How to flip a data on an image?

I would like to flip the blue points upside down (in the attached image):

This is my code:

    hAxes = gca;
      % pixLoc(): a function that gets the locations 
      % of the desired pixels i.e. returns their columns and rows
      [cp,rp] = pixLoc(Ic,6,4,38,348); 
      % a black image with the same size of the image Ic
      imshow(imrotate(0*Ic,90)) 
      hold on
      % plotting points that I would like to flip 
      % (the blue points in the figure below)
      plot(hAxes,cp,rp,'o');
      hAxes.YDir = 'reverse';

I don't know why it's not flipped when I reversed the y-axis. Any help will be appreciated! Thanks!

Answer 1

[Image Analyst]

Maybe use

rp = size(Ic, 1) - rp;
plot(hAxes, cp, rp, 'o');

Answer 2

[Jan]

Or:

hAxes.YDir = 'normal';