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Follow-up questions for details on the "min distance" algorithm

From: Peter Thatcher <pthatcher@google.com>
Date: Tue, 5 Aug 2014 09:46:07 -0700
Message-ID: <CAJrXDUGRK+6-1uoQQZ0rFQ1+aatgvJiq1paUFZEOVRRumAqFAA@mail.gmail.com>
To: "public-media-capture@w3.org" <public-media-capture@w3.org>
We reached a rough consensus on pursing "min distance" in general, but
there are still a few details we need to decide on:

1. Harald proposed putting in the text something like "behave as
though this were the algorithm: ...", to make it clear that the
implementation doesn't have to implement it exactly like that,
especially when dealing with cameras that have ranges rather than a
set number of modes.  Is that OK with everyone?

2.  Someone (I think Martin) suggested we not give framerate special
treatment for being greater than the ideal, and make it behave the
same as width, height, and aspect ratio.  I'm fine with that.  We can
just remove the "CLOSE_OR_GREATER" bucket.   Should we go ahead with
that?

3.  What do we do with ideal values <= 0?  For all the constraints we
have so far, I think it would be easiest to just reject them with an
error.  Would that be OK?

4.  When we want a "strong match", such as for sourceId, what should
the value be?  1000000?  "Infinity" has problems.  We really just need
a "big value".  Is that a "big value" good enough?

5.  Some changes to the min distance calculation were suggested, such
as squaring values.  If you have any, please try it out by forking
this spreadsheet:
https://docs.google.com/spreadsheets/d/1amhQGmxq5TeE7R510HXKhqFpc_fU6oiTaGGO7pF_DKg/edit#gid=0
and applying it to some examples.  If the results look good, please
let us know the formula change you would suggest.

Thanks for your feedback,
Peter
Received on Tuesday, 5 August 2014 16:47:13 UTC

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