SpotifyLeds

Audio-reactive LED controller. Captures system audio (e.g. Spotify) on macOS via BlackHole, runs it through one of four effects, and streams pixels over UDP to a WLED-flashed strip. A mobile-friendly web UI lets you change mode, palette, and per-effect parameters in real time.

Spotify ──▶ BlackHole ──▶ PyAudio ──▶ effect ──▶ UDP ──▶ WLED strip
                                         ▲
                                  HTTP control panel
                                  (phone or browser)

Prerequisites

• Python 3.9+
• BlackHole 2ch installed and set up as a Multi-Output Device alongside your speakers, so audio plays and gets captured
• A WLED-flashed ESP32/ESP8266 LED controller reachable on your LAN, with UDP Realtime enabled (DRGB/WARLS on port 19446 by default)
• Python deps: pyaudio, numpy

pip install pyaudio numpy

Configuration

Hardware constants live at the top of spotify_led_http.py. Edit these to match your setup:

WLED_IP = "192.168.1.124"   # your WLED controller's IP
WLED_PORT = 19446           # WLED UDP realtime port
HTTP_PORT = 8080            # web UI port
NUM_LEDS = 90
COLOR_ORDER = "RGB"         # try "GRB" if colors look swapped

Audio device selection is automatic — the script searches for any input device with BlackHole in its name. Use TestingScripts/list_audio_devices.py to see what's available if it can't find one.

Running

python3 spotify_led_http.py

It prints the web UI URL on startup, e.g. http://yourmac.local:8080/. Open it on your phone to control the strip live.

File layout

File	Purpose
spotify_led_http.py	Entry point. Audio capture loop, settings store, HTTP wiring.
led_effects.py	Palettes, gradient builder, four effect classes, WLED UDP packet builder.
web_ui.py	http.server-based JSON API. State management is injected via callables.
index.html	Mobile-first control panel (vanilla JS, no build step).
TestingScripts/	Standalone helpers: audio device enumeration, a sACN/DMX smoke test, and an earlier prototype.

Web UI

• GET / — control panel (served from index.html)
• GET /state — current settings as JSON, plus enum metadata (palette/mode/boundary lists)
• POST /state — JSON patch of any subset of settings; unknown keys and out-of-range values are dropped
• POST /randomize — re-rolls mode, color mode, palette, and color

The audio loop and HTTP handler share settings under a lock; structural changes (mode, color_mode, agents_count) rebuild the effect, while tunables update live without resetting effect state.

Effects

Mode	Behavior
pulse	Every LED flashes at its assigned color, scaled by an audio envelope with attack/release/gamma.
progressive	LEDs light left-to-right; the lit count tracks the audio level.
twinkle	Random LEDs sparkle on and fade out. Density scales with audio.
agents	Moving pixels with fading tails; speed reacts to audio, optional rising-edge direction flips on peaks.

Color modes apply to all effects:

• solid — every LED uses one chosen color
• palette_linear — LED i uses the i-th color of the palette (rotates over time)
• palette_random — each LED picks a random palette color, fixed across frames

Palettes

All palettes are defined in led_effects.py as ordered RGB stops; palette_gradient linearly interpolates them across the strip.

Name	Vibe	Stops (hex)
rainbow	Full-spectrum rainbow, loops back to red	#FF0000 #FFFF00 #00FF00 #00FFFF #0000FF #FF00FF #FF0000
fire	Black → red → orange → yellow → white	#000000 #800000 #FF0000 #FF8000 #FFFF00 #FFFFFF
ocean	Deep navy through cyan to pale aqua	#000020 #004080 #0080FF #80FFFF
sunset	Dusky violet, hot pink, orange, gold	#140028 #FF0080 #FF8000 #FFDC50
forest	Dark green through bright leaf-green	#001000 #005010 #20A020 #B4DC50
purples	Dark plum to lavender pink	#140028 #5000A0 #B450FF #FFC8FF
purplesgreens	Moody, low-brightness purple/green alternation	#280028 #001000 #140014 #002000
lava	Black → dark red → molten orange-red	#000000 #3C0000 #C81E00 #FF6400 #FFC83C #FF3200
embers	Glowing coals; low overall brightness	#000000 #280000 #A01400 #FF5014 #5A0A00
arctic	Navy → icy blue → white	#081020 #2864B4 #8CC8FF #F0FFFF #B4DCF0
neon	Hot pink, cyan, lime, magenta — all max-saturation	#FF00C8 #00FFF0 #C8FF00 #FF3CC8
synthwave	Retro purple/magenta/cyan	#14003C #FF00B4 #5000C8 #00DCFF #3C0078
cyberpunk	Mostly dark with green accents and bright pops	#000000 #002800 #00781E #28DC3C #A0FFB4 #003C0A
autumn	Browns, burnt orange, gold	#1E0800 #B43200 #DC6E00 #F0B41E #6E320A
tropical	Teal, mint, gold, coral, magenta	#006464 #28DCC8 #FFC850 #FF6450 #C83296
mint	Dark teal through mint to near-white	#001E1E #28B48C #A0F0C8 #F0FFF0 #3CC8B4
candy	Bright pink, teal, gold, purple	#FF3CA0 #28C8B4 #FFB428 #A03CF0 #FF64C8
berry	Deep aubergine through hot pink and magenta	#140014 #780042 #DC0064 #FF50A0 #8C0050
citrus	Yellow, orange, lime — all bright	#FFF03C #FFA000 #B4DC00 #FFC828