How to figure a colour based on a matrice of 1-by-3
1 vue (au cours des 30 derniers jours)
Afficher commentaires plus anciens
This is my code:
%%In this part we just find the coordinates of the required colours
im = imread('Lighthouse.jpg');
n = 4;
figure, imshow(im)
[x,y] = ginput(n);
x = floor(x);
y = floor(y);
%colour(length(x),3);
for i=1:length(x)
for j=1:3
colour(i,j) = im(y(i),x(i),j);
end
end
image(colour)
when I run it, and slect a point on the image it doesn't show me the colour I selected!! it figures a red colour!! why is that? the variable colour is [195,213,223]
how can I visualize that RGB colour?
0 commentaires
Réponse acceptée
Image Analyst
le 20 Oct 2011
Well you messed up in a couple of places. Try this:
im = imread('peppers.png');
n = 4;
figure, imshow(im)
[x,y] = ginput(n);
x = floor(x);
y = floor(y);
%colour(length(x),3);
colour = zeros(length(x), 1, 3, 'uint8');
for i=1:length(x)
for j=1:3
colour(i,1, j) = im(y(i),x(i),j);
end
end
image(colour)
Plus de réponses (2)
the cyclist
le 20 Oct 2011
Divide by 255. MATLAB uses the convention of RGB values from (0,1). This was discussed on this forum a few weeks ago, but for some reason I can't find it.
Walter Roberson
le 20 Oct 2011
Before the loop, initialize
colour = zeros(length(x),3, 'uint8');
You will then not need to do the division by 255 that The Cyclist refers to.
2 commentaires
Walter Roberson
le 20 Oct 2011
You are selecting 4 points so you should be getting 4 colors.
You need to check whether your file is RGB (truecolor) or an indexed image (2D but you have to read in the colormap as well.)
Voir également
Catégories
En savoir plus sur Convert Image Type dans Help Center et File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!