M4V Mimetype - video/mp4 or video/m4v?
html, mime-types, video
Solution
The standard media type is `video/mp4`.
The standard mp4 container format is commonly used for both AAC audio, and H.264 video + AAC audio. These have different media types, `audio/mp4` and `video/mp4`, however often you want different applications for audio and video and on some systems it is only possible to associate a default application with a file extension. Therefore it has become popular in some circles to use the extensions `.m4a` and `.m4v` for audio and video(+audio), respectively, in an mp4 container. However this does not affect the media type, which already distinguishes these using the audio or video prefix.
A twist, however, is that Apple started using their own media type, `video/x-m4v`, for videos from their store, which are in an mp4 container and use a `.m4v` extension. This is set to open the video in iTunes by default. Sometimes that is necessary because the video uses DRM, AC-3 Dolby Digital audio, or other capabilities that are not commonly supported in an mp4 container, but which are supported by iTunes for files with a `.m4v` extension. If you rely on such capabilities then you may want to use this media type instead of the standard one.
Media types with no `x-` are standardized in an RFC and tracked by IANA. No media type with the name `video/m4v` has been standardized. Non-standard media types have a `x-` prefix.
Problem
I am serving a video via the HTML5 `video` element. I'm finding conflicting information about the appropriate MIME type for `m4v` video. Most demos set the `type` attribute to `video/mp4` in the `source` tag in the markup. Some articles I've read indicate `video/m4v` for the web server Mimetype, while others indicate `video/mp4`. Which is correct? See for example, this article indicating `video/m4v` mimetype: http://html5center.sourceforge.net/make-your-html5-video-play-on-mobile-devices And this article indicating `video/mp4`: http://www.coolestguyplanettech.com/use-html-5-video-on-all-browsers/