addAudioToVideo

src/services/addAudioToVideo.mts

@@ -0,0 +1,29 @@
+import path from 'node:path'
+import { promises as fs } from 'node:fs'
+
+import tmpDir from 'temp-dir'
+import ffmpeg from 'fluent-ffmpeg'
+
+export const addAudioToVideo = async (videoFilePath: string, audioFilePath: string): Promise<string> => {
+  
+  const tempOutputFilePath = `${videoFilePath.split('.')[0]}-temp.mp4`
+  
+  await new Promise((resolve, reject) => {
+    ffmpeg(videoFilePath)
+      .input(audioFilePath)
+      .outputOptions('-c:v copy')  // use video copy codec
+      .outputOptions('-c:a aac')   // use audio codec
+      .outputOptions('-map 0:v:0') // map video from 0th to 0th
+      .outputOptions('-map 1:a:0') // map audio from 1st to 0th
+      .outputOptions('-shortest') // finish encoding when shortest input stream ends
+      .output(tempOutputFilePath)
+      .on('end', resolve)
+      .on('error', reject)
+      .run()
+  })
+
+  // Now we want to replace the original video file with the new file that has been created
+  await fs.rename(tempOutputFilePath, videoFilePath)
+
+  return videoFilePath
+};