Create black columns/rows in image.

5 vues (au cours des 30 derniers jours)
Raldi
Raldi le 26 Fév 2015
Commenté : Raldi le 26 Fév 2015
Hi everyone,
I have an image and I want to only keep visible small patches of lets say 8x8 alternatively.
So I start at the beginning keep the first 8x8 patch, move right, make black the next patch, and so on until the end.
After that I move to the next row and I make the first patch black since we kept the one above it.
Moving like this I create a sort of a check board where the white parts have my original image.
What I did till now is
for ii = 1:it
Image = Image(1:step:end, 1:step:end);
end
After that I create a matrix of zeros at the dimensions of my original image and paint my under-sampled image
imageNew(1:step:end, 1:step:end) = Image;
This does not create the check-board effect though and I don't even know if it is good enough regarding the time it needs to run.
Has anyone any idea of how to go on about doing this?

Réponse acceptée

Guillaume
Guillaume le 26 Fév 2015
I would do it like this:
pattern = zeros(11, 10); %number of rows must be odd
pattern(1:2:end) = 1;
mycheckerboard = imresize(pattern, 30, 'nearest');
imshow(mycheckerboard)
  3 commentaires
Guillaume
Guillaume le 26 Fév 2015
Oh, sorry misunderstood. Just to this then:
mycheckerboard = imresize(pattern, size(myimage), 'nearest');
myimage = immultiply(myimage logical(mycheckerboard));
Raldi
Raldi le 26 Fév 2015
I am accepting this answer since it will help whoever read this to acieve what he want faster.

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Plus de réponses (1)

Image Analyst
Image Analyst le 26 Fév 2015
Why not simply use the checkerboard() function?????
  3 commentaires
Image Analyst
Image Analyst le 26 Fév 2015
Then I'd just create one line then use repmat twice. I would not use Image as the name of a variable since image() is the name of a built-in function.
Raldi
Raldi le 26 Fév 2015
I will try both suggestions and see how they work. Thanks for your time.

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