fogg density Df of an image in matlab

Iam working on image processing and i want tabulate how much i enhanced the given input foggy image to output deffoged image,Is fogg density is the thing i want to find? if it is How to find fogg density Df of a foggy image.

Answer 1

[Subhadeep Koley]

Hi, I assume you are trying to find fog density, prior to defogging the foggy image.

A function named imreducehaze() comes inbuilt starting from MATLAB 2017b. This function returns fog density at each pixel of an image. The following code might help.

A = imread('foggysf1.jpg'); % Read your foggy image here
[~,T,~] = imreducehaze(A); % T is the fog density at each pixel
figure; imshow(T,[]);

Or, if you are looking for quantitative fog removal evaluation descriptor the refer to the link below.

https://www.mathworks.com/matlabcentral/fileexchange/33529-a-new-visibility-metric-for-haze-images

Answer 2

[Prithviraj M.K.]

Subhadeep Koley,thanks for your answer,but i need to find a parameter that will show the difference between foggy image and the deffoged image.

that is

FRF=Df-Ddf,where Df is the fogg density of the foggy image and Ddf is the fogg density of the enhanced or deffoged image.

[Subhadeep Koley]

Yes, like I said previously if you are looking for quantitative fog removal evaluation descriptor the refer to the link below.

https://www.mathworks.com/matlabcentral/fileexchange/33529-a-new-visibility-metric-for-haze-images

Using that function you can get a number (Contrast-to-Noise Ratio) for both the foggy and defogged images.

Higher the Contrast-to-Noise Ratio better the defogging efficiency.