Compress-Video.ps1

Param(
    [Parameter(Mandatory=$True)]
    [string]$Path,
    [string]$Quality = "36",
    [string]$Preset = "p4",
    [string]$Tune = "hq",
    [string]$Format = "webm",
    [bool]$CopyAudio = $False,
    [switch]$Keep
)

# Write-Progress style
$PSStyle.Progress.MaxWidth = 240
$InFile = Get-ChildItem $Path
$OutFile = "$($InFile.DirectoryName)\$($InFile.BaseName).$Format"
# $OutFile = "$($InFile.BaseName).$Format"
Write-Host $InFile $OutFile
$TempFile = "$env:TEMP/ffmpeg-output.txt"
$TotalFrames = ffprobe.exe "-v" "error" "-select_streams" "v:0" "-count_packets" "-show_entries" "stream=nb_read_packets" "-of" "csv=p=0" $InFile
$CurrentFrame = -1
$FfmpegArgs = @(
    # "-v", "error" # Only log errors
    "-y", # Overwrite if already existing
    "-hwaccel_output_format", "cuda",
    "-c:v", "h264_cuvid", # Use nvidia h264 decoder
    "-i", "`"$InFile`"", # Input file
    "-fps_mode", "passthrough",
    "-map", "0:v", "-map", "0:a", # Map video and audio tracks
    "-map", "0:s?", # Map subtitle track
    "-c:v", "av1_nvenc", # Use nvidia av1 encoder
    "-cq", "$Quality", "-preset", "$Preset", "-tune", "$Tune", # Nvenc av1 qualit and bitrate settings
    "-c:s", "copy" # Don't re-encode subtitle tracks, copy codec
)

if ($CopyAudio) {
    $Format = "mkv"
    $FfmpegArgs.Add("-c:a","copy")
}
$FfmpegArgs += "`"$OutFile`""

# Get current frame from ffmpeg stdout/stderr file
function Get-Frame {
    if (-not(Test-Path -Path $TempFile -PathType Leaf)) {
        try {
            $null = New-Item -ItemType File -Path $TempFile -Force -ErrorAction Stop
        }
        catch {
            throw $_.Exception.Message
        }
    }
    $HasFrame = Select-String -Path $TempFile -Pattern "(frame=\s*)(\d*)" -Quiet
    if (-Not $HasFrame) {
        Return -1
    }
    $Match = Select-String -Path $TempFile -Pattern "(frame=\s*)(\d*)"
    Return [int]$Match.Matches[-1].Groups[2].Value
}


Write-Host -NoNewline "Transcoding... "
Start-Process -FilePath "ffmpeg.exe" -NoNewWindow -ArgumentList $FfmpegArgs -RedirectStandardError $TempFile | Out-Null
$StartTime = $(get-date)

# Get current frame from ffmpeg stdout/stderr file
while ($CurrentFrame -lt $TotalFrames) {
    # $elapsedTime = $(get-date) - $StartTime
    $elapsed = (Get-Date) - $StartTime
    $NewCurrentFrame = Get-Frame
    if ($CurrentFrame -eq $NewCurrentFrame) {
        Continue
    }

    $Percent = [Math]::Round((($CurrentFrame/$TotalFrames) * 100.0), 2)
    if ($Percent -le 0) {
        $eta = 0
    } else {
        $elapsed = (Get-Date) - $StartTime
        $totalTime = ($elapsed.TotalSeconds) / ($Percent / 100.0)
        $remain = $totalTime - $elapsed.TotalSeconds
        $eta = "$([Math]::Floor($remain)) Seconds remaining"
    }

    $CurrentFrame = Get-Frame
    Write-Progress -Activity "Processing video" -Status "Frame $CurrentFrame/$TotalFrames ($Percent%) ETA $eta" -PercentComplete $Percent
    Start-Sleep -Milliseconds 100
}

# Clean up temp file
Remove-Item $TempFile

Write-Host "Done"
Compare-Size -Original $InFile -Compare $OutFile

# Prompt user if the original file should be removed
$reply = $Keep ? "n" : (Read-Host -Prompt "Remove original file? [y/N]")
if ( $reply -eq 'y' ) { 
    Remove-Item $InFile
    Write-Host "Original file removed"
}