You remember earlier Google launched Contextual Click-to-play Google Adsense Video Ads. I have yet to see a Google Adsense video ad on any website yet. But you can check out a demo / sample video advertisement.
See the sample Adsense video ad. A neat play button. Clickable url. Volume control. “Ads by Google” of course. The ad does not preload. You need to click the play button for it to start “buffering” and it plays only when the full ad is loaded. Then it does not replay automatically. If you press the play button again, it plays instantly, possibly because your browser has cached it. The volume control is a good idea too.
This is a sample ad, so you can click it. But if you see a similar video ad on your site – DO NOT CLICK on the advertiser’s URL, or the ad itself, it will be equivalent to clicking your own ads, generate invalid clicks and get your account banned. However, you can play and view the ads.