M4V Mimetype - video/mp4 or video/m4v?

Question

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/

Answer 1

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.

Answer 2

I only write HTML5 for special projects, but I've had a problem which I was able to solve quite by accident. In my blocks, I was writing the video code like this:

        <source src="Videos/myvideo.mp4" type="video/mp4">         <source src="Videos/myvideo.webm" type="video/webm"> 

Here was my problem: If I put the mp4 line first, Google Chrome would play the video part, but there would be no sound. If I put the webm line first, Google Chrome would play the video and sound correctly, but Apple Safari would not detect the video at all. Even if I added the codec information in the type= statement, it had no effect.

I was about to cave in and try to use Flash, but I happened on the solution, mostly by accident. In the line for mp4, I replaced the type="video/mp4" with type="video/m4v". It cured the problem completely! Note: I did not change the video file extentions from mp4 to m4v -- I only used m4v in the type= statement.

I couldn't find any documentation to tell me to do this, I just got interested in the difference between .mp4 and .m4v file extentions, and started playing around. I use Linux (Xubuntu) and I had created my videos as both webm and H.264 mp4 files, using Openshot Video Editor. Maybe the inner workings of Openshot caused this to be an issue, but anyway -- that's how I solved this problem. My mp4 videos play perfectly. I hope this helps somebody else -- MinnesotaJon