如何在特定的视频秒级为视频文件添加背景音乐？在node-fluent-ffmpeg中

const ffmpeg = require('fluent-ffmpeg');

const inputPath = 'path/to/input-video.mp4';
const outputPath = 'path/to/output-video.mp4';
ffmpeg(inputPath)
  .output(outputPath);

const backgroundMusicPath = 'path/to/background-music.mp3';
ffmpeg(inputPath)
  .input(backgroundMusicPath)
  .addOption('-map 0')
  .addOption('-map 1')
  .output(outputPath);

ffmpeg(inputPath)
  .input(backgroundMusicPath)
  .addOption('-map 0')
  .addOption('-map 1')
  .output(outputPath)
  .outputOption('-c:v libx264')
  .outputOption('-c:a aac')
  .outputOption('-b:v 1M')
  .outputOption('-shortest');

ffmpeg(inputPath)
  .input(backgroundMusicPath)
  .addOption('-map 0')
  .addOption('-map 1')
  .output(outputPath)
  .outputOption('-c:v libx264')
  .outputOption('-c:a aac')
  .outputOption('-b:v 1M')
  .outputOption('-shortest')
  .run();