This is script to auto on/off a Logitech light when the webcam is on/off in Mac. It requires hidapitester

litra-auto-on.plist

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
   <key>Label</key>
   <string>litra-auto-on</string>
   <key>ProgramArguments</key>
   <array><string>/Library/LaunchDaemons/litra-auto-on.sh</string></array>
   <key>RunAtLoad</key>
   <true/>
</dict>
</plist>

litra-auto-on.sh

#! /bin/bash

# Download both files and https://github.com/todbot/hidapitester to /Library/LaunchDaemons/
# Execute the following commands to launch it on login
# sudo chown root:wheel /Library/LaunchDaemons/litra-auto-on.plist
# sudo chmod o-w /Library/LaunchDaemons/litra-auto-on.plist
# sudo launchctl load -w /Library/LaunchDaemons/litra-auto-on.plist
# For test it:
# launchctl start litra-auto-on
# tail -f /var/log/system.log

# Use 046D/C900 for older models
model="046D/C901"
# Change to your own path
hidapitester="/Library/LaunchDaemons/hidapitester"


log stream --predicate 'subsystem contains "com.apple.UVCExtension" and composedMessage contains "Post PowerLog"' | while read LOGLINE
do
  [[ "${LOGLINE}" == *"On;"* ]] && eval "$hidapitester --vidpid $model --open --length 20 --send-output 0x11,0xff,0x04,0x1c,0x01"
  [[ "${LOGLINE}" == *"Off;"* ]] && eval "$hidapitester --vidpid $model --open --length 20 --send-output 0x11,0xff,0x04,0x1c"
done

A few people want this to work with iPhone and continuity. Based on the camera events, the log stream below should give you a good place to start and stop the light.

log stream --predicate 'subsystem == "com.apple.CMContinuityCapture" and composedMessage contains "CMContinuityCaptureVideoStream stopStreamAndReturnError"'
log stream --predicate 'subsystem == "com.apple.CMContinuityCapture" and composedMessage contains "CMContinuityCaptureVideoStream stopStreamAndReturnError"'

This script worked great for me, however, if I'm using the webcam a Google Meet call from the PWA to a Chrome window, the light turns off. This doesn't happen if I switch to a different application though.

Does anyone know how to fix this?

I found this to work well for both intel and arm based macs. It's been super reliable for months now, using slack, zoom, or google meet.

log stream --predicate 'eventMessage contains "Cameras changed to"' | while read LOGLINE
do
  # ON
  [[ "${LOGLINE}" == *"changed to [ControlCenterApp.VideoCamera"* ]] && eval "$hidapitester --vidpid $model --open --length 20 --send-output 0x11,0xff,0x04,0x1c,0x01"
  # OFF
  [[ "${LOGLINE}" == *"changed to []"* ]] && eval "$hidapitester --vidpid $model --open --length 20 --send-output 0x11,0xff,0x04,0x1c"
done

Upgraded to Sonoma, the light comes one when you start a video stream, but doesn't turn off when you close it.
I tried using dudo's code too (mine is a bit 'hacky', to be gentle) but same error.

Just upgraded to Sonoma, i'm having a similar issue - Bootstrap failed: 5: Input/output error

I'm using a very slightly modified version of wkoutre's script

This is how mine looks

log stream --predicate 'subsystem contains "com.apple.UVCExtension" and composedMessage contains "Post PowerLog"' | while read LOGLINE
do
	[[ "${LOGLINE}" == *"On;"* ]] && 
    eval "$hidapitester --open-path DevSrvsID:4294974364 --length 20 --send-output 0x11,0xff,0x04,0x1c,0x01" &&
    eval "$hidapitester --open-path DevSrvsID:4294973605 --length 20 --send-output 0x11,0xff,0x04,0x1c,0x01"
	[[ "${LOGLINE}" == *"Off;"* ]] &&
    eval "$hidapitester --open-path DevSrvsID:4294974364 --length 20 --send-output 0x11,0xff,0x04,0x1c" &&
    eval "$hidapitester --open-path DevSrvsID:4294973605 --length 20 --send-output 0x11,0xff,0x04,0x1c"
done

Running the commands in order, sudo launchctl bootstrap system /Library/LaunchDaemons/litra-auto-on.plist gives me the boostrap error, but if I unload first, then bootstrap it doesn't error - but lights no longer react

I disabled the script entirely on my machine, but the light still comes on when I boot the computer.

