$TARGETSIZE = 2800;


Add-Type -AssemblyName System.Windows.Forms

$ofd = New-Object System.Windows.Forms.OpenFileDialog -Property @{
    InitialDirectory = [Environment]::GetFolderPath('Desktop')
    Multiselect = $true
}

if ($ofd.ShowDialog() -ne "OK") {
    exit
}


$ofd.FileNames | foreach {
    echo converting $_
    $fileName = [System.IO.Path]::GetFileNameWithoutExtension($_)
    $filePath = [System.IO.Path]::GetDirectoryName($_)
    $convertedFilePath = [System.IO.Path]::Combine($filePath, "$($fileName)_4chan.webm")
    $fileInfo = $(ffprobe -v quiet -print_format json -show_format -show_streams "$($_)" | ConvertFrom-Json)
    $duration = $fileInfo.format.duration

    $targetRate = "$([Math]::Round([Math]::Min($TARGETSIZE * 8 / $duration, 4000)))k"

    ffmpeg -y -i "$($_)" -vf "scale=-1:`'min(ih,720)`'" -sn -an -c:v libvpx -b:v $targetRate -quality best -f webm -pass 1 NUL
    ffmpeg -y -i "$($_)" -vf "scale=-1:`'min(ih,720)`'" -sn -an -c:v libvpx -b:v $targetRate -quality best -f webm -pass 2 "$($convertedFilePath)"

    echo "saved to $convertedFilePath `n`n`n"
}