The BoxCast Low-Latency Preview feature allows you to troubleshoot streaming issues in near real-time from a remote location, no matter your encoder. You can remotely monitor what your camera is sending without waiting for it to be seen by viewers, who are typically on a 30+ second delay to allow for transcoding/transrating of the stream. This allows you to verify camera position, audio levels, etc., much more rapidly as a type of remote confidence monitor.
To use the Low-Latency Preview, here are three options:
Use a supported browser to access a Low-Latency Preview in the BoxCast Dashboard (Preferred)
Use the Broadcaster app to access a Low-Latency Preview on your iOS devices
Use VLC to access a Low-Latency Preview from a Windows or macOS computer
Use a Supported Browser to Access a Low-Latency Preview in the BoxCast Dashboard
In the Dashboard, navigate to the broadcast details page. Click the Show Preview button to the right of the embedded player in the Broadcast Options section.
A low-latency player will appear in place of the regular player. Note: the low-latency player does not have any controls – it will play back in approximately real-time and does not support seeking into the past.
To open the preview in a separate window, click the small “pop-out” icon in the upper-right corner of the low-latency player.
To stop previewing, click the Hide Preview button in the Broadcast Options section.
NOTE: If you are using an RTMP encoder and are unable to see the preview in the Dashboard, be sure you have disabled B-frames in your encoder or try a different browser. See this article for more help with your encoder.
Supported Browsers
The following browsers support the technology needed for low-latency preview:
✅ Chrome (v107 and later)
for all devices on macOS Big Sur 11.0 and later and Android 5.0 and later
for devices with hardware support on Windows 8 and later
for devices with hardware support powered by VAAPI on Linux and ChromeOS
🤷 Other Chromium-based browsers (e.g. Brave) may work; your mileage may vary.
✅ Edge
v79 and later: for devices with hardware support on Windows 10 and later when HEVC video extensions from the Microsoft Store is installed
v107 and later: for all devices on macOS Big Sur 11.0 and later and Android 5.0 and later
✅ Safari (for macOS, v13 and later)
Firefox
✅ h.264/AVC (e.g. broadcasts from BoxCaster, RTMP, Producer): v42 and later
🚫 h.265/HEVC (e.g. broadcasts from Spark, BoxCaster Pro, Producer)
Opera (v94 and later)
✅ h.264/AVC (e.g. broadcasts from BoxCaster, RTMP, Producer)
for all devices on macOS Big Sur 11.0 and later and Android 5.0 and later
for devices with hardware support on Windows 8 and later
for devices with hardware support powered by VAAPI on Linux and ChromeOS
🚫 h.265/HEVC (e.g. broadcasts from Spark, BoxCaster Pro, Producer)
iOS devices:
iPad (v11 and later)
✅ h.264/AVC (e.g. broadcasts from BoxCaster, RTMP, Producer)
🚫 h.265/HEVC (e.g. broadcasts from Spark, BoxCaster Pro, Producer)
🚫 All other devices (e.g. iPhone/iPod)
✅ Preview of all broadcast types supported via the Broadcaster app
Use VLC to Access a Low-Latency Preview from a Windows or macOS computer
To use the Low-Latency Preview feature via VLC, you must be streaming an event using H.264/AVC using a BoxCaster, a third-party RTMP hardware/software encoder, or Producer.
In the Dashboard, navigate to the broadcast details page. You will see the Show Preview button to the right of the embedded player in the Broadcast Options section.
An overlay will appear with instructions; click the Open with VLC button and download the VLC playlist.
Open the downloaded playlist with VLC and the preview will start playing.
Use the Broadcaster App to Access a Low-Latency Preview from an iPhone, iPad, or iPod touch
Open the Broadcaster app on your iOS device.
Locate the live broadcast currently streaming and tap on it.
Locate the "Preview" button near where the BoxCaster (or other stream source) is listed and tap on it.
A full-screen preview of the broadcast will appear.
Important Notes:
The low-latency preview will not show scoreboard overlays, as those are embedded in the video as part of the cloud origin server process later. This tool can be useful, however, in combination with the manual scoreboard controls.
The low-latency preview incurs an approximately 2-3 second delay from real-time.
The preview is not transcoded/transrated, so you must be on a device/network that supports downloading at the full bitrate that you are streaming at. It will not buffer/adjust to adapt to a slower network like the normal viewer playback would.
Other artifacting may be visible in the preview that will not be shown to viewers due to device limitations and the lower latency.
This feature is available on all BoxCast plans except for the Basic plan.