Dealing with bright lighting at competitions and vision

[Thardro]

This weekend we competed at the North Star regional and will be progressing onwards to Championship. However, throughout the regional we struggled to get vision tracking on the tower working due to other lighting at the event reflecting off of the tower and conflicting with our green LEDs despite tweaking of our HSV filter. Currently we are running an HSV filter on the image from our camera and then comparing the area of each particle found by NIVision to the area of the convex hull to eliminate solid lights found in the background. Is there anything that we could do to improve our recognition, especially for under the lighting at Championship?

[Ozuru]

Your flaw is relying upon a HSV filter (and only a HSV filter) for identification of your target. That's like saying any orange car is a Dodge Charger. What are some ways you can verify that it is actually a target?

[Thardro]

Originally Posted by Ozuru

Your flaw is relying upon a HSV filter (and only a HSV filter) for identification of your target. That's like saying any orange car is a Dodge Charger. What are some ways you can verify that it is actually a target?

As I said in my post, we are also comparing convex area to the area of the particle found by the filter. I also forgot to mention that we have tried checking how close the particle is to a trapezoid along with checking the aspect ratio. Our main problem is that even with our LED ring the lighting at the competition can overpower our LED, causing no green light to be visible in our images.

[adciv]

Based on past experience, I recommend using Purple. There's too much green/red/blue at competitions and around towers.

[RufflesRidge]

Originally Posted by Thardro

Our main problem is that even with our LED ring the lighting at the competition can overpower our LED, causing no green light to be visible in our images.

Sounds like you need to lower the exposure and/or brightness on your camera or put a filter (some teams ave used sunglasses in a pinch) in front of it.

[Thardro]

Originally Posted by RufflesRidge

Sounds like you need to lower the exposure and/or brightness on your camera or put a filter (some teams ave used sunglasses in a pinch) in front of it.

Other than sunglasses, what would you recommend to use as a filter? Should it be a particular color?

[RufflesRidge]

Originally Posted by Thardro

Other than sunglasses, what would you recommend to use as a filter? Should it be a particular color?

A "neutral density filter" would be the correct thing to reduce light entering the camera without modifying hue.

[Greg McKaskle]

If you have an image, that would go a long way towards being able to make a good suggestion.

The LV example uses aspect ration, moment of inertia, area/convext hull area, and an X and Y profile mask. None of these are expensive to calculate, and all of them help to compare analytical values of the U shape that is expected versus the computed values in your image.

Greg McKaskle

[electroken]

Originally Posted by adciv

Based on past experience, I recommend using Purple. There's too much green/red/blue at competitions and around towers.

Exactly why we're using orange.

[Owen Busler]

Team 303 had a similar issue at our competition last week. Im not convinced its the best way to solve this problem but we just added more and brighter green leds until it overpowered the reflection off the glass. In the end we had three of these rings concentric of each other.

https://www.superbrightleds.com/more...ghts-cob/1135/

They really are super bright, its pretty crazy. We also had a paper cup with white gaff tape on the inside to direct the green light. I couldn't find a good picture. Here is the best I could do:

https://goo.gl/photos/b7osRmTW6Vbs7uaZ9

[Thardro]

Originally Posted by Greg McKaskle

If you have an image, that would go a long way towards being able to make a good suggestion.

The LV example uses aspect ration, moment of inertia, area/convext hull area, and an X and Y profile mask. None of these are expensive to calculate, and all of them help to compare analytical values of the U shape that is expected versus the computed values in your image.

Greg McKaskle

Here are a few images from on the field. Our two main issues were from cases like these two perspectives where lighting reflecting off of the tower would merge with or overpower the reflection from the LEDs or the reflection from the LEDs would not be different enough from the surrounding tower to be distinguishable using HSV values.

[jdesmond]

Originally Posted by Thardro

Other than sunglasses, what would you recommend to use as a filter? Should it be a particular color?

You can program an exposure value, how do you implement your camera and vision processing?

[Eric Scheuing]

Originally Posted by electroken

Exactly why we're using orange.

It also happens to match your color scheme!

[bigbeezy]

We use IR LEDs, an Axis camera, and a strip of developed film to cover the lens. Works great. All the camera sees is the IR reflection. Midwest had a banner running right behind the goals that could have washed out some other methods. Our camera couldn't even see it.

[jweston]

I believe you are allowed access to the playing field on day zero for camera calibration. At least, that's what we're doing. We use the green light ring too and I've seen camera calibration be the difference between silver tape and green tape in the image. Changing the camera settings for the field should make a huge difference if your image filtering is working fine at your practice field/workshop/etc.