RGBroadcast

Make a light look like a television is on, so an empty house looks occupied.

Occupancy simulation usually replays recorded on/off history, or blinks lights on a timer. Neither looks like the one thing that most says "someone is home" to anyone watching from outside: the flickering, colour-shifting glow of a screen. RGBroadcast drives any controllable light to produce that glow, with distinct content styles (film, news, sport, and so on) and broadcast-style ad breaks, so an evening looks like a person watching television rather than a script running.

It pairs well with a conventional presence simulation such as presence_simulation: let that handle the rest of the house, and let RGBroadcast handle the living room.

What it does

• Works on almost any light. It auto-detects what your light can do (full colour, colour temperature, brightness only) and degrades gracefully. There is no "what kind of light is this" question to answer.
• Random walk, not random flicker. Consecutive states are related, so it reads as a screen rather than a disco. Brightness variation, the strongest cue through a curtain, does most of the work.
• Content styles. film, news, sport, action, game, latenight, plus a schedule that rotates through the evening with nightly randomisation so no two nights match.
• Ad breaks. Broadcast-style breaks every 12 to 18 minutes: a couple of minutes of brighter, faster, more saturated output, which is a distinctive tell of live television.
• Coordinated multiple lights. One "screen" light does the full swing; extra "spill" lights are lit as if by it, staying dimmer and trailing its colour, so a room with a lamp beside the telly looks right.
• Live control. Style, intensity and ad breaks are entities, so you can adjust them from a dashboard or an automation while the simulation is running, without a reload.

Installation

Via HACS (custom repository)

1. In HACS, choose Custom repositories.
2. Add https://github.com/SiteRelEnby/rgbroadcast with category Integration.
3. Install RGBroadcast, then restart Home Assistant.

Manual

Copy custom_components/rgbroadcast into your Home Assistant config/custom_components directory and restart.

Setup

1. Settings → Devices & services → Add integration → RGBroadcast.

2. Pick a screen light (the main one). Optionally add spill lights.

3. That creates a device with these entities:

   Entity	What it does
   switch.<name>	Runs the simulation while on.
   select.<name>_style	Content style, or schedule.
   number.<name>_intensity	0.5 to 2.0. The single realism dial.
   switch.<name>_ad_breaks	Enable broadcast-style ad breaks.
   binary_sensor.<name>_ad_break	On during an ad break (diagnostic).

Turn the main switch on and watch the light. To tune it, put the intensity slider on a dashboard, watch the light through the curtain from outside, and adjust live.

Important: exclude the light from Recorder

Running for a few hours produces well over a thousand state changes per hour per light, each carrying full colour attributes, for history that has no analytical value. Exclude the driven lights from Recorder, or your database will grow fast:

# configuration.yaml
recorder:
  exclude:
    entities:
      - light.living_room_lamp

RGBroadcast already suppresses back-to-back identical commands, but the effect is inherently chatty by design. This is the one bit of manual configuration worth not skipping.

If your light snaps instead of fading

Some lights, Matter lights especially, report that they support smooth transitions and then jump instantly instead. Home Assistant has no way to know this in advance, and there is no software fallback: the transition is sent and silently ignored.

If your light looks steppy or jumpy where it should be smooth, turn on Force stepped rendering in the integration's options. RGBroadcast will then drive it with frequent small changes instead of relying on the device to interpolate, which looks smooth on a light that lies about transitions.

The other options there:

• Force capability tier for a light that misreports what it can do.
• Never use colour temperature to keep a colour-capable light on RGB.
• Brightness ceiling to scale everything down for a dim room.
• Minimum / maximum update interval if the light falls behind (raise the minimum) or you want it calmer.
• When stopped: fade out and turn off, or restore the light's previous state.

How it decides what your light can do

Tier	Light has	Behaviour
Hybrid	colour and colour temperature	Colour temperature for pale scenes, colour for vivid ones
Colour	colour only	Hue, saturation and brightness
Colour temp	colour temperature only	Warm/cool white and brightness
Brightness	dimmable only	Brightness only, still surprisingly convincing
On/off	neither	Cannot be simulated; setup will tell you

Development

python -m venv .venv
.venv/bin/pip install -r requirements-test.txt
.venv/bin/pytest
.venv/bin/ruff check custom_components tests

The visual logic (walk.py, renderer.py, schedule.py) is pure Python with no Home Assistant dependency, so the realism model is tested exhaustively without a running instance. See tests/.

Licence

MIT. See LICENSE.