This page contains a summary of best practices for the Live Stream API. If you are just starting out with the Live Stream API, refer to one of the Quickstarts.
Use the SRT protocol if possible
When creating the input endpoint, there are two options for the source stream
protocol:
RTMP_PUSH and SRT_PUSH.
The SRT protocol is preferred over RTMP because SRT is more advanced and
provides additional features such as the following:
- Packet drop recovery
- Forward error correction
- Support for multiple audio elementary streams
- Higher bandwidth
The choice of streaming protocol requires a proper encoder/transcoder that provides that feature. Most professional-grade encoders support SRT.
Recommended bitrates
Use the following bitrates depending on the source resolution and framerate. Higher bitrates directly correlate to higher quality.
| Resolution (ScanMode)/Framerate | H.264 Bitrate (Mbps) |
|---|---|
| 576i/25 and 480i/29.97 | 3 |
| 720p/25/30 | 8 |
| 720p/50/60 | 15 |
| 1080i/25 and 1080i/29.97 | 12 |
| 1080p/50 and 1080p/60 | 20 |
For the output channel resolution and bitrate, depending on the input resolution/frame rate (60 FPS), add the higher frame rate step for 60 FPS if it applies. Note that adding additional steps requires more computing power. The following is the recommended ladder:
| Resolution (ScanMode)/Framerate | H.264 High Profile Bitrate (Kbps) |
|---|---|
| 416x234 p25/30 | 150 |
| 640x360 p25/30 | 400 |
| 768x432 p25/30 | 750 |
| 768x432 p25/30 | 1100 |
| 960x540 p25/30 | 2200 |
| 1280x720 p25/30 | 3300 |
| 1280x720 p50/60 | 5500 |
| 1920x1080 p25/30 | 6000 |
| 1920x1080 p50/60 | 9000 |
For audio, the recommendations are based on the number of channels:
| Channels | AAC Bitrate (Kbps) |
|---|---|
| 2.0 | 64 |
| 2.0 | 160 |
| 5.1 | 384 |