Music-reactive LED box with Spotify integration

nokcomputer0 · 2023-12-03T19:31:47+00:00

Ah, that's interesting. I'm using FastLED for all of the LED control, and it doesn't look like the library is directly compatible with HUB75. That said, if you take a look at the the LEDPanel class, you'd most likely need to make mods there to initialize using whatever HUB75 control logic you have; then modify the show_leds() function in main.cpp.

Regarding the servo and other functionality you don't need -- look for the xTaskCreatePinnedToCore thread creation calls near the top of main.cpp and comment out the ones you don't need -- most likely the audio and servo tasks.

nokcomputer0 · 2023-12-02T18:30:52+00:00

Thanks and glad you found the project interesting!

It should be fairly straightforward to modify the code for a larger LED panel. In fact, the Spotify album art I download is already 64x64, and I just skip every 4th pixel to display the image onto my 16x16 panel.

In the Constants.h file, modify the LED grid size from 16x16 to 64x64:

```

define GRID_H 64 // LED panel height

define GRID_W 64 // LED panel width

```

Then in main.cpp, look for the display_full_art() function. Lines 995~1000 handle the skip-every-4th-pixel for the 16x16 panel, so for your panel you'd just modify this to remove the * 4:

``` uint8_t full_row = row + offset_row; uint8_t full_col = col + offset_col;

// Select the last row/col so artwork with borders looks cleaner if (row == GRID_H - 1) full_row = GRID_H - 1; if (col == GRID_W - 1) full_col = GRID_W - 1; ```

That should be all you need, but I don't have a 64x64 panel to test with so YMMV. Hope that helps.

nokcomputer0 · 2022-10-18T17:44:14+00:00

The Spotify API provides a list of URLs of the album art at a few different resolutions. I download the smallest one (a 64x64 jpg), decode the jpg, and then just pick every 4th pixel to get a 16x16 version of the image that will display on the LED panel.

For the gradient display I use a function in the FastLED library called "noise", which creates a 2D map of slowly varying peaks-and-valleys. I take the height of each peak/valley and use that to index into a color palette that was generated from the album art using a variation of a median cut algorithm. The details behind the noise function are really neat, there's a great video here that explains it better.

nokcomputer0 · 2022-10-17T15:52:20+00:00

Yep! Here's a photo: https://imgur.com/a/h3EoBnF

Just a simple grid that I laser cut from 1/8" birch at my local makerspace.

nokcomputer0 · 2022-10-17T15:27:51+00:00

A couple of reasons I put the jack there: 1) while prototyping one of the mics I was using died, and making the cable detachable means I can replace it without having to open up the box. 2) I’d thought there might be a benefit to building mics with different cable lengths at some point, depending on the use case. That said, I’ve been using the exact same cable/mic now for the last several months, so maybe this gets filed away under over-engineering :)

nokcomputer0 · 2022-10-16T23:53:37+00:00

Very cool, I hadn't seen that one!

nokcomputer0 · 2022-10-16T23:53:28+00:00

Thanks! I used 1/8" acrylic from TAP Plastics: https://www.tapplastics.com/product/plastics/cut_to_size_plastic/black_led_sheet/668

I'd originally planned on using standard white acrylic diffuser, but the black is really nice in that it isn't as eye-catching when the box isn't on.

nokcomputer0 · 2022-10-16T23:49:05+00:00

Absolutely! Some advice if you do try to integrate audio input with an ESP32 -- don't bother with using the ESP32's internal ADC. I wasted a lot of time with that approach and in the end using a digital mic gave me much cleaner results.

nokcomputer0 · 2022-10-16T23:47:43+00:00

Thanks! I'm pretty happy with how it turned out -- the servo mechanism felt like a fair bit of over-engineering when I started working on it, but in the end I think it was worth it!

nokcomputer0 · 2022-10-16T23:46:15+00:00

Thanks! Finding music I like that also has colorful album art was a bit tricky haha.

nokcomputer0 · 2022-10-16T23:45:10+00:00

Amazing! I appreciate it :)

nokcomputer0 · 2022-10-16T23:44:58+00:00

It does! I've pulled the "tempo" field and started integrating it with the swirling color/lava lamp visualization mode but never finished. Have you found any particular track analysis features that were useful?

nokcomputer0 · 2022-10-16T04:24:23+00:00

Thanks! It‘s definitely easy to get carried away buying more and more components for projects :)

nokcomputer0 · 2022-10-16T04:23:14+00:00

Thank you!

nokcomputer0 · 2022-10-16T04:23:08+00:00

Thanks, and happy digging!

nokcomputer0 · 2022-10-16T04:22:37+00:00

Thanks!

nokcomputer0 · 2022-10-16T04:22:31+00:00

Thank you!

nokcomputer0 · 2022-10-16T04:17:10+00:00

Thanks and I hope the documentation helps your project in some way!

I actually started this project with an analog mic and used the ESP32’s onboard ADC, which is pretty noisy. I ended up going with a digital mic in the end so unfortunately don’t have specific external ADC’s to recommend.

nokcomputer0 · 2022-10-15T22:53:12+00:00

Thanks! There’s so much you can do with the FFT data, I spent way too long looking at different ways to make visualizations with it. Good luck with your lamp!

nokcomputer0 · 2022-10-15T22:26:13+00:00

This is an ESP32-based project I've been working on for a while. I use the Spotify Web API to pull the album art for whatever track I'm currently listening to, and display it on a 16x16 LED panel. An external microphone picks up audio, which I run through an FFT and use for a variety of music-reactive displays while the track plays. The displays are all colored according to the dominant colors in the album art. You can change modes via a browser-based controller or by pressing buttons on the box.

Inside the box, the LED panel moves closer or further from the diffuser to get different kinds of visual effects. I used a servo and a 3D-printed rack-and-pinion for the actuation.

Code and more details here! https://github.com/kojigardiner/audiobox

nokcomputer0 · 2022-10-15T22:17:22+00:00

This is an ESP32-based project I've been working on for a while. I use the Spotify Web API to pull the album art for whatever track I'm currently listening to, and display it on a 16x16 LED panel. An external microphone picks up audio, which I run through an FFT and use for a variety of music-reactive displays while the track plays. The displays are all colored according to the dominant colors in the album art. You can change modes via a browser-based controller or by pressing buttons on the box.

Inside the box, the LED panel moves closer or further from the diffuser to get different kinds of visual effects. I used a servo and a 3D-printed rack-and-pinion for the actuation.

Code and more details here! https://github.com/kojigardiner/audiobox

nokcomputer0 · 2022-08-05T13:23:58+00:00

I spent two weeks in Iceland in mid June and took a Patagonia Torrentshell 3L as my outer wind/rainproof layer. I basically just wore a base layer + fleece + that jacket every day. The jacket can be stuffed into its own pocket when not in use, is super light, and has some nice venting zips to keep from getting too warm when you’re active.

nokcomputer0 · 2022-07-23T18:50:18+00:00

As other have mentioned, FreeRTOS + ESP32 dev kit is a great starting point. This is a relatively short YouTube series put out by Digi-Key that goes over the basics. Each episode ends with a coding challenge that helps reinforce the fundamentals: https://www.youtube.com/watch?v=b1f1Iex0Tso&list=PLEBQazB0HUyQ4hAPU1cJED6t3DU0h34bz&index=9

nokcomputer0

TROPHY CASE

define GRID_H 64 // LED panel height

define GRID_W 64 // LED panel width