[mythtv-users] Daddy, what's a commercial

Brian Wood beww at beww.org
Fri Jan 12 20:18:45 UTC 2007

On Jan 12, 2007, at 1:08 PM, Michael Lynch wrote:

>> I do wonder if the audio should be taken into account as well as the
>> video. If there were some way to measure the "density" of the audio
>> it would almost certainly be found to be higher on commercials.
> Granted it's been mentioned before (by me and another person I think),
> but couldn't commercial detection be enhanced using the VBI data and
> finding the program rating?  Judging from another thread today about
> 'parental blocks', commercials do not have ratings and could possibly
> open up another door for detection.  This is all assuming that the
> rating isn't carried over into the commercial from the program...

Good point, and there is other information in the VBI (or its digital  
equivalent) in addition to the rating info, such as closed- 
captioning. A lot of commercials, even those that are not captioned,  
issue a "clear" command at the start to make sure there is no garbage  
on-screen left over from the program or preceding commercial. That  
would help in identifying "blocks", even if it didn't help in  
deciding if that "block" was a commercial. For example a block that  
was exactly 30 seconds long would have a higher "score" if it started  
with a clearCC signal.

But as I said, even using these techniques would only improve things  
by a small increment at best, and I don't think we will ever get to  
100% effectiveness, even without "countermeasures" from the  
broadcasters and advertisers.

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