Streaming & Encoding Best Practices

To ensure the highest quality playback experience, you should always begin with the highest quality content possible.

Aspect Ratio

To ensure video content is not stretched inappropriately during playback you should ensure your source content is encoded with the correct display aspect ratio and square pixels. Ensuring your aspect ratio is the same as your playback locations will prevent black bars from being displayed on your content during playback.

Profile – Baseline, Main or High?

The profile determines how the H.264 codec compresses the stream. Greater compression produces smaller streams; less compression generally means better quality. Profiles are based on the streaming application:

  • High is geared for high-definition playback devices.
  • Main is suited for standard-definition broadcast and desktop streaming.
  • Baseline is suited for playback on mobile devices and for compatibility with older playback devices.

Bitrate

When preparing your source encode, you should allow for 40% of your total bandwidth overhead, that means if you have a 10Mbps connection you should not exceed 6Mbps on your encoder.

You can test your upload bandwidth at https://www.speedtest.net/

RTMPS, WebRTC & SRT

For optimal security of your streams, we recommend using the RTMPS stream URL and key. This will encrypt your live stream.

WebRTC & SRT ingest streaming will be available soon!

Low Latency Streaming

Currently the CDN is configured with 10s segment durations which will see an approximate 20-25s latency. The key to reducing latency is reducing the segment durations and we will be looking to support this really soon!

Encoder Examples

The following examples offer a great place to start.

Full HD 1080p

obs-1080p.png
  • Resolution / Output: 1920 x 1080
  • Video Bitrate: 2000 – 4500Kbps
  • Keyframe Interval: 2 Seconds
  • Profile: Main or High
  • Audio Bitrate: 128 Kbps AAC

HD 720p

  • Resolution / Output: 1280 x 720
  • Video Bitrate: 850 – 3000 Kbps
  • Keyframe Interval: 2 Seconds
  • Profile: Main or High
  • Audio Bitrate: 96 Kbps AAC

SD 480p

  • Resolution / Output: 852 x 480
  • Video Bitrate: 500 – 2000 Kbps
  • Keyframe Interval: 2 Seconds
  • Profile: Main or High
  • Audio Bitrate: 96 Kbps AAC

LD 240p

  • Resolution / Output: 320 x 240
  • Video Bitrate: 300 – 850 Kbps
  • Keyframe Interval: 2 Seconds
  • Profile: Baseline
  • Audio Bitrate: 64 Kbps AAC

Like this article?

Share on facebook
Share on Facebook
Share on twitter
Share on Twitter
Share on linkedin
Share on Linkdin
Share on pinterest
Share on Pinterest

Leave a comment