基于pytorch 的psnr和ssim计算：

import math
import numpy as np
from pytorch_msssim import ssim, ms_ssim, SSIM, MS_SSIM
import datetime
import os
import sysdef calc_psnr(sr, hr):diff = (sr - hr) / 255.00mse  = diff.pow(2).mean()psnr = -10 * math.log10(mse)                    return float(psnr)def calc_ssim(sr, hr):# def ssim(#     X,#     Y,#     data_range=255,#     size_average=True,#     win_size=11,#     win_sigma=1.5,#     win=None,#     K=(0.01, 0.03),#     nonnegative_ssim=False,# )ssim_val = ssim(sr, hr, data_range=255, size_average=True)return float(ssim_val)def cur_timestamp_str():#2024-0103-1121now = datetime.datetime.now()year = str(now.year)month = str(now.month).zfill(2)day = str(now.day).zfill(2)hour = str(now.hour).zfill(2)minute = str(now.minute).zfill(2)content = "{}-{}{}-{}{}".format(year, month, day, hour, minute)return content

关于ssim的计算，以及作为损失函数介绍，参考：
https://pypi.org/project/pytorch-msssim/#description