利用Conv网络,实现10种物体类别的分类,数据集为item_10(类似cifar100) 算法预处理: 导入tf库 打开原始数据文件 load训练数据并关闭文件 读取b'data'并处理 读取b'labels'并处理 切分数据集 算法定义和训练: 定义展为符XY 定义首层conv层 定义二层conv层 输出展平 构建全连结 设定损失 设定反向传播优化器 定义模型准确率 训练网络 验证测试准确率
时间: 2024-03-15 09:43:46 浏览: 79
这是一个利用卷积神经网络实现10种物体类别分类的示例代码,具体实现过程如下:
```python
import tensorflow as tf
import numpy as np
# 打开数据文件
with open('item_10.bin', 'rb') as f:
# 读取训练数据
train_data = np.fromfile(f, dtype=np.uint8).reshape(-1, 3072)
train_data = np.float32(train_data) / 255.0
# 读取训练标签
train_labels = np.fromfile(f, dtype=np.uint8)
# 切分数据集
train_size = int(len(train_data) * 0.8)
train_x, train_y = train_data[:train_size], train_labels[:train_size]
test_x, test_y = train_data[train_size:], train_labels[train_size:]
# 定义占位符
x = tf.placeholder(tf.float32, [None, 32*32*3])
y = tf.placeholder(tf.int64, [None])
# 定义第一层卷积层
conv1_weights = tf.get_variable("conv1_weights", [5, 5, 3, 32], initializer=tf.truncated_normal_initializer(stddev=0.1))
conv1_biases = tf.get_variable("conv1_biases", [32], initializer=tf.constant_initializer(0.0))
conv1 = tf.nn.conv2d(tf.reshape(x, [-1, 32, 32, 3]), conv1_weights, strides=[1, 1, 1, 1], padding='SAME')
relu1 = tf.nn.relu(tf.nn.bias_add(conv1, conv1_biases))
pool1 = tf.nn.max_pool(relu1, ksize=[1, 2, 2, 1], strides=[1, 2, 2, 1], padding='SAME')
# 定义第二层卷积层
conv2_weights = tf.get_variable("conv2_weights", [5, 5, 32, 64], initializer=tf.truncated_normal_initializer(stddev=0.1))
conv2_biases = tf.get_variable("conv2_biases", [64], initializer=tf.constant_initializer(0.0))
conv2 = tf.nn.conv2d(pool1, conv2_weights, strides=[1, 1, 1, 1], padding='SAME')
relu2 = tf.nn.relu(tf.nn.bias_add(conv2, conv2_biases))
pool2 = tf.nn.max_pool(relu2, ksize=[1, 2, 2, 1], strides=[1, 2, 2, 1], padding='SAME')
# 输出展平
flatten = tf.reshape(pool2, [-1, 8*8*64])
# 构建全连接层
fc1_weights = tf.get_variable("fc1_weights", [8*8*64, 1024], initializer=tf.truncated_normal_initializer(stddev=0.1))
fc1_biases = tf.get_variable("fc1_biases", [1024], initializer=tf.constant_initializer(0.1))
fc1 = tf.nn.relu(tf.matmul(flatten, fc1_weights) + fc1_biases)
# 构建输出层
fc2_weights = tf.get_variable("fc2_weights", [1024, 10], initializer=tf.truncated_normal_initializer(stddev=0.1))
fc2_biases = tf.get_variable("fc2_biases", [10], initializer=tf.constant_initializer(0.1))
logits = tf.matmul(fc1, fc2_weights) + fc2_biases
# 定义损失函数
cross_entropy = tf.nn.sparse_softmax_cross_entropy_with_logits(logits=logits, labels=y)
loss = tf.reduce_mean(cross_entropy)
# 定义反向传播优化器
optimizer = tf.train.AdamOptimizer(1e-4).minimize(loss)
# 定义模型准确率
correct_prediction = tf.equal(tf.argmax(logits, 1), y)
accuracy = tf.reduce_mean(tf.cast(correct_prediction, tf.float32))
# 训练网络
batch_size = 128
epochs = 10
num_batches = len(train_x) // batch_size
with tf.Session() as sess:
sess.run(tf.global_variables_initializer())
for epoch in range(epochs):
for i in range(num_batches):
batch_x, batch_y = train_x[i*batch_size:(i+1)*batch_size], train_y[i*batch_size:(i+1)*batch_size]
_, loss_val = sess.run([optimizer, loss], feed_dict={x: batch_x, y: batch_y})
if i % 100 == 0:
acc_val = sess.run(accuracy, feed_dict={x: test_x, y: test_y})
print("Epoch: %d, Batch: %d/%d, Loss: %f, Test Accuracy: %f" % (epoch, i, num_batches, loss_val, acc_val))
test_acc_val = sess.run(accuracy, feed_dict={x: test_x, y: test_y})
print("Final Test Accuracy: %f" % test_acc_val)
```
在这个示例代码中,我们使用了两层卷积层和两层全连接层构建了一个简单的卷积神经网络模型,对10种不同物体类别进行分类。其中,第一层卷积层的卷积核大小为 5x5x3,数量为 32;第二层卷积层的卷积核大小为 5x5x32,数量为 64;全连接层的隐藏节点数为 1024。在训练过程中,我们使用 Adam 优化器对损失函数进行反向传播,并统计模型在测试集上的准确率。
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