Mailing List Archive

Chris Pinkham wrote on Mon August 11, at 23:56 -0400:
> > > manually (if Q doesn't take me back to where I was). I wonder whether
> > > it would be sensible to have an upper limit for skip - say about 300
> > > seconds (commercials don't usually last longer than that).
> >
> > Uh huh. What planet are you watching TV on? I might wanna join you. :)
> > Here on mine, late nite TV often goes over five minute commercial breaks
> > in the back half of a movie. Better up that to seven or eight minutes.
>
> The blank-frame detection code that is used during the auto-flagging thread
> does not have a max. It just keeps checking for what it thinks are
> commercials and flags all of them. The on-the-fly blank frame detection
> code has a 300 second limit on the commercial length.

I must admit I'm confused about the differences. I couldn't find any
docs, so I was just blindly playing with the settings. Just read
the source now, which makes things a bit clearer.

Is there a way to do the on-the-fly stuff without automatically
skipping?

,dunc

> > The blank-frame detection code that is used during the auto-flagging thread
> > does not have a max. It just keeps checking for what it thinks are
> > commercials and flags all of them. The on-the-fly blank frame detection
> > code has a 300 second limit on the commercial length.
>
> I must admit I'm confused about the differences. I couldn't find any
> docs, so I was just blindly playing with the settings. Just read
> the source now, which makes things a bit clearer.

I hate writing docs. :)

> Is there a way to do the on-the-fly stuff without automatically
> skipping?

Auto-skipping is disabled if you don't use the auto-flagging option
in current CVS. The on-the-fly detection is nowhere near as accurate
as the auto-flagging thread and I hasn't been worked on in quite a while.
If you are using software-encoding, then blank frames are always detected
at record-time whether you have auto-flagging turned on or off. When you
turn on auto-flagging, the code will fire off a commercial flagging thread
after a recording finishes. This code is better than the detection done
at record-time and is necessary for good detection when using hardware
encoders.

--

Chris

Chris Pinkham wrote on Tue August 12, at 17:57 -0400:
> I hate writing docs. :)

Fair enough. So do I :-)

> > Is there a way to do the on-the-fly stuff without automatically
> > skipping?
>
> Auto-skipping is disabled if you don't use the auto-flagging option
> in current CVS. The on-the-fly detection is nowhere near as accurate
> as the auto-flagging thread and I hasn't been worked on in quite a while.
> If you are using software-encoding, then blank frames are always detected
> at record-time whether you have auto-flagging turned on or off. When you
> turn on auto-flagging, the code will fire off a commercial flagging thread
> after a recording finishes. This code is better than the detection done
> at record-time and is necessary for good detection when using hardware
> encoders.

Thankyou!

I was also confused by the following comment:

setLabel("Commercial Skip Method");
addSelection("Blank Frame Detection (default)", "1");
addSelection("Blank Frame + Scene Change Detection", "3");
addSelection("Scene Change Detection", "2");
setHelpText("This determines the method used by MythTV to detect "
"when commercials start and end. You must have "
"automatic commercial turned on to use anything "
"other than 'Blank Frame'." );

I didn't know whether that meant the auto-flagging, or the auto-skipping
option.

I experimented last night and had better results with blank frame over
blank+scene. Turned auto-skipping on for a lark and actually had it
skip properly a couple of times - much fun!

,dunc