cv2下载链接：https://files.pythonhosted.org/packages/17/2f/d9cc975666db25dcc412b76f46510ece2bd921465a361336d441a8313dc6/opencv_python-3.4.3.18-cp36-cp36m-win_amd64.whl

#导入cv模块import cv2 as cv2#读取图像，支持 bmp、jpg、png、tiff 等常用格式image = cv2.imread('./a.jpg')#读取图像大小size=image.shapeprint('图像大小为',size)print(size[0])#创建窗口并显示图像,设定图像大小res=cv2.resize(image,(1000,2000),interpolation=cv2.INTER_CUBIC)#显示图像cv2.imshow('iker',res)#保存图像cv2.imwrite("./cat3.jpg", res, [int(cv2.IMWRITE_JPEG_QUALITY), 100])cv2.waitKey(0)#释放窗口cv2.destroyAllWindows()

 

#导入cv模块import cv2 as cv2#读取图像，支持 bmp、jpg、png、tiff 等常用格式def size(jpg,now_size):    image = cv2.imread(jpg)    # 读取图像大小    size = image.shape    print('图像大小为', size)    # 创建窗口并显示图像,设定图像大小    if size[0]>now_size:        beishu=size[0]/now_size        res=cv2.resize(image,(now_size,int(size[1]/beishu)),interpolation=cv2.INTER_CUBIC)        #显示图像        # cv2.imshow('iker',res)        #保存图像        cv2.imwrite("./cat3.jpg", res, [int(cv2.IMWRITE_JPEG_QUALITY), 100])        # cv2.waitKey(0)        #释放窗口        # cv2.destroyAllWindows()    else:        print('图像不用缩小')def main():    now_size = 500    jpg=r'./a.jpg'    size(jpg, now_size)if __name__ == '__main__':    main()