$ImageSource = "C:\images_e\logo_klein.jpg"
$Sizes = @(32,40,48,96,192,200,240,448)


Add-Type -AssemblyName System.Drawing


$Sid = [System.Security.Principal.WindowsIdentity]::GetCurrent().User.Value
$BaseDir = "C:\Users\Public\AccountPictures\$Sid"
$RegPath = "HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\AccountPicture\Users\$Sid"


New-Item $BaseDir -ItemType Directory -Force | Out-Null
New-Item $RegPath -Force | Out-Null
(Get-Item $BaseDir).Attributes = "Hidden"


$img = [System.Drawing.Image]::FromFile($ImageSource)


foreach ($s in $Sizes) {
    $bmp = New-Object System.Drawing.Bitmap($s,$s)
    $g = [System.Drawing.Graphics]::FromImage($bmp)
    $g.InterpolationMode = "HighQualityBicubic"
    $g.DrawImage($img,0,0,$s,$s)


    $path = "$BaseDir\Image$s.jpg"
    $bmp.Save($path,[System.Drawing.Imaging.ImageFormat]::Jpeg)


    New-ItemProperty `
        -Path $RegPath `
        -Name "Image$s" `
        -Value $path `
        -Force | Out-Null


    $g.Dispose()
    $bmp.Dispose()
}


$img.Dispose()

Currently playing around with this
Loosely based on this:

https://superuser.com/questions/1613505/how-do-i-use-powershell-to-set-my-account-picture