Livestream Studio can accept multiple audio tracks with different languages via SDI and/or a multi-channel audio interface and send them out to either a single player (via UDP or Zixi only), or simulcast multiple streams, each with a different language selected.
Requirements
To bring multiple languages into Studio, they must come in through a single input with multiple channels of audio (e.g. English in channels 1 and 2, Spanish in channels 3 and 4, and so on. You could also configure one language per channel with each one outputting to L and R). This can typically be achieved using an external audio mixer going into a camera, which then outputs SDI into your Studio system. We’ve also tested the Behringer UMC404HD interface successfully.
If you wish to have a single stream where viewers can choose which language they hear in the destination player, your streaming provider will need to include a server that can accept MPEG-TS output. Currently, neither Vimeo nor Livestream support this workflow, but you can learn more about how to set it up with Wowza here.
The alternative is to simulcast from Studio to multiple destinations (e.g. three separate Vimeo events). You can choose which language each event should output in the Stream tab; this is described in further detail below.
If neither setup works for you, we'd love to hear your feedback.
Language configuration
To setup multiple languages in Studio, navigate to Settings: Multi-language Events and check Enable Multi-language Events.
Select the input that the multiple audio channels with the different languages are coming in.
You can add up to 16 languages. Use the + / - buttons to add and remove language tracks, then use the drop-down menu on the right side to select the desired language. The abbreviations here are based on international language standards; a reference of language codes is available here.
Be sure to add languages in the same order in which they are coming into Studio. For example, if English is coming in via channel 1, add English first. This is so Studio can map them to the correct channel properly (although you can adjust it manually if needed). Save your settings when you're done.
Navigate to the Inputs tab and select the gearwheel of the input with the languages coming in. Select the Audio tab. In addition to Filters, you should see a separate tab for each language you added. This is where you can check and adjust the channels that each language is using in Studio.
If you adjust filters, they will be applied to all available languages. There is currently no way to adjust filters for each language individually.
To monitor the languages coming in, navigate to the Audio tab. A drop-down menu with the various languages will appear under the input you selected in the Settings: Multi-language Events menu. You can use this menu to select which language you monitor locally. This does not impact your stream, but rather gives you a chance to confirm that the correct language is coming through the correct channels.
If you want to listen to audio channels while manually mapping them to languages, try having the audio mixer and the input audio settings open in opposite columns so you can navigate between them seamlessly.
Streaming via UDP or Zixi to a single player
Navigate to the Stream tab and select either UDP or Zixi as your streaming destination. Enter your destination URL into the URL field.
Below this, you can find the Video PID (packet identifier) and each language's audio PID. Studio generates these automatically but you can edit them to be any value between 32-8190. You will need these when creating .stream and SMIL files for Wowza.
Each language will be checked by default, but if for any reason you don't want a language included in a stream, uncheck it and it won't output to Program.
Select Go Live when you're ready to start your stream.
Streaming to multiple destinations with different audio tracks
For all other providers available in Studio, you can achieve a multi-language event by adding multiple streaming destinations. For example, Vimeo Premium allows for up to three simultaneous live events, which would let you broadcast three streams with identical video but different audio at the same time all within one provider.
When you have multi-language events enabled and your languages configured (as described above), you will see a Select Language drop-down menu, allowing you to choose which language will output to that destination. Select a different language for each stream.
Consider including the language in the name of each event (i.e. Vimeo events, Livestream events, Facebook schedule posts) so that your viewers know which one to watch and also so you can easily choose which language to configure for each stream.
Make sure each destination is activated (i.e. is checked at the top of the panel or when you hover over its bottom tab). Select Go Live when you're ready to start streaming; each destination will go live simultaneously.