基于pytorch 的psnr和ssim计算

基于pytorch 的psnr和ssim计算：

sr，hr是 NCHW格式的tensor, uint8 0-255

import math
import numpy as np
from pytorch_msssim import ssim, ms_ssim, SSIM, MS_SSIM
import datetime
import os
import sys

def calc_psnr(sr, hr):
    diff =