Efficient products for your streaming infrastructure


Low Latency HLS

Softvelum tools can stream and play Low Latency HLS


Low Latency HLS is the next generation of Apple's HTTP Live Streaming protocol to achieve latency of less than two seconds.
Media server and media player must be compliant with Low Latency HLS spec to make it work.
Softvelum covers both sides.


Notice: with latest updates of LL HLS spec draft from Apple, our products now have the outdated implementations for described features.
We do not recommend using them. Full support is coming soon, stay tuned.

Nimble Streamer

Nimble Streamer®

Nimble Streamer transforms live content into Low Latency HLS.
Any supported protocol like RTMP or SRT can be used as a source.


Introduction article describes Nimble Streamer setup and LL-HLS usage.

SLDP Player

SLDP Player

iOS SLDP Player allows playing HLS in Low Latency mode.
SDK provides an easy way to add playback into your apps.

Apple hasn't yet released Low Latency from beta stage. So this feature is available only for SLDP Player SDK subscribers. You can get SDK and build your app to try this technology.
Subscribe for iOS SDK if you'd like to get it.



Why Low Latency HLS?

HLS of RFC8216 is currently a de-facto standard for live and VOD delivery. Chunks of content with simple playlists delivered over HTTP/1.1 give the simplicity of implementation, wide platforms availability, adaptive bitrate (ABR) support, easy caching and scalability. These advantages allowed it to get the biggest share of customer base.
However this approach has its disadvantages for live streaming. The chunk size recommended by Apple is 6 seconds which practically means up to 20 seconds of delay at the start of a live stream. Reducing chunk size further decreases the latency however that has its limit too. ABR also suffers delays in case of rendition switch.

Low Latency extension of HLS enables low latency video streaming.

  • Partial segments (parts) can be accessed before full chunks of content are available.
  • Server side can use HTTP/2 Push for sending parts.
  • Holding playlist requests for obtaining latest parts as soon as they appear.
  • H.264/AVC and H.265/HEVC content can be delivered.
  • Full backwards compatibility with legacy HLS. The players not capable of this protocol extension will play the same streams with regular latency.
  • You can produce a single stream for both optimized and old players.

Nimble Streamer is fully capable of streaming Low Latency HLS:

  • Nimble can package it from any available live source such as RTMP, SRT, RTSP, MPEG-TS or Icecast.
  • It allows using fMP4 (CMAF), audio-only and MPEGTS containers.
  • Live Transcoder decodes and encodes live content between supported codecs, along with building transformation chains.
  • WMSPanel provides wide reporting capabilities
  • Read introduction article to find out more about Nimble Streamer setup.

SLDP Player app allows playing full-featured LL HLS on iOS devices.
As mentioned above, this feature is available in SLDP Player only for SDK subscribers.
If you'd like to build your own low latency app, you can get player iOS SLDP Player SDK for further integration.


Apple Low Latency HLS provides up to two seconds of delay on iOS devices.
How about sub-second latency on HTML5, Android or iOS?
Use SLDP ultra-low latency technology.