The officer does not have to show you the video in order to give you a citation.  However, you can request it via a discovery or open records request.... this is assuming that the video still exists.  If you want to see the video before you enter a plea, then you need to request it soon.  Many patrol videos loop over and are recorded over within 30-90 days.  Every department is a little different... so you need to find out their procedures and make the request for a copy of the video.