground_truth) return bottlenecks, ground_truths #10. 定义主函数。 def main(_): image_lists = create_image_lists(TEST_PERCENTAGE, VALIDATION_PERCENTAGE) n_classes = len(image_lists.keys()) with gfile.FastGFile(os.path.join(MODEL_DIR, MODEL_FILE), 'rb') as f: graph_def = tf.GraphDef() graph_def.ParseFromString(f.read()) bottleneck_tensor, jpeg_data_tensor = tf.import_graph_def( graph_def, return_elements=[BOTTLENECK_TENSOR_NAME, JPEG_DATA_TENSOR_NAME]) bottleneck_input = tf.placeholder(tf.float32, [None, BOTTLENECK_TENSOR_SIZE], name='BottleneckInputPlaceholder') ground_truth_input = tf.placeholder(tf.float32, [None, n_classes], name='GroundTruthInput') with tf.name_scope('final_training_ops'): weights = tf.Variable(tf.truncated_normal([BOTTLENECK_TENSOR_SIZE, n_classes], stddev=0.001)) variable_summaries(weights,'/weights') biases = tf.Variable(tf.zeros([n_classes])) variable_summaries(biases, '/biases') logits = tf.matmul(bottleneck_input, weights) + biases tf.summary.histogram('/logits', logits) final_tensor = tf.nn.softmax(logits) tf.summary.histogram( '/final_tensor', final_tensor) with tf.name_scope('cross_entropy'): cross_entropy_mean=-tf.reduce_mean(ground_truth_input*tf.log(tf.clip_by_value(final_tensor,1e-10,1.0))) tf.summary.scalar('cross_entropy_mean',cross_entropy_mean) train_step = tf.train.GradientDescentOptimizer(LEARNING_RATE).minimize(cross_entropy_mean) with tf.name_scope('evaluation'): correct_prediction = tf.equal(tf.argmax(final_tensor, 1), tf.argmax(ground_truth_input, 1)) evaluation_step = tf.reduce_mean(tf.cast(correct_prediction, tf.float32)) merged = tf.summary.merge_all() with tf.Session() as sess: summary_writer = tf.summary.FileWriter(SUMMARY_DIR, sess.graph) init = tf.global_variables_initializer() sess.run(init) for i in range(STEPS): train_bottlenecks, train_ground_truth = get_random_cached_bottlenecks( sess, n_classes, image_lists, BATCH, 'training', jpeg_data_tensor, bottleneck_tensor) summary, _ =sess.run([merged,train_step], feed_dict={bottleneck_input: train_bottlenecks, ground_truth_input: train_ground_truth}) summary_writer.add_summary(summary, i) if i % 100 == 0 or i + 1 == STEPS: validation_bottlenecks, validation_ground_truth = get_random_cached_bottlenecks( sess, n_classes, image_lists, BATCH, 'validation', jpeg_data_tensor, bottleneck_tensor) validation_accuracy = sess.run(evaluation_step, feed_dict={ bottleneck_input: validation_bottlenecks, ground_truth_input: validation_ground_truth}) print('Step %d: Validation accuracy on random sampled %d examples = %.1f%%' % (i, BATCH, validation_accuracy * 100)) test_bottlenecks, test_ground_truth = get_test_bottlenecks( sess, image_lists, n_classes, jpeg_data_tensor, bottleneck_tensor) test_accuracy = sess.run(evaluation_step, feed_dict={ bottleneck_input: test_bottlenecks, ground_truth_input: test_ground_truth}) print('Final test accuracy = %.1f%%' % (test_accuracy * 100)) summary_writer.close() if __name__ == '__main__': main(_)
结果可视化
可以看到代价函数随迭代步数的增加而减小,分类精度随训练步数增加而增加
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