3D Numpy数组到灰度图片

Question

while extracting the cifar10 dataset im confronted by arrays with the dimension of 32x32x3.

i can plot the image in colour with eg plt.imshow(train_data[2]); whats a common way to transform the array to the dimension 32x32 with grayscale values?

train_data, train_labels, test_data, test_labels = 
load_cifar10_data(data_dir)

print(train_data.shape)
print(train_labels.shape)

output:

(50000, 32, 32, 3) (50000,)

meanwhile, i'm just saving the images and read them again, but i guess there is a by far more elegant way to directly store the pictures to grayscale.

Answer 1

You can use your current 3D array to plot a grayscale image using matplotlib's imshow as described here .

import matplotlib.pyplot as plt
plt.imshow(train_data , cmap = "gray")