How important is low latency? It depends on what you’re streaming. For standard live streams like online news, your viewers won’t likely notice a 10-second lag. On the other hand, if you’re building interactive video experiences for online gaming or e-commerce, even five seconds of latency could ruin the entire event.
In our 2022/2023 Video Developer Report, live low latency ranked as the second-biggest challenge that content distributors are experiencing with video technology. It’s also the area where survey participants see the most opportunity for innovation in their service. Despite this, 47% of those surveyed indicated that they weren’t using low-latency streaming technology.
Video Developer Report 2022/23: Which technology do you use for low-latency streaming?
So what gives? Why would latency rank as a top concern when almost half of the developers participating in our report aren’t leveraging technologies designed to reduce video lag?
As it turns out, ‘low latency’ is a relative term. For some, sub-five seconds is the ultimate goal. But for truly interactive video applications (like online betting, live auctions, and multi-player quizzes) playback delay often needs to be in the hundreds of milliseconds.
There’s also the issue of perceived need. In conversations with customers, we’ve found that video distributors fall into one of three camps:
- They absolutely need low-latency or real-time streaming to ensure that the viewer experience is high quality and competitive in their market.
- They think they need to decrease latency because there is so much buzz surrounding the topic, but in reality, reducing the lag has minimal impact on how well the content is received.
- They’re well aware that quality and scalability are more important factors for their audience, and as a result, aren’t investing resources in driving down latency.
Take it from our Chief Architect Igor Oreper:
“A better question may not be how do I minimize my live stream’s delay? but what is the target latency I want my audience to have? Target latency can make a world of difference to the playback experience you’re offering your viewers.”
– Igor Oreper (Chief Architect, Bitmovin)
Source: Low Latency vs. Target Latency: Why there isn’t always a need for speed
How does live encoding impact latency?
For use cases where reducing latency is a must, there are multiple opportunities to decrease the broadcast delay across the video supply chain. The live encoder, packager, CDN, and player must all be optimised accordingly.
Things that can impact the speed of video encoding include the encoder itself, which codec and protocols you use, and configurations like the bitrate and resolution.
Broadcasters committed to lightning-speed delivery should look for contribution encoders that support:
- Low-latency protocols like SRT and Zixi
- Ethernet connectivity
Additionally, you might have to compromise on quality by decreasing frame rate and resolution if low latency is essential.
More information at Live Streaming Encoders: Top 20 Compared