我使用标准的SVHN裁剪数字数据集生成了一个模型,该模型可以对10个可能的数字进行分类,在测试集上的准确率为89.89%。接下来,我想在图像上检测多个数字(例如,汽车牌照上的数字)。我应该如何操作?我是否需要重新训练我的模型以检测多个图像?
#conv1W_conv1 = weight_variable([5, 5, 1, 32])b_conv1 = bias_variable([32])x_image = tf.reshape(x, [-1,32,32,1])h_conv1 = tf.nn.relu(conv2d(x_image, W_conv1) + b_conv1)h_pool1 = max_pool_2x2(h_conv1)#conv2W_conv2 = weight_variable([5, 5, 32, 64])b_conv2 = bias_variable([64])h_conv2 = tf.nn.relu(conv2d(h_pool1, W_conv2) + b_conv2)h_pool2 = max_pool_2x2(h_conv2)#DenselyW_fc1 = weight_variable([8 * 8 * 64, 1024])b_fc1 = bias_variable([1024])h_pool2_flat = tf.reshape(h_pool2, [-1, 8*8*64])h_fc1 = tf.nn.relu(tf.matmul(h_pool2_flat, W_fc1) + b_fc1)#Dropoutkeep_prob = tf.placeholder(tf.float32)h_fc1_drop = tf.nn.dropout(h_fc1, keep_prob)#ReadoutW_fc2 = weight_variable([1024, 10])b_fc2 = bias_variable([10])y_conv = tf.matmul(h_fc1_drop, W_fc2) + b_fc2#Traincross_entropy = tf.reduce_mean(tf.nn.softmax_cross_entropy_with_logits(labels=y_, logits=y_conv))train_step = tf.train.AdamOptimizer(1e-4).minimize(cross_entropy)correct_prediction = tf.equal(tf.argmax(y_conv,1), tf.argmax(y_,1))accuracy = tf.reduce_mean(tf.cast(correct_prediction, tf.float32))sess.run(tf.global_variables_initializer())for i in range(40000): batch = shvn_data.nextbatch(100) if i%100 == 0: train_accuracy = accuracy.eval(feed_dict={ x:batch[0], y_: batch[1], keep_prob: 1.0}) print("step %d, training accuracy %f"%(i, train_accuracy)) train_step.run(feed_dict={x: batch[0], y_: batch[1], keep_prob: 0.5})
我的代码是从这里修改的: https://www.tensorflow.org/get_started/mnist/pros。我的代码可以在以下链接找到: https://github.com/limwenyao/ComputerVision/blob/testing/CNN_MNIST.py#L216
回答:
你可以在你的网络周围包装一个步进系统。因此,你可以将带有车牌的图像切割成许多更小的图像,然后在每个较小的图像上运行数字检测,记录找到的数字,最后将它们组合起来,瞧,你就得到了车牌号码。
这个将车牌图像切割成较小图像的过程通常也是一个训练过的网络。所以你将有两个网络:
- 一个学习如何正确切割
- 另一个学习从每个切割的子图像中读取一个数字