如何使CNN预测函数输出为二进制数（0或1）？

Question

我使用带有keras的CNN模型进行图像二进制分类，在最终预测部分，我在下面定义了这样的功能以输出预测结果：

model = keras.Sequential()
model.add(Conv2D(filters = 64, kernel_size = (3, 3), activation = 'relu', input_shape = ((256,256,3))))
model.add(MaxPooling2D(pool_size = (2, 2), strides=(2, 2)))
model.add(Conv2D(filters = 128, kernel_size = (3, 3), activation = 'relu'))
model.add(MaxPooling2D(pool_size = (2, 2), strides=(2, 2)))
model.add(Conv2D(filters = 256, kernel_size = (3, 3), activation = 'relu'))
model.add(MaxPooling2D(pool_size = (2, 2), strides=(2, 2)))
model.add(Flatten())
model.add(Dense(units = 512, activation = 'relu'))
model.add(Dense(units = 1,activation='sigmoid'))

model.compile(optimizer='adam', 
                      loss=tf.keras.losses.BinaryCrossentropy(),
                      metrics=['accuracy'])

history = model.fit(
    train_ds,
    validation_data=valid_ds,
    epochs=10)

def testing_image(image_directory):
    test_image = image.load_img(image_directory, target_size = (256, 256))
    test_image = image.img_to_array(test_image)
    test_image = np.expand_dims(test_image, axis = 0)
    result = model.predict(test_image)
    print(result)

testing_image('/content/drive/MyDrive/testing/01.jpg')

输出是：

[[0.4733843]]

输出始终是小数数字，但我希望输出输出结果结果。只有 0或1，而没有数组表示。

任何帮助都将受到赞赏。

Answer 1

sigmoid 激活功能返回0至1之间的值值＆lt; 0.5意味着零类（0）和＆gt; 0.5意味着二进制分类中的一（1）类。

要获取这些二进制数字，您需要在testing_image（）中添加一行代码，如下：

固定代码：

def testing_image(image_directory):
    test_image = image.load_img(image_directory, target_size = (256, 256))
    test_image = image.img_to_array(test_image)
    test_image = np.expand_dims(test_image, axis = 0)
#Changes in code
    pred = model.predict(test_image)
    result = np.where(pred > 0.5, 1, 0) #<--to get the binary category
    print(result)
testing_image('/content/drive/MyDrive/testing/01.jpg')