Re-encodes all .mp4 files in the same folder as the script to decrease their size

transcode_all_mp4.ps1

$location = Get-Location
$files = Get-ChildItem $location -Filter "*.mp4" | Sort-Object CreationTime
$quality = "36"
$counter = 0
$total = $files.Length

# Change Write-Progress Style
$PSStyle.Progress.MaxWidth = 240

Write-Host "Transcoding all mp4 files in this directory to mkv using NVENC AV1 with CQ $quality"

# Create directory .\transcoded if it doesn't exist 
if (-Not (Test-Path ".\transcoded" -PathType Container)) {
  New-Item ".\transcoded" -ItemType Directory | Out-Null
}
# Create directory .\original if it doesn't exist
if (-Not (Test-Path ".\original" -PathType Container)) {
  New-Item ".\original" -ItemType Directory | Out-Null
}

function Show-Progress {
  $perc = [Math]::Floor(($counter/$total)*100)
  Write-Progress -Activity "Transcoding Videos" -Status "$perc% ($counter/$total)" -PercentComplete $perc
}

foreach ($file in $files) {
  Show-Progress
  $arguments = "-y -c:v h264_cuvid -hwaccel_output_format cuda -loglevel error -i `"$file`" -fps_mode passthrough -c:v av1_nvenc -cq $quality -c:a copy -map 0:v -map 0:a"
  # Write-Host "Transcoding `"$($file.name)`" -> `"transcoded\$($file.BaseName).mkv`""
  Start-Process -Wait -NoNewWindow -FilePath "ffmpeg.exe" -WorkingDirectory $location -ArgumentList "$arguments `"transcoded\$($file.BaseName).mkv`""
  # Write-Host "Moving `"$file`" -> `"original\$($file.name)`""
  Move-Item -Path $file -Destination "original\$($file.name)"
  $counter++
}

Show-Progress

$before = (Get-ChildItem .\original\ | Measure-Object Length -Sum).sum / 1Gb
$after = (Get-ChildItem .\transcoded\ | Measure-Object Length -Sum).sum / 1Gb
$smaller = [math]::Round(((($after / $before)-1)*-100),2)

Write-Host "`nDone.`n"
Write-Host "Before:"("{0:N2} GB" -f ($before))
Write-Host "After:"("{0:N2} GB ($smaller% Smaller)" -f ($after))

V3 now using AV1 with Nvidia NVENC Encoding
Quality target is set to 36 tuned for 1440p 60fps videos