that'll do

CrashCourse.md

@@ -111,7 +111,7 @@ In PowerShell files and folders are called items. Some useful cmdlets for workin
 Here's how to loop through files in a folder using [`Get-ChildItem`](https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.management/get-childitem?view=powershell-7.3#description):
 
 ```powershell
-foreach ($image Get-ChildItem $path -Include *.png) {
+foreach ($image Get-ChildItem .\images\* -Include *.png) {
     Write-Host $image.BaseName
 }
 ```

pixup.ps1

@@ -0,0 +1,29 @@
+param(
+    [validatescript({ Test-Path $_ -PathType Any })]
+    [system.io.fileinfo]$in,
+    $out = (Split-Path -Parent $in),
+    $scale = 128
+)
+
+if (!(Get-Command "magick.exe" -ErrorAction SilentlyContinue)) {
+    Write-Host "There's no magick.exe to work with!"
+    Exit-PSHostProcess
+}
+
+if (Test-Path $in -PathType container) {
+    Write-Host $in.DirectoryName
+    $out_dir = "$out\x$scale\"
+    if (!(Test-Path $out_dir)) {
+        New-Item "$out_dir" -ItemType directory
+    }
+    foreach ($image in Get-ChildItem "$in*" -Include *.png) {
+        $scaled = "$out_dir$($image.BaseName)$($image.Extension)"
+        Write-Host $scaled
+        magick $image.FullName -scale "$($scale * 100)%" $scaled
+    }
+}
+else {
+    $scaled = "$out\$($in.BaseName)-x$scale$($in.Extension)"
+    Write-Host $scaled
+    magick $in.FullName -scale "$($scale * 100)%" $scaled
+}