[mythtv-users] OT: How is this inline done?

[Mike Hodson]

On Sun, Jan 17, 2016 at 6:00 PM, Jerome Yuzyk <jerome at supernet.ab.ca> wrote:
>
>
> I don't even know how to ask a good Google question for this, and there
> appear to be some broadcast veterans/nerds here, and it's quiet, so I ask.

And I'm glad you did; it allows me to take the time to regurgitate
what I've found out over the years on this subject.

>
> I understand how green-screen works, but there is a new form of inline
> static advertising overlay (or insertion) that I can't understand using
> green-screen. Up here in Canada we get to see ads for Canadian Tire in the
> SuperBowl or MLB (baseball) games, for example.
>


This is decidedly not green-screen; its either camera angle
correlation, or, texture mapping, onto a 3d virtual arena model that
they scanned, likely with LIDAR, to get everything precise.

At first, when I saw the "first and 10 line" on NFL games, I thought
they were doing some very interesting texture-mapping with a computer,
to line up the image in real-time and also to stretch it for
perspective. Nope, the "first and 10 line" overlay image was made
possible by very precise servomotors sensing where the cameras were
pointed, and correlating it in a computer.


>
> It's on the glass behind the goalie nets in NHL games. I first noticed
> Fox-LA doing this a couple years ago in Kings games and now it's come to my
> hometown.

There were a couple of competing firms, but now the leader in this 3d
mapped arena stuff is Sportvision. They even highlight the type of
advertising you mention on the glass backing behind the goals.

http://mentalfloss.com/article/27009/explaining-magic-yellow-first-down-line
https://en.wikipedia.org/wiki/Sportvision
http://ethw.org/Sportvision


>
>
>
> What I can't figure out is what are the overlay/insert "hooks" that one can
> do with glass panels and stanchions? Is there something embedded in the
> glass? The four corners of the ads are on glass, so it's not something the
> stanchions are doing. As for MLB, ads aren't seen in replays, so the ads
> have to be on a separate stream merged into the live feed.

With the increases in CPU horsepower in the recent years since the
simplistic 'first and 10 line', Im almost certain now that they are
using 3d texture maps of the arena and correlating points on their
models with visuals taken by the cameras.  If they're still doing
camera tracking, then perhaps thats just worked for them forever and
they know it well; 3d texture mapping is used in all the post
production stuff now to create convincing, and properly
moving/tracking 3d virtual sets.

Mike