RE: [AVT] Draft for new media types (MIME) registration rules

[ned.freed at mrochek.com]

> A few comments on draft-freed-media-type-reg-01.txt:

> <GH1> 4.2.1 Last paragraph:
> This paragraph is a bit strange to me:
> "Beyond plain text, there are many formats for representing what might
>    be known as "rich text".  An interesting characteristic of many such
>    representations is that they are to some extent readable even without
>    the software that interprets them.  It is useful, then, to
>    distinguish them, at the highest level, from such unreadable data as
>    images, audio, or text represented in an unreadable form.  In the
>    absence of appropriate interpretation software, it is reasonable to
>    show subtypes of "text" to the user, while it is not reasonable to do
>    so with most non textual data.  Such formatted textual data should be
>    represented using subtypes of "text". "

> What does it want to say?

This text was very carefully worked out a very long time ago. It has
successfully guided any number of implementations. Unlike most of the material
in this document, I am EXTREMELY reluctant to change it at this late date.

> Is it that there are kinds of text coding expressed in images or on video that are better
> declared as image or video media?

No, of course not. There are, however, numerous textual types that a normal
person cannot make sense of at all without specialized software to interpret
the material.

> E.g. postscript coded text would rather be an image medium?

I have no idea what this means or why it is in any way relevant.

> The thought that text is readable even without the software that interprets it is strange
> and does not produce any distinguishing definition.

On the contrary, it has done exactly that.

> I think encrypted text should still be
> declared as text, but it is impossible to read without interpreting software. So the
> comments rather create confusion than clarification.

This is a red herring. An encryption layer is just that - a separate layer
requiring a separate type declaration. And it is long established practice that
container types belong under application. If necessary an encryption layer can
provide a means of identifying the type or types of the protected content.

> I think that the definition that 4.2.1 starts with is sufficient to define what text is.
> The last paragraph could be limited to:

> "Beyond plain text, there are many formats for representing what might be known as "rich
> text". Coding is often intermixed control information and text contents. Such formatted
> textual data should be represented using subtypes of "text". "

I disagree in the strongest terms possible. This is exactly the text which
various implementations ignored in the early days of MIME, in the
process causing numerous interoperability problems. Removing it now would
be reckless and irresponsible.

> <GH2> 4.2.4 last paragraph:
> "Note that although in general this document strongly discourages the
>    mixing of multiple media in a single body, it is recognized that many
>    so-called video formats include a representation for synchronized
>    audio, and this is explicitly permitted for subtypes of "video"."

> It is also common that text for subtitling is multiplexed into the file or stream. I
> suggest that the word "text" is added so that the paragraph reads:

> "Note that although in general this document strongly discourages the
>    mixing of multiple media in a single body, it is recognized that many
>    so-called video formats include a representation for synchronized
>    audio and text, and this is explicitly permitted for subtypes of "video"."

This is a reasonable change. I'll add it.

				Ned

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