这就是您正在寻找的答案：

def display_image_in_actual_size(im_path):

    dpi = 80
    im_data = plt.imread(im_path)
    height, width, depth = im_data.shape

    # What size does the figure need to be in inches to fit the image?
    figsize = width / float(dpi), height / float(dpi)

    # Create a figure of the right size with one axes that takes up the full figure
    fig = plt.figure(figsize=figsize)
    ax = fig.add_axes([0, 0, 1, 1])

    # Hide spines, ticks, etc.
    ax.axis('off')

    # Display the image.
    ax.imshow(im_data, cmap='gray')

    plt.show()

display_image_in_actual_size("./your_image.jpg")

改编自here。

约瑟夫的回答如下：显然，默认dpi更改为100，因此为了安全起见，将来可以直接从rcParams访问dpi，如下所示

import matplotlib as mpl
import matplotlib.pyplot as plt

def display_image_in_actual_size(im_path):

    dpi = mpl.rcParams['figure.dpi']
    im_data = plt.imread(im_path)
    height, width, depth = im_data.shape

    # What size does the figure need to be in inches to fit the image?
    figsize = width / float(dpi), height / float(dpi)

    # Create a figure of the right size with one axes that takes up the full figure
    fig = plt.figure(figsize=figsize)
    ax = fig.add_axes([0, 0, 1, 1])

    # Hide spines, ticks, etc.
    ax.axis('off')

    # Display the image.
    ax.imshow(im_data, cmap='gray')

    plt.show()

display_image_in_actual_size("./your_image.jpg")

如果要以实际大小显示图像，则子图中两个图像的实际像素大小相同，您可能只需要在子图定义中使用选项sharex和sharey

fig, ax = plt.subplots(nrows=1, ncols=2, figsize=(15, 7), dpi=80, sharex=True, sharey=True)
ax[1].imshow(image1, cmap='gray')
ax[0].imshow(image2, cmap='gray')

结果：

其中第二图像是第一图像的1/2大小。