Make movie from imagesc

I have the following image:

t = 0:.1:10;

y4 = zeros(10,length(t));
x = zeros(size(t));
for k = 1:2:19999
   f(k)=k;
   x = x + sin(k*t)/k;
   y4((k+1)/2,:) = x;
end

y5=x-sin(t);

img2=imagesc(y5+1);
colormap('gray') ;

I would like to generate a movie to have the function moving on the x axis. I have tried im2frame which yields this error:

Error using im2frame
Can only make movie frames from image matrices of type double or uint8
F(1) = im2frame(img2);
Any help would be greatly appreciated!

[Image Analyst]

You only have one frame. How can you make a movie of only one frame? See attached demo.

[numnum]

Thank you! Yes, my idea was to make several frames, changing the CData

[Image Analyst]

What would be in the other frames?

[numnum]

The next frame could be maybe :

img3=img2
img3.Xdata=img2.Xdata+1

and so on

[numnum]

Thank you so much I've made this work ! Have a great day!