Powershell Import / Export photo into / from AD

$photopath = d:\photo\aaa.jpg
$photo = [byte[]](Get-Content $photopath -Encoding byte)
Set-ADUser $username -Replace @{thumbnailPhoto=$photo}

$photopath = d:\photo\aaa.jpg
$user = Get-ADUser $username -Properties thumbnailPhoto
$user.thumbnailPhoto | Set-Content $photopath -Encoding byte