- From: Yves Lafon <ylafon@w3.org>
- Date: Mon, 2 Feb 2009 10:40:01 -0500 (EST)
- To: public-media-fragment@w3.org
During our last f2f, we discussed the applicability of some units and the
need to create a list for them.
We have two axis, the temporal axis, and the display axis.
The temporal axis is currently debated (see the discussions on the list
regarding seconds (as real numbers) vs frame-oriented units.
For the display axis, we rule out the units relative to the document it
would be displayed in (as the server has no way to know the document the
unit is relative to). So it leaves us with units relative to the
characteristics of the video/image presented:
* Pixels
* percentages (as percentage of width and height)
It would be interesting also to define only one axis (x or y), and define
an aspect ratio, like aspect(16:9), in that case the aspect ratio could
be an relative unit (relative to the other unit in use).
* in, cm when the media gives the information about the relationship
between pixels and in/cm so in general not applicable. Do we want them ?
All other units used in CSS (like pt, pc, em) are dependant on the
definition of pt, and linked in CSS2 to cm/in (as 1pt = 1/72 in), but a
fragment might be applicable to renderer not using this default, so I
would avoid those.
--
Baroula que barouleras, au tiéu toujou t'entourneras.
~~Yves
Received on Monday, 2 February 2009 15:40:14 UTC