How to draw/change the color of 1 pixel in an image

I want to take an image into matlab and edit it by changing one pixel at a set of coordinates to a different color so as to identify points of interest on the image.

The plot function won't work as I am creating a video with a series of frames and implay.

Any help much appreciated

Answer 1

[Image Analyst]

rgbImage(row, column, :) = [r, g, b]; % r, g, b are uint8 values.
imshow(rgbImage);
drawnow; % Force it to paint right now

[TT Simmons]

Magic thank you!

[Shivani Pahuja]

the above code is giving error as Undefined function or variable 'r'.

Error in fill1 (line 3) rgbImage(row, column, :) = [r, g, b]; % r, g, b are uint8 values.

how to resolve it??

[Image Analyst]

If you're going to assign something, you have to have something to assign. What did you assign for r? Show me the line that says

r = 123;  % or whatever value you need.

I don't think you'll find that line, therefore there is no r to assign. What do you think it should assign? Just make up something? That's probably no good. You should make that decision.