Copy-LockscreenImages.ps1

# PowerShell script to copy the images Windows 10 uses for its lockscreen to
# the users Pictures folder in two subdirectories:
# *'Wallpapers widescreen' (for images that are wider than they are tall) and
# *'Wallpapers longscreen' (for images that are taller than they are wide).
# The subdirectories will be created if they do not exist.
#
# Run this script (as admin) with '-task' to create a scheduled task that will
# automatically run this script when you log in. The script will register
# itself at its current location, with its current filename. Put the script in
# a place where you want to keep it before creating the task!

param(
    [switch]$task = $false
)

# Create the scheduled task
if($task){
    $description = "Copies the images that Windows uses on the lockscreen to Pictures so that they can be used as wallpapers"
    $action = New-ScheduledTaskAction -Execute 'Powershell.exe' -Argument ('-NoProfile -NoLogo -NonInteractive -ExecutionPolicy Bypass -File "'+$PSCommandPath+'"')
    $trigger =  New-ScheduledTaskTrigger -AtLogOn -User ([System.Security.Principal.WindowsIdentity]::GetCurrent().Name)
    Register-ScheduledTask -Action $action -Trigger $trigger -TaskName "Copy Lockscreen Images" -Description $description
}

add-type -AssemblyName System.Drawing

# This is the secret path where Windows 10 keeps its lockscreen images. If you
# open this folder yourself, you'll see a bunch of files with long hexadecimal
# numbers as names and no extensions. If you rename the files to
# 'something.jpg' you'll find that some, but not all, are actually images. The
# folder includes all sorts of images used by Windows, including the icons for
# Candy Crush and other 'promotional' games. But it also includes our precious
# lockscreen images in both landscape and portrait orientations.
$source_path = Join-Path -Path $env:LOCALAPPDATA -ChildPath "Packages\Microsoft.Windows.ContentDeliveryManager_cw5n1h2txyewy\LocalState\Assets\"

# We'll store the images in you 'Pictures' folder.
$base_path = [environment]::GetFolderPath('MyPictures')

# This is the path for landscape images.
$wide_path = Join-Path -Path $base_path -ChildPath "Wallpapers widescreen\"
if(!(Test-Path $wide_path)){
    New-Item -ItemType Directory -Force -Path $wide_path
}
# This is the path for portrait images.
$long_path = Join-Path -Path $base_path -ChildPath "Wallpapers longscreen\"
if(!(Test-Path $long_path)){
    New-Item -ItemType Directory -Force -Path $long_path
}

# Let's get a list of all files in our source path.
$filelist = Get-ChildItem $source_path
foreach($file in $filelist){
    # Try to load the file as an image.
    try{
        $img = [System.Drawing.Image]::FromFile($file.FullName);
    }
    # If this fails, it wasn't an image and we can skip to the next file.
    catch{
        continue;
    }
    # If the image is smaller than 1 Megapixel it's too small for a wallpaper.
    if($img.width * $img.height -lt 1000000){
        continue;
    }

    # Add ".jpg" to the name of the file and copy it the the right directory.
    # While a long hexadecimal number might not be the catchiest of names, at
    # least it's unique and helps us avoid multiple copies of the same image.
    $target_path = $file.name + ".jpg"
    if($img.width -gt $img.height){
        $target_path = Join-Path -Path $wide_path -ChildPath $target_path
    } else {
        $target_path = Join-Path -Path $long_path -ChildPath $target_path
    }
    Copy-Item $file.FullName $target_path
}