Do you need the exposure values?

[Code\\Pilot]

So, my GUI somehow doesn't work, so i used the hyperterminal to calibrate the cam. The values i got from the gui where the RGB maximum and minimum values for wichever color i wan to track. Let's i want to track for green, so i run the GUI, capture the frame, and roll my mouse around the green target to find the max and min values that i would plug-in on the code. I notice in the code there is this line that says:
camera_init(exposure whatever blah blah) do i need these exposure values? if i do, how do i find them without the GUI?

[Code\\Pilot]

would any one answer, :'(???? please????

[Mike]

You need those numbers, but I don't know how to get them without the GUI.

[neilsonster]

For some reason the default exposure values seem to be perfect for our school... Luckily we are being given the "official" values at each competition's building, so you really only need to get new ones if you are having trouble tracking with your own lights.

[Greg Marra]

Originally Posted by MikeWasHere05

You need those numbers, but I don't know how to get them without the GUI.

Why do we need those numbers. Can anyone explain to me what CR 19 (the camera register that I believe those numbers are inserted into) does?

It seems to me that "track green" in the GUI almost always works under any lighting conditions, regardless of whether I have calibrated yet or not.

And if anyone knows the commands that "track green" in the GUI sends to the camera, I'd be extremely interested in knowing.

[Greg Marra]

Originally Posted by Greg Marra

Why do we need those numbers. Can anyone explain to me what CR 19 (the camera register that I believe those numbers are inserted into) does?

It seems to me that "track green" in the GUI almost always works under any lighting conditions, regardless of whether I have calibrated yet or not.

And if anyone knows the commands that "track green" in the GUI sends to the camera, I'd be extremely interested in knowing.

And lo and behold, I have answered my own questions.

"What does 'Track Green' do?"
For the answer to this question, see "CMUcam2GUI_fe\src\config.txt"

"What is CR 19?"

CR 19 sets the camera's internal auto-exposure control level. 0 would create a totally black image. 255 should create a totally white image. The key is keep the image dark enough that bright areas (like what we're trying to track) don't get drowned our by background noise. Basically you want this number to be as low as possible without totally blacking out your image. What the specialized FIRST GUI does is calculate this number for you, saving you a lot of work. I speculate that the progress bar indicates how far it is (0-255) and that the reason why it often doesn't finish is the calibration value is below 255.


Now here's the really big question:

How much variation is there in color detection from unit to unit, and can I trust the numbers first gives me?