FAQ: live streaming and using Clevercast player

Live Streaming

Do all live streams work on mobile?

Yes. Clevercast Player works on every modern device and browser. The embedded player will show all available closed captions and audio languages through a dropdown menu, also on iOS and Android devices.

Clevercast does real-time cloud transcoding of your broadcast into multiple video resolutions which are all available to the player. A typical adaptive set is 1080p, 720p, 480p, 360p and 240p. For each viewer, Clevercast Player will automatically choose the best possible resolution and switch to a different one if necessary (depending on screen size, bandwidth, GPU, CPU).

Do you have worldwide coverage? How many viewers can watch a live stream?

Clevercast uses global CDNs (currently Akamai) for live stream delivery, so viewers anywhere in the world will receive the stream from a local server. The number of viewers is almost unlimited. But if you expect more than 100.000 simultaneous viewers, we would appreciate a heads-up.

What about China?

Only companies located in China and having a specific Chinese business license are allowed to use edge servers in mainland China. This also applies to global CDNs that provide worldwide delivery. Since we’re not a Chinese company, we don’t have such a license.

But the global CDNs we use for stream delivery have other edge servers which are geographically sufficiently close (e.g. Hongkong) for HD video streaming to viewers in mainland China. In practice, our live streams have good reception in China (extensively tested by several of our customers). But since the Chinese government requires all traffic to pass through their Great Firewall – over which they have full control – there is no way to guarantee this with complete certainty.

What if my interpreters are located in a different continent?

Interpreters who are located in a different continent will have higher latency, which doesn’t pose a problem in itself. There is, however, a higher risk for packet loss and jitter, which may cause disturbances. We highly recommend thoroughly testing the quality of the interpeter audio in advance. You can use the connectivity test for interpreters too (found under Live > T@H connection tests).

Can my live stream start automatically with sound?

NO. Because most browser builders have decided that video autoplay with sound is not appropriate behaviour. If you want autoplay, you must ensure the live stream initially starts without sound. Otherwise most browsers won't allow the autoplay. Note that this is also the case for Video on-Demand.

There are a few exceptions, but they depend entirely on the behavior of each individual viewer on your website or platform. It has nothing to do with the video player you choose, your player settings, the way of streaming… So it is beyond your control as a content owner.

• Safari doesn’t allow unmuted autoplay anymore.
• Firefox allows autoplay with sound for users that have previously interacted with the domain (such as clicking or pressing buttons).
• Google Chrome keeps a so-called Media Engagement Index (MEI) which measures the extent to which the user plays video with sound on each site. This is the reason why Google Chrome will do autoplay with sound on some sites (eg YouTube) by default: “If you don’t have browsing history, Chrome allows autoplay for over 1,000 sites where we see that the highest percentage of visitors play media with sound. As you browse the web, that list changes as Chrome learns and enables autoplay on sites where you play media with sound during most of your visits, and disables it on sites where you don’t.”
• Microsoft Edge allows users to decide for themselves by adjusting their browser settings, both in general and for certain sites.
• Mobile browsers: autoplay is rarely ever permitted on mobile devices. In general, mobile viewers always have to press the play button.

Finally, keep in mind that browsers can change their behaviour with every new upgrade. So even if unmuted autoplay works now in a certain browser, that doesn’t mean it will still work tomorrow. We therefore strongly recommend to ALWAYS COMBINE THE AUTOPLAY AND MUTED PROPERTIES of your player profile.

What if I configure a player to start automatically with sound?

Most browsers will stop the autoplay: the viewer will have to press the play button to start the stream. Therefore, you should never create a player profile with autoplay, not muted and no controls. In that case, there won't be a play button to press, so the viewer has no way to start the stream.

Can I limit the accessibility of the live stream?

You can create white- and blacklists for countries, domains and IP addresses by creating viewing profiles. Clevercast Player will check these before showing the live stream.

The player does not limit the number of viewers. If you need this, you can use our webinar solution where the player is hosted on a (branded) webinar page. This supports viewer registration and invitation, and can limit the number of simultaneous viewers.

