我是深度学习的初学者,正在构建一个程序,该程序可以根据其图像确定人。但是我的神经网络显示错误,我不知道如何解决-
model.fit(imgs_array,Y,batch_size = 401, epochs = 2, validation_split = 0.2)
File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/tensorflow/python/keras/engine/training.py", line 1527, in fit
x, y, sample_weights = self._standardize_user_data(
File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/tensorflow/python/keras/engine/training.py", line 991, in _standardize_user_data
x, y, sample_weights = self._standardize_weights(x, y, sample_weight,
File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/tensorflow/python/keras/engine/training.py", line 1149, in _standardize_weights
y = training_utils.standardize_input_data(
File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/tensorflow/python/keras/engine/training_utils.py", line 329, in standardize_input_data
raise ValueError(
ValueError: Error when checking target: expected dense_1 to have shape (5749,) but got array with shape (1,)
我的完整代码是
import os
import numpy as np
from tensorflow.keras.preprocessing.image import load_img, img_to_array
from sklearn.model_selection import train_test_split
from tensorflow.python import keras
from tensorflow.keras.utils import to_categorical
from tensorflow.python.keras.models import Sequential
from tensorflow.python.keras.layers import Dense, Flatten, Conv2D, Dropout
folders = os.listdir('lfw/')
# print(len(folders)) #5749
folders_a = np.asarray(folders)
image_files = []
X = []
Y = []
for folder in folders:
files = os.listdir('lfw/'+folder+'/') # type of files is a list
image_files.append(files)
for file in files:
X.append(file)
Y.append(folder)
# print(len(Y)) #13233
img_paths = []
for i in range(0,13233):
img_paths.append('lfw/'+Y[i]+'/'+X[i]) #img_paths is set now
print(len(img_paths))
imgs = []
for img_path in img_paths:
img_1 = load_img(img_path, color_mode="grayscale")
imgs.append(img_to_array(img_1))
# print(imgs[0].shape) #(250,250,1)
Y = np.array(Y)
# print(type(Y))
# print(Y.shape) #(13233,)
#Building Neural Network
imgs_array = np.array(imgs)
imgs_array /= 255
model = Sequential()
model.add(Conv2D(20, kernel_size = 3, activation = 'relu', input_shape =(250,250,1)))
model.add(Conv2D(20, kernel_size =3, activation = 'relu'))
model.add(Flatten())
model.add(Dense(401, activation = 'relu'))
model.add(Dense(5749,activation = 'softmax'))
print("compiling initiated")
model.compile(loss = 'mean_squared_error',optimizer = 'sgd')
print("model compiled")
model.fit(imgs_array,Y,batch_size = 401, epochs = 2, validation_split = 0.2)
错误的原因是什么以及如何解决?上面代码中的print(Y.shape)
行为我提供了输出(13233,)
。为什么在错误中显示(1, )
?
注意-我看到了下面给出的链接,但它们没有解决我的问题。
Error in fitting an RNN LSTM model
Error when checking target: expected dense_1 to have shape (1,) but got array with shape (256,)
快速浏览,我认为您的问题如下:您的网络将形状为(batch_size,250,250,1)的张量作为输入并给出形状为(batch_size,5749)的张量作为输出
[当您开始拟合时,keras会获取成批的输入数据和相应的标签,因此它会为您的形状为(batch_size,)+ imgs_array.shape [1:]的网络输入张量提供数据。和形状标签(batch_size,)+ Y.shape [1:]
即,对于该批次中的每个图像,您的标签都是标量(或者显然是一维矢量,我没有完全读过),并且您与之进行比较的输出是大小为5749的张量。不是标量。