Technology in the olimpic's swimming pool

Ivan Speilberg · Post by **Ivan Speilberg** » Sat Aug 21, 2004 7:34 am

Does somebody know EXACTLY how they "project" the athlethe's flag and name in each lane in the pool??? The NFL, ESPN, ect. also use this technology to project a red line in football games (to mark the ball's possition at each play)

I noticed that there are some black "dots" all allong the center and corner lanes in the bottom of the pool. This made me think that they might be reference points for the "motion tracking camera" that they might be using. My theory is that they use a special software that uses the reference points to determine the camera's movements and then uses that info. to correctly place the graphics in each lane.

If you watch the swimming events on the olimpics you will know what I'm talking about. Any info. on EXACTLY how they do this???????????????????

U.S.Amateurfilmaker · Post by **U.S.Amateurfilmaker** » Sat Aug 21, 2004 8:33 am

I'm thinking that they get word of the exact cam position ahead of time, so all they do is prepare the markings to match the footage that will be streaming in, and then they composite it over in real time. Just my opinion, but I have no idea of the real method. But I have wondered about that for a long time as well

Ivan Speilberg · Post by **Ivan Speilberg** » Sat Aug 21, 2004 8:49 am

I'm thinking that they get word of the exact cam position ahead of time

I don't think soo because I once saw the cam wabble a bit and the graphics stayed correctly between the lanes (the graphics moved allong with the lanes, like if they were attached to the water)

I'm veeeeery good "figureing" (spelling?) out sfx, but I can't figure out this one .....

HELP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Syras · Post by **Syras** » Sat Aug 21, 2004 9:10 am

it would be a realtime motion tracking system linked to a realtime compositing system, similar to the setup they use to do the weather behind the presenter (and yes i know this is blue screening, but if u've ever seen a realtime keying system they look similar to the tracking systems)

Epsilon · Post by **Epsilon** » Sat Aug 21, 2004 9:45 am

Same with the football games where the display the lines over the field. It's just a real-time tracking like Syras said and they can place whatever they want wherever they want on that virtual field. You can tell its a color screen because sometimes if the players are wearing green they get keyed out for the line, which is funny.

Raptor · Post by **Raptor** » Sun Aug 22, 2004 2:06 pm

http://entertainment.howstuffworks.com/ ... n-line.htm

Epsilon · Post by **Epsilon** » Sun Aug 22, 2004 6:27 pm

Hey, pretty cool link, Raptor.

El Brenty · Post by **El Brenty** » Tue Aug 24, 2004 2:01 pm

By the way, this is the first time that cameras have been used under water for the Olympics, and one of our swimmers cut her leg on the camera when she dived in to do some practise.

reflexive_cinematics · Tue Aug 24, 2004 9:58 pm

i've wanted to know how that was done forever now... Thanks RAPTOR!

2nd_Recon · Post by **2nd_Recon** » Wed Aug 25, 2004 12:22 am

If what you're talking about is the flag and then the countrys name that shows up when the first swimmer touches the wall, that is a set of tiles that flip over when a pressure sensitive patch on the side of the pool is hit, (As in, from a swimmer pushing off it) that flip over and show the flag.

Epsilon · Post by **Epsilon** » Wed Aug 25, 2004 3:15 am

I don't know what you are talking about! It's all digital.

That's funny though: we go explaining it all out, Raptor puts up one link, and he takes all the credit!

Ivan Speilberg · Post by **Ivan Speilberg** » Mon Sep 13, 2004 7:20 am

that is a set of tiles that flip over when a pressure sensitive patch on the side of the pool is hit, (As in, from a swimmer pushing off it) that flip over and show the flag.

WTF!!!!

How in hell did you came up with that idea???!?!?!?

That kind of technology (flipping dots,tiles etc.) is used in smaller scale, like in public transportation buss's signs and signals. (and it isn't in technicolor, it only uses ONE high visivility color, like safety orange, UV yellow, etc.)

Common sence tells you that if the dark tiles marking the lanes in the pool's bottom become all blurred out when the water gets distressed, that "flipping tile syst." will not work (it will also became blured, like the lane lines)

I noticed that there are some black "dots" all allong the center and corner lanes in the bottom of the pool. This made me think that they might be reference points for the "motion tracking camera" that they might be using. My theory is that they use a special software that uses the reference points to determine the camera's movements and then uses that info. to correctly place the graphics in each lane.

I was pretty shure that they used some king of live tracking system, my theory was right!!!

I WAS SURPRISSED THIS WAS IN THE "howstuffworks.com"PAGE. I'm stuck with that page and it never came to my mind that the EXACT answer might be there!!! , and in fact it was!!

!!!! thanks Epsilon!!!!

PS:

That's funny though: we go explaining it all out, Raptor puts up one link, and he takes all the credit!

That's life..... some times, someone makes all the hard work and then another person comes and gets all the credit !!!

Ivan Speilberg · Post by **Ivan Speilberg** » Mon Sep 13, 2004 7:35 am

By the way, this is the first time that cameras have been used under water for the Olympics

This is the firs time they used a ROBOTIC DOLLY CAMERA underwater. In past olimpics, they got underwater footage taken by divers located at the corners of the pool.

They used a similar camera than the one used in the diving event, the only difference is that this one was horizontally placed and that she had to move by herself, not by gravity. (like in diving)

Where did you heard about the underwater camera accident??? I't a "cool" fact/gossip I haven't heard till' now

!!!

cantoloupe · Post by **cantoloupe** » Mon Sep 13, 2004 9:14 pm

even crasier than the flags, how did they the the views for diving??!! the things where they showed two divers at once, or a diver in all the different positions in one frame?

2nd_Recon · Post by **2nd_Recon** » Wed Sep 15, 2004 3:11 pm

time-lapse?

Ivan Speilberg · Post by **Ivan Speilberg** » Sun Sep 26, 2004 8:46 pm

No. They use a motion controled camera rig. This means that the camera records exactly the same angle of the diver and the panning, zooming, etc. every time "fired". They use a computer to program the motion path of the camera. A motion sensor located in the far back of the diving platform's floor is used to activate the camera, so that she follows the diver in the pre-determined path she has programed.

Later in post, since the camera moves where EXACTLY the same wit ALL divers, they just alter the transparency of one of the 2 layers of divers and the resulting image is 1 diver diving with a "ghost image" of another diver. If you look carefully, you will notice that sometimes in the background there's also "ghost people" . this is caused because either people moved between shots or because they left their original seat.

They use the same technique when they show the same diver repeated all along the screen till' he dives underwater. This is acomplished by useing a motion controled time-lapse camera. All they have to do is splice the ends of one picture with the other in order to create 1 continuous image of the diver in action. This is a technique similar to "bullet time" but with 1-10 cameras only.