Video bandwidths and resolutions used by StarLeaf
Managing Firewall and bandwidthLast updated September 4, 2020
On this page:
- Preferred StarLeaf bit rate
- Portal settings for send and receive rates
- Content and video bandwidth split
- Limitations at low bandwidths
- Speed tests
- In-call media statistics
- StarLeaf app: Platforms with limited processor power
StarLeaf uses the following bit rates and resolutions:
|Room system / client||Max bit rate||Audio (StarLeaf-to-StarLeaf)||Max video receive||Content|
|GT Mini + Touch 2045||6 Mbps*||64 kbps AAC-LD||1080p30||1080p30|
|GT Mini + Touch 2036||2.5 Mbps||64 kbps AAC-LD||720p30||1080p30|
|Huddle||6 Mbps*||64 kbps AAC-LD||1080p30||1080p30|
|StarLeaf Room for Windows||1.5 Mbps||64 kbps AAC-LD||720p30||1080p12|
|StarLeaf Room for Poly||1.5 Mbps||64 kbps AAC-LD||720p30||1080p12|
|StarLeaf app for Windows and macOS||1.5 Mbps||64 kbps AAC-LD||720p30||1080p12|
|StarLeaf app for Android||448 kbps download, 384 kbps upload||64 kbps AAC-LD||352p||1080p6|
|StarLeaf app for iPhone||496 kbps||64 kbps AAC-LD||352p30||1080p6|
|StarLeaf app for iPad (varies depending on model)||Up to 1 Mbps||64 kbps AAC-LD||720p30||1080p6|
|WebRTC||1.5 Mbps||64 kbps AAC-LD||720p30||1080p12|
|H.323 registered devices (excluding Cisco SX80)||1.5 Mbps||64 kbps AAC-LD||720p30||1080p12|
|Cisco SX80||2.5 Mbps||64 kbps AAC-LD||720p30||1080p12|
*GT Mini with Touch 2045 and Huddle support bit rates up to 6 Mbps. However, by default it is limited to 2.5 Mbps to reduce the load on your internet connection. You can update this in the Portal; see below.
In the StarLeaf Portal, you can set maximum send and receive rates at site level and on individual endpoints. By default, these are set to Automatic, meaning it will use the preferred bit rate. You can set a lower bit rate or a higher bit rate up to 6 Mbps.
To adjust these rates, go to Portal > Sites > Edit sites and expand Advanced settings.
If you wish to limit the bandwidth used by the endpoints then you can set a value lower than 2.5 Mbps.
To increase video quality you can set higher bandwidths up to 6 Mbps which will apply to room systems with a GT Mini + Touch 2045 or Huddle.
Setting a higher rate than what an endpoint is capable of will have no effect.
StarLeaf allocates 64 Kbps to audio. The remaining available bandwidth is split between video and content according to the amount of screen space they take up with a maximum of 3 Mbps each.
StarLeaf tests the available internet bandwidth to determine what bit rate to use up to the preferred rate or the rate set in the Portal. At lower bandwidths, StarLeaf restricts the video quality according to:
|Speed test result||Description|
|<152 kbps||Bandwidth is too low for video. Only audio calls are possible|
|<256 kbps||Bandwidth is too low for simultaneous video and content sharing. Only audio plus low-quality video or audio plus content sharing is possible|
|<768 kbps||Bandwidth is too low for HD video. Only audio plus lower quality video and content sharing|
|<1168 kbps||Bandwidth is too low for HD video. Only audio plus lower quality video and content sharing|
|<2.1 Mbps||Bandwidth is good enough for audio and HD video|
|>= 2.1 Mbps||Bandwidth is good enough for simultaneous HD video and content sharing. This only applies to room systems|
Upstream and downstream bandwidths are tested and set independently of each other, meaning that a low upload speed on an ADSL connection, for example, does not have a negative impact on the quality of a video that an endpoint can receive.
To view the current speed test result on your Touch 2045 or Huddle double tap the home button to get to the settings and go to Network. This shows you the most recent upload and download results.
Press Run speed test to re-run the test.
Under the Account tab in your app, you can check your connection speed in Speed test. The speed test advises you of call bandwidth and the quality of video that your app can receive depending on this.
Select Run speed test to check the latest connection status.
Within a call, the actual bit rate of the audio, video, and content sent and received depends on:
- the overall call bit rate and
- the amount of motion and
- the video capabilities of the other meeting participants
Unlike the hardware-based range of StarLeaf endpoints, the StarLeaf app is designed to install and run on platforms with a widely varying range of capabilities. It is able to reduce the bit rate and resolution of its video channel in line with the capabilities of the host CPU. On a modern full-spec PC or laptop, StarLeaf’s capabilities match those described in section 1 of this article. On lower-powered systems, for example mobile devices, lower bit rates and resolutions are selected in order not to over-power the processor.