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Re: [MMUSIC] Feedback requested on requirements

worley@ariadne.com (Dale R. Worley) Tue, 23 April 2013 19:06 UTC

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From: worley@ariadne.com
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To: Martin Thomson <martin.thomson@gmail.com>
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Subject: Re: [MMUSIC] Feedback requested on requirements
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> From: Martin Thomson <martin.thomson@gmail.com>
> 
> C3 and C4 look good.
> 
> On 23 April 2013 08:30, Dale R. Worley <worley@ariadne.com> wrote:
> >    non-DES C5  SBCs generally pass through attributes that they do not
> >       understand.  SBCs generally pass through codec specifications that
> >       they do not understand, even if they are configured to transcode
> >       certain specific codecs.
> 
> I'm not sure how to parse this.  Is that a double-negative or just two
> negatives for emphasis?
> 
> Do you intend to say that the solution should NOT rely on new
> attributes because SBCs will suppress them, or that the solution is
> permitted to use new attributes because SBCs are expected to pass
> attributes.

I mean the latter.  The intended parsing is:

    (non-DES) C5  SBCs generally pass through attributes that they do not...

That is, the possible requirements "Use only known attributes." and
"Use only known codecs." are not requirements.

> Non-requirements and non-constraints are always difficult to get right.

There needs to be a word for this...

Dale

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