nightd

screen dimmer for android tv
keep your media playing while the screen goes dark

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what is this?

nightd is a tiny android tv app that blacks out your screen while keeping your media playing. perfect for:

• falling asleep to music/podcasts - screen goes dark, audio keeps playing
• saving power on oled displays - no burn-in, no wasted pixels
• background audio - cast audio without lighting up your room

modes

mode	what it does
dim	single overlay layer (~40% darker)
black	5 stacked layers = pitch black (android limits overlay opacity to 80%, so we stack 'em)

cycle order: off → dim → black → off

installation

1. download the latest nightd.apk
2. sideload via adb: adb install nightd.apk
3. grant "display over other apps" permission when prompted

usage

with key mapper (recommended)

use key mapper to bind nightd to remote buttons:

action	intent
toggle	com.sudox.nightd.TOGGLE
dim mode	com.sudox.nightd.DIM
black mode	com.sudox.nightd.BLACK
turn off	com.sudox.nightd.OFF

package: com.sudox.nightd
service: com.sudox.nightd.NightdService

example: bind "zoom in" to toggle, "zoom out" to off.

with adb

# toggle (cycles through off → dim → black → off)
adb shell am startservice -a com.sudox.nightd.TOGGLE com.sudox.nightd/.NightdService

# specific modes
adb shell am startservice -a com.sudox.nightd.DIM com.sudox.nightd/.NightdService
adb shell am startservice -a com.sudox.nightd.BLACK com.sudox.nightd/.NightdService
adb shell am startservice -a com.sudox.nightd.OFF com.sudox.nightd/.NightdService

how it works

android limits overlay opacity to 80% per layer. to achieve true black, nightd stacks 5 layers:

0.8 × 0.8 × 0.8 × 0.8 × 0.8 = 0.032 (96.8% blocked)

plus it sets screen brightness to 0 for good measure.

permissions

• SYSTEM_ALERT_WINDOW - required to draw overlay
• FOREGROUND_SERVICE - keeps the overlay running
• WRITE_SETTINGS - adjusts screen brightness (optional, gracefully fails)

building from source

# clone
git clone https://github.com/sudoxnym/nightd.git
cd nightd

# build (requires android ndk)
./gradlew assembleRelease

# or use the aapt/d8/apksigner toolchain directly

license

MIT - do whatever you want with it.

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_{built by sudoxnym for the sleep-deprived}