How can I find random pixels in an image?

Question

Faranak 2014-2-13

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/116015-how-can-i-find-random-pixels-in-an-image

评论： Image Analyst 2014-2-13

采纳的回答： Faranak

Hi all, I have a 256*256 pixels image and I want to have 5 randomly pixels in it.how can I do that?

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

Faranak 2014-2-13

I have some pixels with value more than 1 , I want to find randomly from those pixels. I tried this command : randi(size(imfinal),1,5) but it gives me random number of pixel number. I want exactly the number of i , j of the pixel,and those pixel which their value is more than 1 .

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Faranak 2014-2-13

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/116015-how-can-i-find-random-pixels-in-an-image#answer_124272

在 MATLAB Online 中打开

I found the answer,for those who want it:

%%% imfinal is the image

for i=1:256 for j=1:256 if imfinal(i,j)>2 f=imfinal;

        end
    end
end

%%%% 1800 is the total number of pixels with value more than 1

fo=find(f>20); rndm=randi(1800,1,5); fo2=fo(rndm);

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

Image Analyst 2014-2-13

That does not do what you asked. The first loop merely assigns the entire image to f. The second part looks at only the first 1800 pixels with a value of more than 20 and picks the linear index of 5 of them.

It doesn't give you "number of i , j of the pixel" and doesn't look at "those pixel which their value is more than 1". But whatever...as long as you're happy.

请先登录，再进行评论。