List of contents:
- How to Encode Multiple Audio Tracks
- How to Serve Multiple Audio Tracks
- How to Use Multiple Audio Tracks with FV Player
Adding multiple audio tracks to your videos opens up a world of possibilities. You can make your video available for as wide range of people as possible, or cater to the specific needs of your users. Subtitles are important, but sometimes they are not enough.
Whether you want to include various language speakers, add a curated commentary to your short film, or even provide your music students with various layers of a song, that's where multiple audio tracks come into play.
How to Encode Multiple Audio Tracks
In order to stream a video with multiple audio tracks, you will need to encode it prior to hosting it anywhere. There are various services and software that will help you do so. We recommend using the free and open-source tool FFmpeg.
The fact that FFmpeg works from a command line instead of having an interface of its own, can be quite intimidating, but there's no need to worry. It is truly powerful and best of its kind. Moreover, it is backed by a huge community of devote users eager to help and provide guides for just about anything.
- Prepare both your video file and all your audio files into a single folder.
- Download FFmpeg here
You might need to take further steps before being able to use FFmpeg successfully. All this depends on your operating system and download choice.
- Once you are sure FFmpeg is properly set up, open your command line and point it to the correct folder first, by inserting the cd (change directory) command. For example:
- Once pointed to the correct folder, insert the encoding command according to this scheme
ffmpeg -i video.mp4 -i audio1.mp3 -i audio2.mp3 -i audio3.mp3 -map 0:v -map 1:a -map 2:a -map 3:a -metadata:s:a:0 language=eng -metadata:s:a:1 language=ger -metadata:s:a:2 language=spa -codec copy name-of-output-video.mp4
If you are adding audio tracks, that are not languages, or wish to name your language tracks differently, instead of language=eng, write title="Your Title"
If you are inserting language instead of title, it is important to insert the correct language shortcuts to ensure, that the language gets recognized.
Note: Multiple audio track files can only be in mp3 or AAC format.
This is the encoding command used for adding multiple audio tracks to the example below. Adding English, German and Spanish language tracks in mp3 format to multiple-audio-tracks-raven.mp4 video and outputting a video called raven-multilangauge.mp4:
ffmpeg -i multiple-audio-tracks-raven.mp4 -i raven_en-edit.mp3 -i raven_de-edit.mp3 -i raven_es-edit.mp3 -map 0:v -map 1:a -map 2:a -map 3:a -metadata:s:a:0 language=eng -metadata:s:a:1 language=ger -metadata:s:a:2 language=spa -codec copy raven-multilanguage.mp4
How to Serve Multiple Audio Tracks
Not all hosting services support using multiple audio tracks. You will also want to encode the files into an HLS Stream to ensure that all browsers will be able to play the video properly.
Vimeo and YouTube do not support multiple audio tracks as of yet. YouTube is currently testing this feature and it could be available to the general public fairly soon.
We recommend using Coconut, as it fully supports multiple audio tracks and you do not need to do anything special.
Amazon Web Services supports multiple audio tracks too. If you already have a working AWS encoding workflow, you can create multiple audio tracks HLS stream by adding the audio selectors in the output section of MediaConvert.
How to Use Multiple Audio Tracks With FV Player
Just insert the link to the shortcode editor as you would a normal video, and FV Player will recognize the multiple audio tracks automatically.
Once posted, the video will have an AUD button on the controlbar, allowing you to switch between the audio tracks.