I do lighting research, and I want to develop a color-gradient board for educational/visualization purposes of CIELAB and other color appearance models (by the way, HSV is like the literal worst of them all).
I have 6-8 channels of in-house LEDs, and I can determine the duty cycle coefficients for all leds.
Is this something FastLed could do?
I don’t really think they are independently addressable, as we are soldering phosphors onto boards themselves and there’s only one microcontroller.
We went with HSV because it can be done fast and with integer math, and is still better to work with than raw RGB. Remember, FastLED started out life on small 8-bit mcus.
You can do your own higher level color systems though, you would just have to convert them to rgb before writing out the data. And while FastLED itself is tuned to work with addressable led controllers, there is an example (I forget its name off the top of my head, but it’s under examples) for using an analog/pwm output on an avr to drive a raw led.
@Daniel_Garcia Firstly, thank you for the response. I really appreciate you helping a stranger.
Oh of course of course! I would have chosen HSV as well. Also, the more conversions between spaces the more errors there are, especially with low resolutions like this.
Since I can afford to spend a bit (company money) and I want good color resolution and power and control, would it make more sense to look at python and raspberry pi? I do a lot of color analysis in python, so it would be awesome to have a real-world interface with my code to visualize.
Something like this
Depending on how heavy the math is - yeah, you may not want to run it on a small embedded MCU, certainly not one that doesn’t have hardware floating point - if you go the addressable led route, I think you might want to go with a 12-bit or 16-bit driver as well (FastLED doesn’t support 16-bit output yet)
@Daniel_Garcia Ok, well I don’t want to overengineer anything just yet. I’ll start simple with the fastLED lilbrary, an arduino (we have an Uno), and a good resolution ledmatrix display.
Do you have any recommendations for an easy to make led-matrix like the video above? A small pitch would be ideal.
I’m not familiar with color models, but I do know quite a bit about efficiently implementing complex algorithms. Any hints about what sort of color model would be more ideal for low-res LED lighting?
Might also be worth mentioning newer boards have single precision FPU that makes 32 bit float about as fast as 8 bit integers. So even a very complex model should be achievable on those boards, of course with some programming… 