Convert from webm to mp4:x

function convert(input, output, callback) {
  if (debug) {
    console.log("CONVERTING");
    console.log("IN: " + input);
    console.log("OUT: " + output);
  }
  ffmpeg(input)
    .outputOptions([
      "-i clipdrop_logo.png",  // Logo WaterMark Input
      "-loglevel panic",
      "-preset veryfast",
      "-movflags faststart",
      "-vf scale=-1:480",
      "-c:v libx264",
      "-crf 23",
      "-c:a aac",
      "-bitrate 2000000",
      "-maxrate 2200000",
      "-bufsize 1500000",
      "-filter_complex \"overlay=main_w-overlay_w-5:main_h-overlay_h-5\""  // Logo WaterMark Settings
    ])
    .on("end", function () {
      if (debug) {
        console.log("conversion ended");
      }
      callback(null);
    })
    .on("error", function (err) {
      if (debug) {
        console.log("error x: ", err);
      }
      callback(err);
    })
    .saveToFile(output);
}