DIY Limelight - Possible?

I wonder that if anyone have tried to make that work on a Raspberry Pi 4.

Before this thread gets any further - posters should recognize the following (it’s been said multiple times now but I think we still need the reminder):

  • Limelight is an off the shelf product
  • DIY Limelight or any other vision processing is just called “vision processing”

Teams have been doing their own vision processing for years. Teams have used a variety of processors to perform their vision processing.

Getting “it to work on a raspberry pi” is getting vision processing working on a raspberry pi, and should not be related to the Limelight.

You will not be able to reproduce the Limelight as it’s custom software and hardware. Nor should you.

Spinning up your own version of vision processing is a great learning tool and a valuable project. Put that on whatever raspberry pi version you want!

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I believe this thread is primarily about creating hardware sufficiently similar to the Limelight that it can run Limelight images.

I guess I am uncomfortable with that intent.

Limelight is copyrighted software and hardware. Since they have not mentioned the license of their code/designs anywhere, I would assume it doesn’t fall under Apache, MIT, etc. licensing schemes.

Therefore modify away - but please don’t share, document, or release your changes. Doing so violates the copyright. Also as @R.C and @Ben_Martin stated above, the limelight team put a lot of time and effort into a great product. Why try and steal their work?

Instead, I think the better option is to discuss the vision methods that the Limelight uses and how to implement such methods on a raspberry pi, or other hardware that people have suggested in this thread.

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Source? I haven’t seen any kind of copyright pertaining to the hardware or software.

All their webpages just say “Copyright © 2019, Limelight for FRC.” Not what license it’s provided under. AFAIK, that means you’re really supposed to assume “all rights reserved.”

There’s also no LICENSE file or similar on any of their GitHub materials.


To bring this thread away from “is putting the Limelight image on a refrigerator legal” and perhaps a bit closer to “building your own vision solution” - OpenSight has just been released. Build your own pipeline in a nice graph UI and it more or less Just Works™, with room for expansion and modification.

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Regardless of official legal restrictions, it wouldn’t be right to just steal a companies hard work and use it in a way it wasn’t intended to be used in, especially since anyone just ripping the software didn’t pay for it.

Now if Brandon and whoever else is involved with the limelight states that they are perfectly fine with people doing this, then go all out. But to my knowledge they have yet to say anything of the sort.

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Copyright indicator is on the bottom of their website:

“Derivative work” - Reason why you can’t create a port of copyrighted code:


Latest and greatest lawsuit about software copyright (and oh boy is this a fun one):

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Good old Oracle v Google. We’ll stop hearing new information about that case right about when the US switches to metric.

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This was the main reason why I opened this thread: To learn from other teams that had similar solutions and to learn more on how Limelight worked. I recognize all’s comments on how some aspects would be unfair, and I totally agree with all. While some thoughts are not from mine, I personally felt terrible for them.

I would like to take this opportunity to apologize from all for taking their times to discuss this. If I were to actually transfer my thoughts to words much better, then this would never happen in the first place. Well, this is what some ESOL people (or a non-native English speaker) do. Apologies once more.

You did absolutely nothing wrong! The whole point of ChiefDelphi is discussion. Without your question, the discussion would have never existed.

There are some great resources that came out of this thread

Suffice to say, software IP law is… very convoluted.

As I understand it, tinkering with the Limelight software for personal use, installing completely different software on the Limelight hardware, and installing the Limelight software on different hardware are all probably kosher. Distributing a modified version of the Limelight image would almost certainly not be. Complicating the issue is the fact that neither the hardware nor the software is distributed with any kind of licence or EULA.

Disclaimer: I am not a lawyer.

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I think you are conflating what is right and wrong with what is legal and illegal.

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Just a thought, how would people feel about teams buying a limelight then copying the software onto a separate raspberry pi? This wouldn’t be stealing from limelight, but teams would be able to put the cost of a raspberry pi plus leds on the BOM instead of a limelight.

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AFAIK, software that comes with a device is tied to that physical hardware in terms of license agreements.
The best example for that might be how Windows comes in pre-installed with laptops. Assume that there’s a laptop w/FreeDOS priced at x and w/Windows at x+40, while the license itself for a standalone Windows is around 100. The way that the laptop at x+40 can be priced that way is because it’s tied to the hardware, but if you buy the standalone license you can do anything with it, and using license from x+40 laptop anywhere else would be a license breach. I don’t know if that makes sense but just throwing this as an idea.

With all due respect towards the Limelight team, how is running their publicly distributed software on compatible hardware “stealing”? I agree that teams should be buying the Limelight if they want to use the software, but I don’t think it’s wrong to be using the software without buying the hardware, especially since teams can’t buy one unless they’re lucky enough to get one right after a restock.

However, there are going to be several open-source options much like the Limelight’s software available next year. Using those instead of LL would be better for multiple reasons, including the reasons laid out in this thread.

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My understanding is the software is distributed with the intent of it being used with official Limelight hardware.

There is certainly a decent amount of engineering that went into the software. By using it on unofficial devices and not paying for it you are “stealing” their effort that went into the creation of the software.

The only difference between the Limelight software and the Windows example used above is that Windows has DRM that enforces the fact that the license to use the software is tied to the hardware, whereas the Limelight images rely on consumer goodwill.

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Most of the windows licenses that come preinstalled on prebuilts and such are actually transferable. I have never come across a license I couldn’t transfer, with the exception of devices that were bought through a contract by a corporation or school (which are usually enterprise licenses anyway).

Edit: I also think it isn’t fair to compare against something like windows. You can buy standalone copies of windows, but limelight has no option to buy just the software.

That’s not the only difference. It’s not even the most important difference. The most important difference is that windows does in fact have a license that specifies what use is allowed, whereas the limelight software does not.

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I think this is actually the best point yet. Not having a EULA complicates the argument.

The key here is “publicly distributed”. We don’t know if it’s publicly distributed. The Limelight team didn’t put a user agreement on their site so distribution rules are ambiguous.

All in all, if you want the Limelight software OR hardware so badly, I think you a) have to unfortunately wait until they come back in stock, b) read their documentation, learn the algorithms they use, and create your own software that you can run on a PI, or c) use some of the other tools in this thread that effectively do the same thing as a Limelight, but without the Limelight “special sauce”