How to use Videofile in matlab

Hello! I can use the frames of my videofile by:

MV = mmreader(My videofile); %To read Movie

for num=SF:STEP:EF

img(:,:,:,num) = read(MV,num); %reading particular frame

and after I make changes to this frames I show the results by - imshow(FRAME);

how can I show my frames that have been changed like a new video window and not like an images?

Thank you