Setup HTML attributes as width, height, poster, id, class, src
Setup HTML attributes as width, height, poster, id, class, src
If $type is video and is only set width or height then calculate the missing dimension to fit 16/9.
The 'id' is set as 'video_nickname' or 'audio_nickname' if $obj['nickname'] exists else video_ or audio_ are followed by an hash
If the same $obj is embed many times 'video_nickname' or 'audio_nickname' is suffixed with an hash to avoid id collision
If missing $obj['mime_type'] the $attributes['src'] is set.
In this way it will be placed in <video src=""> or <audio src=""> and video.js will try to use it.
AppHelper