python3代码如下，

import os 
import sys 
import time 
import sys 
from PIL import Image 

def resize_image(input_image_path, output_image_path):
    original_image = Image.open(input_image_path)
    width, height = original_image.size
    new_size = (width // 2, height // 2)
    resized_image = original_image.resize(new_size)
    resized_image.save(output_image_path)
    return 

if __name__ == "__main__":
    start_t = time.time()
    
	resize_image("img1.png", "img2.png")

    end_t = time.time()
    print(f"used time: {(end_t - start_t) / 60.0} minutes!")

图像尺寸缩小一半，相机参数$f_x,f_y,c_x,c_y$都缩小一半，畸变参数无影响。