Quoting David Henningsson <address@hidden>:
I think it might be best to just query libsndfile for the first
supported audio format, for a given file type, if no audio format is
specified and the default of 16 bit PCM fails. That would solve the
Ogg/Vorbis issue and possibly work fine with future supported file
types which have a specific audio format.
If that is possible, that would be even better.
With sf_command you can query the available audio formats for a
particular file type. If they add support for other audio formats to
Ogg though, that could become a problem, since you wouldn't be able to
specify Vorbis explicitly in that case.
Another option would be to dynamically list all the available formats
(by querying libsndfile for their descriptions) and for formats that we
know of, provide a short abbreviation as we do now. For unrecognized
formats, it could just list something like fmt17 (using its assigned ID
number). Whenever "fmt" is encountered, whatever number follows would
be used verbatim as the format ID, so that any format could be specified
by its number (to provide backwards compatibility in future versions
where we add a format abbreviation).
I think I might like that the best. We could also make it to where -O
help would list only valid audio formats for the given file type (if
specified).
How does that sound?