[vorbis] .ogg file extension for both audio and video?

[Nathan I. Sharfi]

On Fri, 4 Jul 2003, SwiftBiscuit wrote:

> --- noprivacy at earthlink.net wrote:
> > Microsoft had the same problem with their old ASF
> > extension.
> > That's why they changed it to wmv and wma.  Same
> > file format, just a different extension so people &
> > apps can easily tell them apart.

(snip)

> > Even Microsoft isn't completely stupid.
> Really? They created this mess in the first place by
> making the whole thing revolve around extensions.

And yet, extensions simplify. Consider an extensionless universe where
you're trying to encode to Vorbis from a RIFF WAVE; you'd have to do some
needless acrobatics to make sure that the filenames don't clash. Options:
 - Rename in encoding, either by adding metadata into the filename (and
generate, say, "02. Cheeseburger in Paradise" from "02 - Cheeseburger in
Paradise".
 - Move on encoding, much like flac's --output-prefix when used with
directories.
 - Recreate extensions with "02. Cheeseburger in Paradise (Vorbis)".

<div style='voice-family: "Doomsday Prophet", male'>
 The time of extension clashes is upon us! Repent now!
</div>

I've heard that there's some push, somewhere, to move the default container
format for FLAC to Ogg. This might just be Jack's random rants.
Anyhow, having both just application/ogg and a 1:1 mapping between file
extensions and mimetypes will lead to extension clashes which can be solved
relatively simply with one extension per type of file. I've suggested
application/x-vorbis+ogg, application/x-flac+ogg, and
application/x-speex+ogg (like application/xhtml+xml on
http://www.w3.org/TR/xhtml-media-types/#application-xhtml-xml).

I've heard quite a few complaints that this is a hack of the MIME type
system; I point out that MIME is already incapable of mapping out everything
about a file that is of importance. However, by drawing the line of what is
mapped further in by including the contained formats in the mimetype, we can
have a 1:1 mapping between extensions and mimetypes (not something I
particularly care about, but a valuable nicety for some) and enough
extensions to keep files from stomping over each other when transcoding,
muxing, and demuxing.

So, in summary: extensions aren't that evil.

Nathan
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