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I make comedy shows about maths with Helen Arney and Steve mold as
Festival of the spoken nerd. Our most recent show is out now on DVD.
The others like to do their music and science things, but I like to stick to actual maths.
To celebrate the release of the DVD
I'm sharing a section of the show here on
YouTube where I help edit live footage using projections outside of a sphere
Now if like me you are of the mathematical persuasion you may occasionally be accused of
not being useful
Apparently just proving that theoretically everything will arrange in 3d space to fit does not count as putting on the dishwasher
However recently
I had an opportunity to use my maths for good when I came across this
cutting edge piece of
Technology, and a lot of people believe that being a nerd is all about having the latest bit of tech and that is true
But the extreme version of that is when the tech is so new. You have to use some maths to write the software yourself
Anyone who uses Linux will know the giddy thrill when you buy something and it's so new you have to write the drivers yourself
Okay fewer than I expected, that's fine.
Oh if you don't know what Linux is, Linux is a bit like
punching yourself in the face
When someone says "Why are you punching yourself in the face", you go
"Oh it's free"
Thank you
A little too close to home, huh?
Okay, so what this actually is it's something called a spherical camera
You'll often see these marketed as being a
360-degree camera, which is a shame because that's incorrect
Right because 360 degrees of freedom when filming would just mean you can go around like this but not up and down as well
360-degree footage would be like the world's worst widescreen like that
360 footage this is spherical footage and the way it does it is by using two
Fisheye lenses, which if the software works we can get the live feed from up on the screen come
Yes, okay so far so good. You can see one lens is facing me. You can see me over here
The other lens is facing the guys over there so you can see them on the far side of the stage and there's enough overlap
That the computer can stitch them together into a complete
Spherical view in every single direction at the same time
So normally when you take a photograph, you can only look in the original direction the photograph was facing in this case
You can grab a mouse and you can just grab the footage and drag it around wherever you want
Right, you can bring an end over here. You can see. Oh there's you guys loving the show as I can tell
Thank you for waving just to convince yourself. It's not fake
Which would have taken more effort
Will oh, by the way, this is what it would look like if I get this just right. Here we go
This is what it would look like if you were in the audience watching the show right now
Modern technology
And oh you may have noticed are the one downside to this is when we put it together
It flips the footage. So in reality, I'm on you're right
But the first Matt down, the one pointing at the next one down
Is on the left and then on the right and then on the left and originally this was a bug
Until we declared it a feature
Because watch this. Watch what happens when I walk between it.
Wait for all the Matts to get involved
More dancing than I was expecting to do
Okay, so, all right
so we got this all up and running and I keep saying we because I went to a
Mathematical friend of mine a guy could Henry Segerman who's an expert in spherical geometry
I was like, come on there must be some amazing maths we can do
Using the sphere of footage which comes off one of these cameras
And he was like, "Well you can, except, you
don't get it as a sphere." Because it's footage
it's got to come as a on a flat surface, right, as if it's like normal video.
And so what actually comes off the camera is called rectilinear footage
This is what you actually get through the feed and this is not reality anymore
We've broken it in a couple ways for a start there's now an edge so you can see like here somewhere
I look at Matt up there there's the edge to reality. So if I go like
That's not normal
It also ruins like the top and like that's a mess
What's going on around there?
if if I move my arm around at some point it's going to detach from my body and fly across it's not
It's not good
And we forget how bad this is because our normal projection of the earth is the same rectilinear
projection and only works in the middle
It gets distorted and changes shape the further out you go
But we see it so often we forget how terrible that is a much better way of doing it would be a projection like this
So here I have the spherical earth we all live on, and underneath it's perfectly projected onto a flat surface
Down the bottom here is the flat world
We all live on and this is what it would look like if it was perfectly projected up onto a sphere
It's the controversy
Well, this is done is actually it takes a vector from the North Pole
Extends it down through the sphere
and then wherever the pixel that goes through the sphere on hits the plane it projects it down there what it means is you've no
Longer got any edges and you don't get any weird
distortions and so then who took all of this from Henry and I took I went to another guy called Aaron Montague an expert in
live mathematical visualization I was like
Right. Can we take the feed from the camera and do that live, and unbelievably Aaron got it working
so this is the live sphere of footage coming off the camera right now and
Underneath it. Is it being projected down onto the plane? And so there's no longer any edges
I can come underneath the camera and that's all still fine
I mean the North Pole is still a bit distorted, but very consistently so we can do some very interesting maths with this
So I was like what we gonna do
Henry's like well now we've got this projection working with the camera we can take
Reality, and we can copy and paste it
I've always wanted to copy and paste reality. I mean, I'll be honest my top request would have been undo but
I'll take copy and paste
So now if we get this is just a fixed view
directly overhead onto the stage and you can see there's one mat up on the stage and occasionally you watch the show and you're like
"Man, I wish there were more Matts." Well now two Matts. Loot at that
So there's now two mats two audiences two screens. I can chase myself around the stone get back here you
Can indulge your little self high five.
You can have a lot of fun with this
It does cause a few weird side effects actually a few folks wouldn't mind giving me a hand
I've brought with me some footballs here. So I'll give you one
Hellen, Steve, you take one. If they throw these backwards and forwards in front of the camera
It's not that hard. Here we go.
Well, you're making it look hard.
Okay, now now all the spontaneity is out of it
You can see in reality. They're throwing the balls directly backwards and forwards in front of the camera. Up on the screen
however, there are now two of each ball two of each person and it's perfectly's not perfectly joint
Okay, so let's try let's try some juggling so actually if we give Steve I've got some juggling balls here, huh?
Would you mind juggling around the camera? I'll go back down to a single Steve. So if Steve juggles, I figure
Wow look at that happy face
If this is the biggest laugh we get all night you're in so much trouble
This Steve is juggling by himself
If we now go up to two Steves you can see the juggling tricks are now between the Steves
So each trick is one left hand and one right-
I don't know what to wipe it with
It's your camera as well if you want it now
Okay, let's go down to a single Helen my goodness okay
Okay, if we can get to six Helens you burst into applause. We all move on together. Okay, here we go. So one Helen
So far so good
Two helens
Look at that concentration
Three Helens.
More Helens
(Helen): This is quite stressful now
Get them try again
It's your time you're wasting
We're going back down to three as a penalty. Okay, here we go. Three Helens
Now we've now got four Helens
Great response, five Helens
AND SIX! Six Helens!
To watch the rest of the show grab a copy of the DVD or you can download it from all the usual places
Link in their description. Oh and you can also get the show on floppy disk because Helen thinks she's hilarious
To watch some more of the show for free head over to Steve's channel where he's also put a section online
(Steve): To celebrate the release of the DVD
I'm sharing a section of the show here on YouTube where I help win an argument using temperature outside an aeroplane
(Both) So do watch (Matt's/Seve's) video and if you can afford it we would love you to buy show. The download is just π pounds
Or even less if you're a patreon supporter.