PowerShellで字幕のsubファイルをsrt形式に変換するスクリプト

$inFile = "D:\work\taiiku\taiiku.sub"
$outFile = "D:\work\taiiku\taiiku.srt"

$reader = New-Object System.IO.StreamReader($inFile, [System.Text.Encoding]::GetEncoding("utf-8"))
$writer = New-Object System.IO.StreamWriter($outFile, $false, [System.Text.Encoding]::GetEncoding("utf-8"))

$i = 0

while (($line = $reader.ReadLine()) -ne $null)
{
    if ($line -match '(\d\d:\d\d:\d\d)\.?(\d*),(\d\d:\d\d:\d\d)\.?(\d*)')
    {
        $i++
        $writer.WriteLine($i)

        $str = "{0},{1:000} --> {2},{3:000}" -f $Matches[1], ([int]$Matches[2]/10000), $Matches[3], ([int]$Matches[4]/10000)

        $writer.WriteLine($str)
    }
    else
    {
        $writer.WriteLine($line)
    }
}
$reader.Close()
$writer.Close()

# 終了
Write-Host("終了")