Commercial Detection

[colin]

Starting a developers thread based upon:

Commerical Dectection - wishlist thread

Cheers,
Colin.
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Edit ---> last version For Jere_Jone's reasons, go to page 17 <---

Thanks Jere for all your work - it was and is appreciated

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See page 16 for more info, or follow the link.

Edit - pointer to latest comskip --> 0.60 <--

[CodeMonkey]

We can either always store I frames in the cut file (somehow?), or worst case you skip to the next I frame from our cut point. A couple frames won't make any difference I wouldn't think.

[colin]

Assuming we can detect the frame accurate commercial start/end points, then maybe we should also provide the nearest I-frame start/end point as well.

So if you want the remix plugin to use the cut points, it can use frame accurate points, or nearest the mark points.

Colin.

[windsorguy13]

This is a stupid aside, but figured I'd mention this as well. With the Myth project there was concern over the legality of the commercial detection scheme and skipping comercials. As this functionality was built into Tivo, the Tivo company was pursuing legal action against a different PVR software group for providing commercial detection/skipping. It never spilled over to Myth (yet), but I figured I might post this info ...
BTW, can't wait for commercial detection in GB-PVR    !!!!!

Thanks,
Brian

[CodeMonkey]

Tivo wasn't the first to do that. I remember a gadget several years ago that worked with a VCR and stored the cut points right on the tape so it could fast forward the vcr past those points. Certainly even in this lawsuit happy age that simple idea can't be patented. At least lets hope there is some sanity left in the legal system.

[Jesse]

Guys, food for thought:

I think it would be quite preferable to be able to filter commercials during the recording phase. It would have the potential to shrink the size of recorded programs by 25-33%, which in the long run would be huge. I believe this should be a checkbox for each individual recording.

Also, I'm pretty excited about this project, and would like to get involved if I could. I'm a pretty technical guy with some programming background.. Is there anything I can help out with? Besides the wishlist I've posted, and some major instability with my MVP, commercial skipping is my most wanted feature.

Do you guys have a start on this plugin, or should I start from scratch?

[colin]

Hey Jesse,

it really hasn't got too far off the ground yet. as you say ideally this would be best done at recording time which would mean Sub would have to do it.

The advantage is smaller mpeg's, the disadvantage is if the commercial detection gets it wrong.

the alternative is a plugin which could at least run against the mpeg and give a set of cut points.

The advantage is if the cut points are wrong, then you do not loose anything in the mpeg, but the disadvantage is its a post recording operation.

I have the src for Cutterman (its open source) if anyone wants to have a look at it. Its written in C# and may assist in analysing an mpeg stream. Cutterman needs the stream to be demuxed as it can only handle video. Ideally we would want to read a muxed mpeg to save time.

Of course, all suggestions are welcome

Colin.

[sub]

I must admit, I prefer the post processing option.

None the products that do commercial detection seem to get it right all the time. Its more like 90%. To have it automatically apply this at recording time implies you are going to loose video video that you ultimately want to see.

Doing it at record time also means you need to decode the stream in realtime as you record so that you can search for the usual signs of a commerical (black frames etc). In effect, you'd loose the low CPU advantage you get from using hardware MPEG-2 encoder cards.

[colin]

Plus I think doing this as a plugin would be a good fun

[jorm]

have you guys started any development of this plugin?