Re: SMIL content for specific calendar time ranges

Hi Jack,=0A=0Athank you for your reply.=0A=0A> The slightly longer answer i=
s that it is possible by using a tiny external agent (or script). SMIL Stat=
e (see http://www.w3.org/TR/2008/REC-SMIL3-20081201/smil-state.html) was sp=
ecifically designed with this use in mind (among other things): the whole S=
MIL presentation is declarative, with some parts based on SMIL State variab=
le(s). This variable is then changed by the external agent.=0A> [...]=0A>  =
<state xmlns=3D"">=0A>    <data>=0A>      <year/>=0A>      <month/>=0A>    =
  <day/>=0A>      <weekday/>=0A>      <hour/>=0A>    </data>=0A>  </state>=
=0A> your example B could now be coded as=0A>   <ref expr=3D"weekday=3D7 an=
d hour &gt; 9 and hour &lt; 18" title=3D"specialOverlay"/>=0A=0AThis does i=
ndeed look very promising, I like the flexibility it would imply regarding =
all kinds of complex states we might like to add in the future (which for e=
xample a custom SMIL extension for recurring wallclock event timing would n=
ot give us). Together with the basic SMIL 3.0 Tiny stuff (and possibly Basi=
cTransition) this might just be all we need.=0A=0AWhat I can't gather from =
the SMIL State w3c recommendation, however, is:=0A=0A1) What kind of source=
 file does the "source" attribute of the "state" element expect? Is this co=
mpletely unspecified/client-specific?=0A=0A2) Does any standardization (off=
icial or inofficial) exist regarding how external agents change state varia=
bles of a running SMIL presentation? (e.g. a SOAP schema or something for c=
ommunication between the player and the external agent over HTTP or other m=
eans). How do implementations like GRiNS/ambulant handle this?=0A=0A3) When=
 exacly is the expression in the "expr" attribute of an element evaluated (=
and acted upon)? Only when the element is about to be shown, or is the expr=
ession also recalculated on each state change event? I.e. in the following =
example, will the Happy hour page not only appear when "happyHour" becomes =
true, but also disappear once it becomes false again?=0A<excl duration=3D"i=
ndefinite">=0A    <seq title=3D"Normal presentation" begin=3D"0" repeatCoun=
t=3D"indefinite"> ... </seq>=0A    <ref title=3D"Happy hour page" expr=3D"h=
appyHour"/>=0A</excl>=0A=0A> [...]=0A> Many more wild things are possible w=
ith SMIL State, let me know if you're interested and I can point you to a p=
aper we wrote on the subject.=0A=0AYes, I'm definitely interested :-)=0A=0A=
=0AGreg,=0A=0AOn Fri, May 28, 2010 at 1:44 AM, Herlein Greg <greg_herlein@p=
rn.com> wrote:=0A> PRN uses SMIL for our playlists on our newer generation =
digital signage systems.  We found that wallclock within the SMIL playlist =
was not suitable, partly since we wanted to essentially schedule playlists =
and not have to a) send wholly rebuilt playlists, or b) have to parse a lar=
ge playlist just to get to a portion that applied to a certain day part, an=
d c) we wanted to be able to replace portions of playlists scheduled indepe=
ndently.  We designed a schedule mechanism using XML that is SMIL-like but =
is not SMIL and use that to meet the discrete needs of digital signage.  We=
've share that publically with the POPAI Digital Signage Technical Standard=
s group.  Sanja, contact me directly from your company and I'll see if we c=
an work out a way to share it with you.=0A=0AI've stumbled upon http://www.=
a-smil.org/index.php/Wallclock in the meantime, describing simple "Repeated=
 Date/Time Events" wallclock scheduling for SMIL, specifically intended for=
 digital signage, by allowing "R/.../.." specifiers in wallclock time value=
s. Is your solution also along those lines?=0A=0AWhile this kind of extensi=
on/modification to SMIL would provide support for the case of weekly or sim=
ilarly scheduled items, the State mechanism as pointed out by Jack appears =
to be a much more flexible and probably also cleaner solution at least for =
our purposes, with the added benefit of being officially SMIL compliant, so=
 I'd like to try and pursue that path first. If it doesn't work out, I migh=
t get back to you though.=0A=0A=0A