用vgg13识别cifar100
import os
os.environ['TF_CPP_MIN_LOG_LEVEL']='2'
import tensorflow as tf
from tensorflow.keras import layers,optimizers,datasets,Sequential
tf.random.set_seed(2345)
conv_layers = [#5 unit of conv + max pooling
# unit 1
layers.Conv2D(64,kernel_size=[3,3],padding='same',activation=tf.nn.relu),
layers.Conv2D(64,kernel_size=[3,3],padding='same',activation=tf.nn.relu),
layers.MaxPool2D(pool_size=[2,2],strides=2,padding='same'),
layers.Conv2D(128,kernel_size=[3,3],padding='same',activation=tf.nn.relu),
layers.Conv2D(128,kernel_size=[3,3],padding='same',activation=tf.nn.relu),
layers.MaxPool2D(pool_size=[2,2],strides=2,padding='same'),
layers.Conv2D(256,kernel_size=[3,3],padding='same',activation=tf.nn.relu),
layers.Conv2D(256,kernel_size=[3,3],padding='same',activation=tf.nn.relu),
layers.MaxPool2D(pool_size=[2,2],strides=2,padding='same'),
layers.Conv2D(512,kernel_size=[3,3],padding='same',activation=tf.nn.relu),
layers.Conv2D(512,kernel_size=[3,3],padding='same',activation=tf.nn.relu),
layers.MaxPool2D(pool_size=[2,2],strides=2,padding='same'),
layers.Conv2D(512,kernel_size=[3,3],padding='same',activation=tf.nn.relu),
layers.Conv2D(512,kernel_size=[3,3],padding='same',activation=tf.nn.relu),
layers.MaxPool2D(pool_size=[2,2],strides=2,padding='same')
]
def preprocess(x,y):
x = tf.cast(x,dtype=tf.float32) / 255
y = tf.cast(y,dtype=tf.int32)
return x,y
(x,y) ,(x_test,y_test) = datasets.cifar100.load_data()
y = tf.squeeze(y,axis=1)
y_test = tf.squeeze(y_test,axis=1)
print(x.shape,x_test.shape)
train_db = tf.data.Dataset.from_tensor_slices((x,y));
train_db = train_db.shuffle(1000).map(preprocess).batch(16);
test_db = tf.data.Dataset.from_tensor_slices((x_test,y_test));
test_db = test_db.map(preprocess).batch(16);
sample = next(iter(train_db))
print('sample:',sample[0].shape,sample[1].shape)
sample = next(iter(test_db))
print('test_dbsample:',sample[0].shape,sample[1].shape)
def main():
conv_net = Sequential(conv_layers)
'''
x = tf.random.normal([4,32,32,3])
out = conv_net(x)
print(out.shape)
'''
fc_net = Sequential([
layers.Dense(256,activation=tf.nn.relu),
layers.Dense(128, activation=tf.nn.relu),
layers.Dense(100, activation=tf.nn.relu)
])
conv_net.build(input_shape=[None,32,32,3])
fc_net.build(input_shape=[None,512])
optimizer = optimizers.Adam(lr=1e-4)
variables = conv_net.trainable_variables + fc_net.trainable_variables
for epoch in range(50):
for step, (x, y) in enumerate(train_db):
#print(x.shape,y.shape)
with tf.GradientTape() as tape:
out = conv_net(x)
out =tf.reshape(out,[-1,512])
logits = fc_net(out)
y_hot = tf.one_hot(y,depth=100)
#loss
loss = tf.losses.categorical_crossentropy(y_hot,logits,from_logits=True)
loss = tf.reduce_mean(loss)
grads = tape.gradient(loss,variables)
optimizer.apply_gradients(zip(grads,variables))
if(step % 100 ==0):
print(epoch,step,"loss: ",float(loss))
total_sum = 0
total_currect = 0
for x,y in test_db:
out = conv_net(x)
out = tf.reshape(out,[-1,512])
logits = fc_net(out)
prob = tf.nn.softmax(logits,axis=1)
pred = tf.argmax(prob,axis=1)
pred = tf.cast(pred ,dtype=tf.int32)
correct = tf.cast(tf.equal(pred,y),dtype=tf.int32)
correct = tf.reduce_sum(correct)
total_sum += x.shape[0]
total_currect +=int(correct)
acc = total_currect / total_sum
print('acc: ',acc)
if __name__ == '__main__':
main()
完结撒花!!!