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Ultra-Low Latency (ULL)

BlendVision One offers Ultra-Low Latency (ULL) live streaming, achieving latencies of less than 3 seconds.

This technology provides your audience with a real-time and interactive viewing experience, making it ideal for applications where minimal delay is critical.


Enabling ULL for Your Livestream

To enable ULL for your livestreams, set the ull_enabled to true during creation:

POST /bv/cms/v1/lives

"ull_enabled":true

ULL Mechanism

Ultra-Low Latency (ULL) focuses on minimizing the delay between capturing a video and presenting it to viewers.

However, the mechanism varies on different platforms due to technical limitations (MSE support):

  • LL-DASH (Chrome, Android): The mechanism gently catches up by slightly speeding up playback to achieve a sub-3-second latency. This approach ensures a smooth playback experience. Typically, it takes approximately 20-30 seconds to reach within the 3-second latency goal.

  • LL-HLS (Safari, iOS): The mechanism skips ahead to catch up, resulting in an instant reduction of latency to below 3 seconds. However, some video frames may be skipped in the process. To prevent unexpected jitter or buffering, the catch-up mechanism is activated only when the latency exceeds 15 seconds.

Viewers have the flexibility to choose their preferred playback platform based on their preferences — a smoother viewing experience (LL-DASH) or a faster catch-up (LL-HLS).

Limitation

Supported DRM for ULL: FairPlay, Widevine