[mythtv] ATSC question

Dan Wilga mythtv-dev2 at dwilga-linux1.amherst.edu
Wed Feb 24 17:06:58 UTC 2010

On 2/24/10 10:04 AM, Devin Heitmueller wrote:
> On Wed, Feb 24, 2010 at 9:24 AM, Dan Wilga
> <mythtv-dev2 at dwilga-linux1.amherst.edu>  wrote:
>> It would be useful if there was some way that this could be used to know
>> when a particular program (like a sports event) is running late.
>> So if I have "60 Minutes" scheduled to record, but it's delayed due to
>> football beforehand, the proper data isn't sent in the stream to indicate a
>> new program starting. So keep extending the end time of the recording until
>> it is seen.
>> This could even be useful for those annoying cases where networks
>> intentionally skew start/end times by several minutes in a vain attempt to
>> keep their audience captive. Basically, don't stop a recording until the
>> next program starts.
> Yup, all that would be great.  Except the broadcasters don't actually
> do that.  They populate the PSIP feed pretty much with the same data
> that is used by SchedulesDirect.  In other words, if a program runs
> long, then the ATSC guide will be just as screwed up as the
> SchedulesDirect guide.
> Unfortunately, the broadcasters don't really have much incentive to
> make this system work well, and in fact they probably wouldn't have
> done it at all if they hadn't been compelled by the FCC (their digital
> carriage license requires it).

I'm not referring to the scheduling data, which I agree is flawed.

Perhaps I misread something, but I thought one of the previous posts 
implied that there is a change in the data when a program actually 
starts, for V-CHIP purposes. I assume that the broadcasters don't 
automatically say, "just because it's 7:00 PM on Sunday I'm going to 
send out the V-CHIP data for 60 Minutes," whether it's on or not. I 
assume they only send the data when the program actually starts. 
Otherwise, V-CHIP wouldn't really be doing what's it's supposed to do.

Of course, all of this is just an assumption based upon what makes 
sense, and with complete ignorance of what really happens, or the 
protocol being discussed. So it's pretty likely I'm wrong :-).
Dan Wilga                                                        "Ook."

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