Find the maximum value on each color dimension (red, green, or blue) and plot a circle using that color. There may be more than one pixel with a maximum value; if so, pick one pixel at random.

*Find the maximum value on each color dimension (red, green, or blue) and plot a circle using that color. There may be more than one pixel with a maximum value; if so, pick one pixel at random.

For this task, I have imported a picture, added two annotations and subplotted each RGB component. However, I want to find the maximum value in each color dimension. I presume this number is a grayscale number, but I want to plot a circle with this color. *

%Import and plot picture of amsterdam

amsterdam = imread('amsterdam.bmp');
whos amsterdam;
imagesc(amsterdam)
hold on
plot ( [400 375], [75 325], 'r-d', 'linewidth', 4)
plot (375,480, 'm*','MarkerSize', 12)

title_color_components='RGB';
for subploti=1:4
    subplot(2,2,subploti)

    if subploti<4
        imagesc(amsterdam(:,:,subploti))

        title([ 'Plotting just the ' title_color_components(subploti) ' dimension.' ])
    else
        imagesc(amsterdam)
        title('Plotting all colors')
    end
end
max_red = max (max (amsterdam(:,:,1)));
max_green = max (max(amsterdam(:,:,2)));
max_blue = max (max(amsterdam(:,:,3)));
t = linspace(0,2*pi);
figure
plot(cos(t),sin(t), 'Color', [max_red max_green max_blue])

Answer 1

[Santhana Raj]

The property color in plot function takes input between 0 to 1. While your max color values are >1 usually. Try the below one:

plot(cos(t),sin(t), 'Color', [max_red/255 max_green/255 max_blue/255])