Just managed to get mine running - had to start and stop the service a few times and then it just started working. Weird.

For Macbook air m2 @sonoma this variation is working for me

log stream --predicate 'eventMessage contains "Cameras changed to"' | while read LOGLINE
do
  # OFF
  [[ "${LOGLINE}" == *"appEffects: []"* ]] && eval "$hidapitester --vidpid $model --open --length 20 --send-output 0x11,0xff,0x04,0x1c"
  # ON
  [[ "${LOGLINE}" == *"appEffects: [ControlCenterAp"* ]] && eval "$hidapitester --vidpid $model --open --length 20 --send-output 0x11,0xff,0x04,0x1c,0x01"
done

I am on an M1 on Sonoma, and I am not getting anything to work. Like someone mentioned before, it will automatically turn on both on login and when starting the camera, but it seems to do that even with the script disabled. It never turns off. My logs look like this for on, then off:

So I have my script looking like so:

log stream --predicate 'eventMessage contains "Cameras changed to"' | while read LOGLINE
do
  # ON
  [[ "${LOGLINE}" == *"changed to [ControlCenterApp.VideoCamera"* ]] && eval "$hidapitester --vidpid $model --open --length 20 --send-output 0x11,0xff,0x04,0x1c,0x01"
  # OFF
  [[ "${LOGLINE}" == *"changed to [:]"* ]] && eval "$hidapitester --vidpid $model --open --length 20 --send-output 0x11,0xff,0x04,0x1c"
done

I even confirmed that the eval command definitely works, but for some reason, I am having trouble detecting that log for off. Do I need an escape character for the : perhaps?

Anyone else have any luck?

The script I am using (ijcarson1's one above) started working correctly after rebooting the computer a couple of times. No idea why.

I think I finally got it for my setup (MacBook Pro M1 Ultra)
I used this script:

log stream --predicate 'eventMessage contains[c] "cameras changed to "' | while read LOGLINE;

do
  # ON
  [[ "${LOGLINE}" == *"changed to [ControlCenterApp.VideoCamera"* ]] && eval "$hidapitester --vidpid $model --open --length 20 --send-output 0x11,0xff,0x04,0x1c,0x01";
  # OFF
  [[ "${LOGLINE}" == *"changed to [:]"* ]] && eval "$hidapitester --vidpid $model --open --length 20 --send-output 0x11,0xff,0x04,0x1c";
done

Note: I added [c] for case insensitivity (that is what was breaking between off and on), and I made sure to run these to reset:

launchctl stop litra-auto-on
sudo launchctl load -w /Library/LaunchDaemons/litra-auto-on.plist;
sudo launchctl load -w /Library/LaunchDaemons/litra-auto-on.plist;
# the next line errors, so not positive if it is necessary or not
sudo launchctl bootstrap system /Library/LaunchDaemons/litra-auto-on.plist
launchctl start litra-auto-on

Hope this helps someone!

Hi Everybody,

Just a note that we have now integrated official support for Litra Lights being turned automatically on/off in the October 2023 release of GHub. This version will roll out to all users over the next week or two.

Excellent news! Thank you Aron & Logitech engineering team. Quick question - will this be supported in LogiOptions + as well or do we have to install both GHub for the Litra and logioptions+ separately for other devices?

This is only supported in GHub right now.

Thanks for adding this feature to GHub!

Now all I need is to be able to manually turn it off using one of the programmable keys in my Logitech MX Keys. @aronrosenberg Are you looking to enable that feature?

You should already be able to assign Litra actions to a G key, just look for it under the assignments section for your keyboard.

The Logitech MX Keys doesn't have G keys and it's not detected by GHub, only Logi Options+.

I missed the part where you said you had a MX Keys. That device is currently only supported in Options+ which does not have the Litra auto-on/off functionality at this time.

Ideally there will only be one software for everything but I can live with having the auto on/off in GHub, if I'm able to have Smart actions for the light in Options+ to toggle it on/off manually, which are missing.

@aronrosenberg Nice that this is now supported by Logitech G-Hub. Is there any progress with a native Apple Silicon version that doesn't require Rosetta?