New Teams custom backgrounds

Custom backgrounds in Teams offer an excellent opportunity to enhance company branding or promote internal initiatives. However, the recent update to Teams on macOS has altered the deployment process, particularly concerning the location of these backgrounds. In response to requests for background deployment, I've developed a script that can be executed from Intune, Munki, or any platform of your choice. Importantly, this script can be run as either root or the current user, offering flexibility in its application.

In addition the script has some features that makes management easier for you.

• The file can be either an image file or zip file, allowing you to easily deploy multiple backgrounds in one go.
• The thumb image is automatically resized and cropped with correct aspect ratio based on the background image.
• If the image format is not PNG, it is automatically converted to a PNG.

Let's have a look at the script step by step which can be found here.

First, some required parameters are set which should not be changed. These gets the current user and the home folder, creates a temp directory and sets the path to the backgrounds folder:

### Do not modify ###
CURRENT_USER=$( echo "show State:/Users/ConsoleUser" | scutil | awk '/Name :/ { print $3 }' )
USER_HOME=$(dscl . -read /users/${CURRENT_USER} NFSHomeDirectory | cut -d " " -f 2)
TMPDIR=$(mktemp -d)
BACKGROUND_FOLDER="$USER_HOME/Library/Containers/com.microsoft.teams2/Data/Library/Application Support/Microsoft/MSTeams/Backgrounds/Uploads"

To run the script, you only have to set one configuration which is the URL to where the image or zip should be downloaded:

### Required settings ###
BACKGROUND_URL="" # Replace with the URL of the image or zip you want to download

There is also some option configurations such as setting a variable to do a run time check if the script has been run before and should not run again:

### Optional settings ###
IMAGE_FORMATS=("png" "jpg" "jpeg") # Add or remove image formats as needed
RUN_CHECK=false # Set to true to prevent the script from running more than once
RUN_CHECK_FILENAME=".teamsbackground" # Name of the file to check if the script has been run before
RUN_CHECK_PATH="$USER_HOME/Library/Application Support/$RUN_CHECK_FILENAME" # Path to the file to check if the script has been run before

The process_image function is responsible for handling the extraction of the zip file if it is one and then process each image file found:

process_image() {
    local f="$1"
    file_extension="${f##*.}"
    for format in "${IMAGE_FORMATS[@]}"; do
        if [[ "$file_extension" == "$format" ]]; then
            IMAGE_GUID=$(uuidgen)
            IMAGE_PATH="$BACKGROUND_FOLDER/$IMAGE_GUID.png"
            IMAGE_THUMB_PATH="$BACKGROUND_FOLDER/${IMAGE_GUID}_thumb.png"
            # If not a png, sips convert it to png in current folder  
            if [[ $f != *.png ]]; then
                sips -s format png "$f" -o "$f.png" > /dev/null
            fi

            # Rename the file to the GUID in current folder
            mv "$f" "$IMAGE_GUID"
            # Copy the image to the background folder
            cp "$IMAGE_GUID" "$IMAGE_PATH"
            # Copy the thumb file to the background folder
            cp "$IMAGE_GUID" "$IMAGE_THUMB_PATH"

            # Resize the image to have a height of 186, maintaining the aspect ratio
            sips -Z 186 "$IMAGE_THUMB_PATH" -o "$IMAGE_THUMB_PATH" > /dev/null 2>&1
            # Get the current width of the image
            width=$(sips -g pixelWidth "$IMAGE_THUMB_PATH" | awk '/pixelWidth:/{print $2}')
            # Calculate the amount to crop from the sides
            crop=$((($width - 238) / 2))
            # Crop the image to have a width of 238, centered
            sips -z 186 238 "$IMAGE_THUMB_PATH" -o "$IMAGE_THUMB_PATH" > /dev/null 2>&1

            log_message "Background image downloaded and set, image GUID: $IMAGE_GUID"
        fi
    done
}

Running the script, the image or zip will be downloaded and backgrounds and thumbs will be created:

[Tue Feb 20 10:59:16 CET 2024] - Background image downloaded and set, image GUID: F4D42A93-7551-46E3-B0F7-DB98A12A493B
[Tue Feb 20 10:59:20 CET 2024] - Background image downloaded and set, image GUID: BC0390C6-E800-4786-937D-2D5709DD0FD4
[Tue Feb 20 10:59:23 CET 2024] - Background image downloaded and set, image GUID: 3D2DBDE1-3450-4939-AB0B-33CD45929121

If RUN_CHECK has been set to true and the script has run once before, it will not run again:

[Tue Feb 20 11:43:17 CET 2024] - Script has already been run, exiting

Quick post but hopefully this makes it easy for you to deploy custom Teams backgrounds to users using the new Teams.