What video types does S3 Media Maestro support?

MediaElements.JS Media Types MIME Type(s)
Native video/audio video/mp4, audio/mp4, video/webm, audio/mpeg, audio/mp3, audio/ogg, audio/oga, video/ogg
Vimeo video/vimeo, video/x-vimeo
YouTube video/youtube, video/x-youtube

Keep in mind that each browser has limited support for each mime type. We highly recommend encoding video with h.264 as an MP4 because it is compatible across all major browsers.