On Thursday 20 October 2005 11:03, Rudy Zijlstra wrote: > Daniel Kristjansson wrote: > >On Thu, 2005-10-20 at 09:57 -0400, Steve Adeff wrote: > >>On Thursday 20 October 2005 09:25, Ivor Hewitt wrote: > >>>Daniel Kristjansson wrote: > >>>>DVB/ATSC time can never be as accurate as ntpd time because the > >>>>transmission, buffering, and capture delays can not be measured. > >>>>But it should always be within a few seconds of the correct time, > >>>>so it is more than good enough for a MythTV backend. > >>> > >>>Actually you might say for mythbackend purposes it might be more > >>>accurate, since it's the current time that should match the start times > >>>of programs accurately.... even if it is delayed slightly. > >> > >>is this why so many shows don't start "on time"? If the TV stations > >> follow their own time code then it would make more sense for mythbackend > >> to run on this time. I guess the only issue is if two stations are > >> running on their own, differing time...? > > > >In the US companies using the public airwaves are supposed to use GPS > >to set their clocks, so a program should always start a little late, > >and never early. This regulation doesn't apply to cable, and I don't > >know what the laws are in DVB countries. But this is what pre-roll > >and post-roll are for. If you add 5 seconds on each end you should get > >the entirety of any program when you don't have a recording scheduled > >before or after the program, at that point MythTV ignores the pre-roll > >and post-roll settings on the assumption that you would rather get the > >other program than apply this extra safety buffer. > > > >There is some controversy over whether MythTV should have a pre-roll > >and post-roll which is never ignored. But this is mostly due to > >channels in Australia which don't adhere to their published schedule > >and air programs up to 20 minutes later than scheduled. This would > >be illegal in the other countries unless they transmitted updated > >EIT data or the government activated some sort of emergency broadcast > >override, say in the case of global thermonuclear war. > > > >-- Daniel > > In the Netherlands, Belgium, France, Germany - those i am certain of - > programs can start more than 20 minutes later than announced. Not on all > channels, some are worse than others, yet most channels are "late" by > 23:00 or later. Which is why i am using a hard "end-late" setting on all > recordings, and enough tuners so that recordings do not need to be > back-to-back on the same tuner. > > It does not matter whether the broadcast is analog or digital (DVB), the > behaviour is the same. And EIT-schedule, even EIT-next/now is not always > modified.... > > Cheers, > > Rudy
wow, thats so weird. why do they do this? _______________________________________________ mythtv-dev mailing list mythtv-dev@mythtv.org http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-dev