Re: MPEG asks for MIME review for the MPEG21 file format

Hello Dave,

Some very good questions.

At 00:27 07/05/19, Dave Singer wrote:
>For a lot of these encodings, of course, the initial string is identical (all the ones which have an 'ascii'
core).  UTF-16 uses twice the bytes etc.
>
>But in general, given a MIME type with a "+xml" suffix, an XML reader should be prepared to do what?

At the minimum, handle it if it's UTF-8 or UTF-16 (with BOM in the later
case). Everything else is optional.

>I think I am reading "treat the resource as being, in turn, all the encodings you know of, and if you treat it
as an encoding, do you find a confirming "encoding" attribute?"

My reading of Appendix F of the XML Spec would be somewhat different.
(See http://www.w3.org/TR/REC-xml/#sec-guessing-no-ext-info.)
First, it's not character encodings, but character encoding families,
that you try. This makes this process quite a bit faster.

Second, that appendix gives a list of character encoding families.
As the appendix is non-normative, it doesn't necessary exclude
other character encoding families, but there aren't really any other
character encoding families that I know of.

>Which means that encoding='EBCDIC' (I made that up, by the way) would work?

You didn't have to make that up. EBCDIC as a family is listed in said