python一个窗口中显示多张图像(matplotlib.pyplot)

import cv2 as cv
import numpy as np
import matplotlib.pyplot as plt
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def show_images(images, titles=None, num_cols=None, scale=3, normalize=False):
    """ 一个窗口中绘制多张图像:
    Args: 
        images: 可以为一张图像(不要放在列表中)，也可以为一个图像列表
        titles: 图像对应标题、
        num_cols: 每行最多显示多少张图像
        scale: 用于调整图窗大小
        normalize: 显示灰度图时是否进行灰度归一化
    """

    # 加了下面2行后可以显示中文标题
    plt.rcParams['font.sans-serif'] = ['SimHei']
    plt.rcParams['axes.unicode_minus'] = False

    # 单张图片显示
    if not isinstance(images, list):
        if not isinstance(scale, tuple):
            scale = (scale, scale * 1.5)

        plt.figure(figsize=(scale[1], scale[0]))
        img = images
        if len(img.shape) == 3:
            # opencv库中函数生成的图像为BGR通道，需要转换一下
            B, G, R = cv.split(img)
            img = cv.merge([R, G, B])
            plt.imshow(img)
        elif len(img.shape) == 2:
            # pyplot显示灰度需要加一个参数
            if normalize:
                plt.imshow(img, cmap='gray')
            else:
                plt.imshow(img, cmap='gray', vmin=0, vmax=255)
        else:
            raise TypeError("Invalid shape " +
                            str(img.shape) + " of image data")
        if titles is not None:
            plt.title(titles, y=-0.15)
        plt.axis('off')
        plt.show()
        return

    # 多张图片显示
    if not isinstance(scale, tuple):
        scale = (scale, scale)

    num_imgs = len(images)
    if num_cols is None:
        num_cols = int(np.ceil((np.sqrt(num_imgs))))
    num_rows = (num_imgs - 1) // num_cols + 1

    idx = list(range(num_imgs))
    _, figs = plt.subplots(num_rows, num_cols,
                           figsize=(scale[1] * num_cols, scale[0] * num_rows))
    for f, i, img in zip(figs.flat, idx, images):
        if len(img.shape) == 3:
            # opencv库中函数生成的图像为BGR通道，需要转换一下
            B, G, R = cv.split(img)
            img = cv.merge([R, G, B])
            f.imshow(img)
        elif len(img.shape) == 2:
            # pyplot显示灰度需要加一个参数
            if normalize:
                f.imshow(img, cmap='gray')
            else:
                f.imshow(img, cmap='gray', vmin=0, vmax=255)
        else:
            raise TypeError("Invalid shape " +
                            str(img.shape) + " of image data")
        if titles is not None:
            f.set_title(titles[i], y=-0.15)
        f.axes.get_xaxis().set_visible(False)
        f.axes.get_yaxis().set_visible(False)
    # 将不显示图像的fig移除，不然会显示多余的窗口
    if len(figs.shape) == 1:
        figs = figs.reshape(-1, figs.shape[0])
    for i in range(num_rows * num_cols - num_imgs):
        figs[num_rows - 1, num_imgs % num_cols + i].remove()
    plt.show()
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测试

单张图片

if __name__ == '__main__':
    src = cv.imread("image\\cat.jpg")
    title = "cat"
    show_images(src, title)
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多张图片

show_images([src]*4, [title]*4)
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多张图片(规定一行最多显示多少张图像)

show_images([src] * 4, [title] * 4, num_cols=3)
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