Tensorflow，预期 conv2d_input 有 4 个维度

Question

我正在使用tf.keras，但出现以下错误：

ValueError：检查输入时出错：预期 conv2d_input 有 4 个维度，但得到了形状为 (24946, 50, 50) 的数组

有人可以帮我吗？

代码（IMAGE_SIZE是：50x50）

import tensorflow as tf
import numpy as np
import pickle
from tensorflow.keras.models import Sequential
from tensorflow.keras.layers import Dense, Dropout, Activation, Flatten, Conv2D, MaxPooling2D


pickle_ind = open("x.pickle", "rb")
x = pickle.load(pickle_ind)
x = np.array(x, dtype=float)
# x = x/255.0

pickle_ind = open("y.pickle", "rb")
y = pickle.load(pickle_ind)

n_batch = len(x)

model = Sequential()
model.add(Conv2D(32, (3, 3), activation='relu', input_shape=(50, 50, 1)))
model.add(MaxPooling2D((2, 2)))
model.add(Conv2D(64, (3, 3), activation='relu'))
model.add(MaxPooling2D((2, 2)))
model.add(Conv2D(64, (3, 3), activation='relu'))

model.summary()

model.compile(optimizer='adam',
              loss='binary_crossentropy',
              metrics=['accuracy'])

model.fit(x, y, epochs=20, batch_size=n_batch)