How can I set the generated figure into full screen and have it shown in projector without any white base or frame?

I am trying to create a program that can read a bmp image and have it patterned to be 3 in a row. Then move it from right to left at specific pixels per second. Then I need this to be shown in a projector. I already figured out how to generate the patterned image and moving at specific speed. But I still cannot make this program shown full-screen and also into the projector. I am very new to Matlab and coding. The finished program is here

I = imread('layer40.bmp');      %read image
resized = I(129-128:800,322:1280-320);  %resize image
Blackimage = 0 * resized;       %create black image as the same size
repeated = [Blackimage,Blackimage,resized,resized,resized,Blackimage,Blackimage];
figure;
for t = 0:14200
    x = 1 + 6*t;
    subimage = repeated(1:800, x:(x+1280));
    imshow(subimage)
end

Could anyone help me out with the full screen and projection? I really appreciate any of your help!!