Your performance can include live audio-visual streams, which are sent to UpStage using a separate streaming application and can then be placed on your stage and operated in real time in the same way as other media objects – moved, scaled, rotated and so on – as part of your cyberformance.
A stream can be video (image) only, audio only, or both. You can also stream a video file, your desktop, or mix audio in your favourite DJing application and send the audio stream to UpStage as a soundtrack.
The following chapters explain how to set up and send a stream from your phone or computer to UpStage, and how to operate the stream on your stage. The applications that we recommend are OBS (for computers) and Larix Broadcaster (for mobile devices). Other applications can also be used, but we have provided screenshots and step-by-step instructions for these two applications as we have found them to be good.
But first, some important points to understand about streaming in UpStage …
Streaming versus audio-visual conferencing
It’s helpful to understand the difference between audio-visual conferencing platforms (such as Jit.si, BBB, Zoom, Skype, etc.) and a real-time interactive multimedia platform such as UpStage.
Platforms that are purpose-built for audio-visual conferencing use specific (and often proprietary) technologies and protocols and have dedicated high capacity servers. The primary feature of these platforms is streaming.On the other hand, UpStage has a great many other features besides streaming, and requires HTML-compliant streaming functionality as everything is delivered to the browser. As an open source project we are using the best open source streaming server technologies that we have found.
Streams in UpStage normally have around 2-3 seconds of lag (delay) and this will vary according to each individual’s internet connection and their device’s CPU. We choose to see this as a feature of the environment rather than as a problem, and we look for creative and interesting ways to work with delay.
Keeping it light
To minimize lag and ensure the best possible experience, even for those on slower internet connections, you should keep your stream as light as possible. Minimising file size is a good habit with all UpStage media – we are working online and in real time, so speed is more important than high definition for your audience’s best experience.
You will need to experiment with settings including the size, resolution and bitrate of your stream to find the best compromise between speed and quality – and the best settings will depend on variables such as how big you need your stream to be on the stage and what level of quality is aesthetically appropriate for your performance. See the chapter Sending a Stream for optimisation tips.
Theoretically there is no limit to how many streams can be active on a stage at one time. However, the more streams there are, the more data is being processed by the server and by the audience’s devices; so the more streams you have at one time, the greater the chance of lag and other performance issues.
Audio feedback can be created by re-transmitting audio from UpStage back into UpStage via your stream. The easiest way to avoid this is to use headphones, so that your microphone cannot pick up any of the sound from UpStage, however this may not always be possible – for example when there is more than one person at the stream location, and they both or all need to hear the audio from UpStage.
It is advisable to keep the audio input in your streaming application muted all the time, except when you are sure you want to send audio. You can also mute the browser, so that no audio is heard from UpStage, when you are sending your audio stream.
If you need to send an audio stream from a location where the UpStage audio is being played over a sound system, it’s best to use a good quality directional mic and have it as far away from the speakers as possible. When all else fails and the feedback builds, mute your audio stream and wait for it to quieten.
Sometimes a stream may freeze, or stop, for an individual player or audience member. This is usually caused by either a blip in their internet connection, or their device cannot process all the data. Usually it can be solved by that person reloading the stage. If others are receiving the stream normally then the issue is a local one, not a problem with UpStage.
UpStage’s Replay recording feature does not record streams. It is a log of all the actions on the stage, not a screen recording; so the data of a stream will not be saved as part of the replay. You will need to make a screen capture recording in order to have a full recording of a performance that includes streams.