How many languages are possible per live stream?

The number of closed captions is unlimited. The number of audio languages is also unlimited if you use Translate@Home. If you do a multilingual broadcast, the number of audio languages is limited by the capacities of your SRT or RTMP encoder.

Your plan determines how many languages can be used in total (sum of audio languages and closed captions). For audio languages, the floor audio is also counted as a language.

Can I have a fully redundant live stream?

Yes. Clevercast has a main and backup ingest server, to which you can broadcast at the same time. If the main broadcast or live stream delivery is interrupted, Clevercast Player automatically detects this and switches to the backup stream.

This works for all live streams. For T@H and manual transcription however, it does require interpreters to switch from the main to the backup room (only the video and floor audio will failover automatically). See

What is the latency of a live stream?

By default, we use HTTP Live Streaming (HLS) with segments of 6-10 seconds. Due to player buffering this will result in a typical latency of 18-30 seconds, but this may be higher on some connections and devices (with a maximum of 2 minutes on iOS devices).

For custom projects, we may be able to configure your account to use smaller HLS segments and latency. But take into account that this also results in the player doing less buffering, which causes disruptions to viewers with a slow internet connection.

Can viewers watch the live stream on other platforms?

A lot of platforms allow a third-party player to be embedded (e.g. Swapcard, Docedo, Slido, Hubilo, Prezi …). In that case, it suffices to copy the direct link or embed code to the platform for Clevercast player to appear.

Single-language streams can be simulcasted via RTMP to other platforms. For multilingual live streams, Clevercast lets you simulcast a combination of the video stream and a selected translation to single-language platforms via RTMP (e.g. to YouTube, Facebook, Twitter).

Clevercast Player

Can I customize the look and feel of my embedded player?

Yes. You can create your own branded player profile (via the Media -> Players menu) and select this as the player for your event. You can also use our Player API.

Is it possible to enable autoplay for all browsers?

Yes, if you set the ‘muted‘ property of the player profile, so the stream starts playing without audio. Most browsers do not allow to set both the ‘muted‘ property and the ‘autoplay‘ property. See also: 'Can my live stream start automatically with sound?' above.

Can I hide the pause button in the live player?

The pause button is hidden by default in the ‘Live player‘, which is the default player used for live streaming (except in older accounts, where you can change the default player yourself). You can also hide it in other player profiles.

Note that iOS devices use their own native player when going fullscreen. So viewers on iOS will still see a pause button, unless you force the use of Clevercast player on iOS. To do this, set ‘Force use of Clevercast player controls on iOS’ to “Yes” in the player profile. In that case, the player will do a ‘fake’ fullscreen on iOS: the fullscreen button will enlarge the player canvas as much as possible while still staying in the browser.

Is it possible to render the player with a certain audio or captions language?

You can embed the player with a default language of your choice, by adding the audio_default option to the embed code with an ISO 639-1 code (e.g. ‘en’ for English). For captions, use the captions_default and captions_default_show options.

For example, to set the French audio and caption language to be automatically selected when the player is rendered, you can add the following to your embed code: &audio_default=fr&captions_default=fr&captions_default_show=1.

When someone opens the player for the first time, the French audio and captions languages will be automatically selected. Note: when the player is opened the next time, it will remember the viewer’s selection.

It is also possible to use ‘audio_default=browser’ instead of an ISO 639-1 code. In that case, the player will auto-select the browser language if this is one of the translations (otherwise it falls back to the default language). Or you can use our Player API to change the language selection dynamically.

Can I use my own player?

Clevercast uses the HTTP Live Streaming (HLS) protocol. If your player supports this, it should be possible. But by doing this, you will lose all integrated features of Clevercast player like failover, status switching, countdown timer, multilingual menus…

Please let us know if you intend to use your own player. It is not included in our basic support.

Can Clevercast also host the page on which the video is embedded?

Yes, you can use our Webinar solution if you don’t want to host the video on your own site. In that case, you can limit the number of viewers by requiring them to register or by inviting them.