negetive valu for PSNR after image enhancment in MATLAB

Question

fred bnm 2016-5-15

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/284335-negetive-valu-for-psnr-after-image-enhancment-in-matlab

评论： Image Analyst 2016-5-19

Hi, after image enhancement in frequency domain for assessment calculate psnr and value of psnr and snr is negative. class of input and output image is double.

 ref = imread('img.tif');
 ref=im2double(ref);
 %A = processing(ref);
 %Calculate the PSNR.
 [peaksnr, snr] = psnr(A, ref);

please guide me about valu of PSNR.

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Image Analyst 2016-5-16

1
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/284335-negetive-valu-for-psnr-after-image-enhancment-in-matlab#answer_222240

在 MATLAB Online 中打开

What is A??? And you forgot to attach img.tif and the "A" image, so I'm not going to do anything yet.

Since

PSNR=10log10(peakval^2/MSE)

and since you can't have negative values of PSNR unless MSE < peakValue^2, you must have A and ref on different scales, like you called im2double on one but not the other.