Respecting recorded video orientation
The HTML5 video element in Internet Explorer 10 automatically orients videos based on the orientation metadata stored in the video (that is, whether it is in portrait or landscape mode). The metadata is set through the recording device, typically a camera or camera phone. There are no APIs or settings for this capability, but it is something that a developer should be aware of because it affects the layout of the video element on a page.
In this section
The track element enables you to add timed text tracks, such as closed captioning, translations, or text commentary, to HTML5 video elements.
Internet Explorer 10 Guide for Developers