trim-latest-obs-video.ts

// Name: Trim latest OBS video

import "@johnlindquist/kit";

const { stdout } = await $`ls -t ~/Movies/*.mp4 | head -n 1`;

const inputVideo = stdout.trim();

const outputVideo = home("Movies", "trimmed", path.parse(inputVideo).base);

const THRESH = "-40";
const DURATION = "1";

const output =
  await $`source ~/.bash_profile && ffmpeg -hide_banner -vn -i ${inputVideo} -af "silencedetect=n=${THRESH}dB:d=${DURATION}" -f null - 2>&1 | grep "silence_end" | awk '{print $5 " " $8}'`;

const silence = output.stdout
  .trim()
  .split("\n")
  .map((line) => line.split(" "))
  .map(([silenceEnd, duration]) => {
    return {
      silenceEnd: parseFloat(silenceEnd),
      duration: parseFloat(duration),
    };
  });

const PADDING = 0.2;

const startTime = silence[0].duration - PADDING;

const endTime =
  silence[silence.length - 1].silenceEnd -
  silence[silence.length - 1].duration +
  PADDING;

const formatFloatForFFmpeg = (num: number) => {
  return num.toFixed(3);
};

await ensureDir(home("Movies", "trimmed"));

await $`source ~/.bash_profile && ffmpeg -y -hide_banner -ss ${formatFloatForFFmpeg(
  startTime,
)} -to ${formatFloatForFFmpeg(
  endTime,
)} -i ${inputVideo} -c copy ${outputVideo}`;

await $`open -R ${outputVideo}`;