I want to use a 4:3 video as a background on a site, but setting the width and height to 100% doesnt work, since the aspect ratio is kept intact, so the video doesnt fill th
http://dev.opera.com/articles/view/everything-you-need-to-know-about-html5-video-and-audio/
[...] in the same way as the img element — if you only set one of width and height, the other dimension is automatically adjusted appropriately so that the video retains its aspect ratio. However — unlike the img element — if you set width and height to something that doesn't match the aspect ratio of the video, the video is not stretched to fill the box. Instead, the video retains the correct aspect ratio and is letterboxed inside the video element. The video will be rendered as large as possible inside the video element while retaining the aspect ratio.