Does the html5 audio tag encompass .mid (MIDI) uno

问题:

It seems clear that officially the html5 audio tag is intended for use with the ogg format.

Does the html5 audio tag encompass .mid (MIDI) unofficially?

回答1:

Updates:

This is a somewhat old question but it is still highly ranked on Google so here are some updates to the answers above - standards and tools that may have not been available when the question was asked but may be useful to people who find this question today:

• Web MIDI API (this is currently a W3C Editor's Draft from December 26, 2012 - ie. today - so it may change)
• MIDI.js - playing MIDI with JavaScript
• jasmid - MIDI synthesis with JavaScript

See also those questions:

• Generate live MIDI from Javascript
• generating MIDI in javascript

回答2:

In spite of the MIME type "audio/midi" a MIDI file is not audio ... it is a musical performance only, there is no sound. In other words, a MIDI file stores which keys a piano player hit, when he or she hit them, and how hard he or she hit them, but no actual piano sounds. You have to put the musical performance through a sampler that has a piano sound in it, just like you have to put a piano roll through a player piano. Apple QuickTime 7 has such a sampler built-in, but I don't know if QuickTime X does. Anyway, you would have to use an embed tag, it doesn't work through the audio tag.

It seems clear that officially the html5 audio tag is intended for use with the ogg format.

No. HTML5 is a markup standard. It doesn't address audio standardization at all. In other words, it tells you how to encode markup, not how to encode audio. Audio standardization is done by ISO's Moving Picture Experts Group for the past 20 years now. The current audio standard is MPEG-4 AAC (audio/mp4), and the previous standard is MPEG-2 MP3 (audio/mp3). If you are standardizing your markup to the W3C HTML5 specification, then you should standardize your audio to the ISO MPEG-4 specification. Otherwise, just ignore all standards and use whatever markup and audio you like, and make content that only you can see. All PC's and mobiles support both HTML5 and MPEG-4 out-of-the-box. It is only the alternate browsers that block access to the user's hardware MPEG-4 player, so you should work around those by offering the MP4 audio file to those users as a simple link they can click and open in a helper app, like iTunes (which is on about 90% of all PC's). Or you can invoke a FlashPlayer in those alternate browsers and load the same standard MP4 in there.

As for Ogg, it plays in some alternate browsers, but it doesn't play in the user's RSS reader, Podcast reader, native apps that offer Web views, and in many other contexts that the user may see your web page. Standardized audio plays in all of those contexts. So if you are offering Ogg, you have to offer it as a second choice after MP4, because the Ogg is only going to be needed a small minority of the time.

回答3:

It doesn't appear to to support raw MIDI files, in Chrome 10 at least.

However, the W3C says it supports XMF which can have MIDI embedded. Not sure about browser support though.

回答4:

Browsers are not required to support any specific codecs or encodings by the HTML5 spec. There is some discussion around supporting MIDI-like sound behaviour in the future, but not much - these two posts on the mailing list last year didn't get any direct responses.

I know that QuickTime does (or used to?) support MIDI, and Safari will play any audio that QuickTime supports, so it may work already in Safari but I haven't tried it.

回答5:

To quote from the official Web MIDI API page (http://www.w3.org/TR/webmidi):

To some users, "MIDI" has become synonymous with Standard MIDI Files and General MIDI. That is not the intent of this API; the use case of simply playing back a .SMF file is not within the purview of this specification (it could be considered a different format to be supported by the HTML5 <audio> element, for example).

In other words, W3 Org says browser support for simple MIDI files should be through the HTML5 tag. Sadly, as far as I know, no browser yet supports MIDI via the <audio> tg. But I'll bet that the first one which does is going to get a huge chunk of market share. For example, the site at http://www.hymntime.com/tch has thousands of MIDI files that still have to use the old <object> tag to play. And even then, it still requires a plugin. Try explaining to a non-technical user what a "plugin" is or how to install one!