How the yellow line works

[PatsWickedPissah]

The Mystery of the Yellow Line Video

Interesting for the curious or technically inclined

 

[tanked_as_usual]

I just want to know why RB's keep tripping over the blue line

 

[JSn]

Nice find. Makes you figure it must have required 10x more guys to put tracers on a black hockey puck, hehe.

 

[Fencer]

Good stuff.

A few notes from the video:

How the yellow first-down line on football broadcasts actually works | NetworkWorld.com Community

 

[Pats726]

Always wondered how they did it...really interesting and I agree...a really advanced and good addition...

 

[Willie55]

Always wondered how they did it...really interesting and I agree...a really advanced and good addition...

After watching that, I'm still wondering!

 

[Pujo]

HowStuffWorks did an article a few years ago about it, too. HowStuffWorks "How the First-Down Line Works"

 

[upstater1]

That seems like an incredibly complicated way to do it.

You're telling me they couldn't digitize it by simply having someone behind the ref say, 22 1/2 yard line is the first down. Then just paint a computer generated graphic stripe across the field.

The reason, of course, is that the camera's are not sending the signal back to the truck digitally. It's all still analog, apparently. I'm amazed at that.

If this were all digital, the line would appear no matter the camera angle. It would be based on a simulated model of the entire field, with every angle already pre-programmed for every stadium.

 

[PrairiePat]

You're telling me they couldn't digitize it by simply having someone behind the ref say, 22 1/2 yard line is the first down. Then just paint a computer generated graphic stripe across the field.

The reason, of course, is that the camera's are not sending the signal back to the truck digitally. It's all still analog, apparently. I'm amazed at that.

No, the reason, of course, is that there are players running all over the field obscuring parts of the line in real time. You going to digitize all of them too?

 

[Pujo]

That seems like an incredibly complicated way to do it.

You're telling me they couldn't digitize it by simply having someone behind the ref say, 22 1/2 yard line is the first down. Then just paint a computer generated graphic stripe across the field.

The reason, of course, is that the camera's are not sending the signal back to the truck digitally. It's all still analog, apparently. I'm amazed at that.

If this were all digital, the line would appear no matter the camera angle. It would be based on a simulated model of the entire field, with every angle already pre-programmed for every stadium.

As PrairiePat said, the problem is keeping the line visible above the turf, but below any players that go over it. Just drawing a line at the appropriate orientation would be trivial whether it's a digital or analog system (and where did you get the info that their cameras send an analog feed? I'd be very surprised if that were true, especially with the bandwidth you'd need to send an analog HDTV signal.)

 

[PatsWickedPissah]

The video said that the feed from the camera is over an already existing low bandwidth audio (voice) link that is analog. The analog to digital conversion occurs at the computer. It's obvious that the system is a clever afterthought utilizing stuff that was already there.

Using a low paid television intern to 'mark' the 1st down via human intelligence is far cheaper than the software development testing and calibration of every NFL field in a fully automated system. Too complex a development, debug and test task for the utility. Writing real software is not like in the movies.

 

[Michael]

The Mystery of the Yellow Line Video

Interesting for the curious or technically inclined

I saw an explanation of that a few years ago. On TV. I think that may have been the same video.

 

[Wax Frog]

OK, Pissah, get cracking, link me to explanations of all the other overlays they do now

 

[102 Pat]

Excellent video! I always wondered how it was done. I thought there might of been some kind of sensor in the yard markers...

 

[PatsWickedPissah]

OK, Pissah, get cracking, link me to explanations of all the other overlays they do now

By your command!
I would your Froginess but I'm geting ready to go away for 2 months.
I won't have a PC except for quick peeks at the local library.
Back in March.

 

[Leave No Doubt]

The very first time I saw the yellow line on TV I thought it was real.

 

[Wax Frog]

The very first time I saw the yellow line on TV I thought it was real.

Nah, that was just PWP "firehosing"