Invoke-AIPromptStego.ps1

function Invoke-AIPromptStego {
    param(
        [string]$InFile,
        [string]$OutFile,
        [string]$OutFormat,
        [string]$Prompt
    )

    Add-Type -AssemblyName System.Drawing

    $bytes = [System.IO.File]::ReadAllBytes($InFile)
    $bytes += [System.Text.Encoding]::UTF8.GetBytes([char[]]($Prompt))

    $b64prompt = [System.Convert]::ToBase64String($bytes)
    $binprompt = [System.Convert]::FromBase64String($b64prompt)

    $stream = New-Object System.IO.MemoryStream($binprompt.Length)
    $stream.Write($binprompt, 0, $binprompt.Length)
    $stream.Position = 0

    $img = [System.Drawing.Image]::FromStream($stream, $true, $false)
    $img.Save($OutFile, [System.Drawing.Imaging.ImageFormat]::$OutFormat)
}