如何检查图像质量是否较低

import cv2
import numpy as np
from skimage.metrics import structural_similarity

def calculate_psnr(original_image_path, distorted_image_path):
    original_image = cv2.imread(original_image_path)
    distorted_image = cv2.imread(distorted_image_path)
    
    mse = np.mean((original_image - distorted_image) ** 2)
    if mse == 0:
        return float('inf')
    max_pixel = 255.0
    psnr = 20 * np.log10(max_pixel / np.sqrt(mse))
    return psnr

def calculate_ssim(original_image_path, distorted_image_path):
    original_image = cv2.imread(original_image_path, 0)
    distorted_image = cv2.imread(distorted_image_path, 0)
    
    ssim_index, _ = structural_similarity(original_image, distorted_image, full=True)
    return ssim_index

# 示例用法
original_image_path = 'path_to_original_image.jpg'
distorted_image_path = 'path_to_distorted_image.jpg'

psnr_value = calculate_psnr(original_image_path, distorted_image_path)
ssim_value = calculate_ssim(original_image_path, distorted_image_path)

print(f'PSNR: {psnr_value}')
print(f'SSIM: {ssim_value}')