upconvert.ps1

param (
  [string]$src = ".",
  [string]$dst = ".\reencode"
)

# Add-Type -AssemblyName System.Windows.Forms

function time($block) {
    $sw = [Diagnostics.Stopwatch]::StartNew()
    &$block
    $sw.Stop()
    $sw.Elapsed
}

function touch ($file) { new-item -force -ItemType "file" -path $file.toString() }

function encode ( $file, $dst ) {
    # $file = get-childitem $file
    $fn = $file.Name
    $full = $file.fullname
    $ext = $file.extension
    $fd =  $file.DirectoryName.Replace($pwd, "")
    Write-Host "doin the conversion of $full, and it's going to $dst"

    $inp = ".\inp-$fn"
    $out = ".\out-$fn"
    mkdir $inp
    mkdir $out

    $framerate = ./ffprobe -v error -select_streams v:0 -show_entries stream=avg_frame_rate -of default=noprint_wrappers=1:nokey=1  $full
    $height = ./ffprobe -v error -select_streams v:0 -show_entries stream=height -of default=noprint_wrappers=1:nokey=1 $full
    $width = ./ffprobe -v error -select_streams v:0 -show_entries stream=width -of default=noprint_wrappers=1:nokey=1 $full

    $frame_height = 720.0 # 1080.0
    $frame_width = 1280.0 # 1920.0
    # $scale = [math]::min(1080.0/$height, 1920.0/$width) # full HD
    $scale = [math]::min($frame_height/$height, $frame_width/$width) # not quite full HD

    write-output "Framerate: $framerate`nHeight: $height`nWidth: $width`nScale: $scale"

    $time = time {
      & .\ffmpeg.exe -i $full -f image2 "$inp\seq-%09d.png"
    }
    write-output $time

    Write-output "Enhancing images to $out.  Scale is $scale"
    $dur = time {
      & .\waifu2x-cudnn\waifu2x-caffe-cui.exe -p "cudnn" -s $scale -n 3 -i $inp -o $out -model_dir ".\waifu2x-cudnn"
    }
    $dur = $dur.TotalSeconds
    Write-Output "...took $dur seconds"

    $img_height = ./ffprobe -v error -select_streams v:0 -show_entries stream=height -of default=noprint_wrappers=1:nokey=1 "$out\seq-000000001.png"
    $img_width = ./ffprobe -v error -select_streams v:0 -show_entries stream=width -of default=noprint_wrappers=1:nokey=1 "$out\seq-000000001.png"

    touch $dst
    $time = time {
      # add this for padding: https://ffmpeg.org/ffmpeg-filters.html#pad
      # -vf "pad=width=$($frame_height):height=$($frame_width):x=$(calc_me):y=$(calc_me):color=black"
      # -aspect $frame_width/$frame_height
      # 
      # maybe this also:
      # -filter:a loudnorm
      & .\ffmpeg.exe -y -framerate $framerate -f image2 -i "$out\seq-%09d.png" -vcodec h264 -pix_fmt yuv420p "temp$ext"
      & .\ffmpeg.exe -y -i "$full" -i "temp$ext" -map 1:v -c copy -map 0 -map -0:v $dst.toString()
    }
    write-output $time

    # Write-Host "Press any key to continue ..."
    # $host.UI.RawUI.ReadKey("NoEcho,IncludeKeyDown")
    Remove-Item -path "$inp" -recurse
    Remove-Item -path "$out" -recurse
    # .\ffmpeg -i $file.fullname -vcodec copy -acodec copy -scodec copy -map 0 ".\REENCODE$fd\$fn" 24000/1001
}

$extns = "\.(mp4|mkv|avi|ogm)"

time {
  $src = get-item $src
  new-item -path $dst -ItemType "directory"
  $dst = "$(get-item $dst)\"

  $files = get-childitem -path $src -recurse
  foreach ($f in $files) {
    $extn = [IO.Path]::GetExtension($f)

    if ($extn -match $extns) {
      time {
        $d = $f.fullname.toString().Replace($src.toString(), $dst.toString())
        write-output "Encoding $f to $d"
        encode -file $f -dst $d
      }
    }
  }

  Write-Output "Done!"
}