HLS (HTTP Live streaming) is a new streaming protocol that Apple released in 2009 that can be distributed through a common Web server. Apple's official HLS solution for the live video service, the main scope of the program is:
- Live streaming with IPhone, IPod Touch, IPad, and Apple TV. (MAC can also be used)
- No special service software is used to stream live media.
- Requires a video-on-demand service via encryption and authentication (authentication).
HLS is designed to enable users to perform streaming media playback on Apple devices, including Mac OS X, via normal Web services. HLS supports streaming live and on-demand services, as well as multiple backup streams at different bit rates (usually based on the current speed to adapt to the sharpness of the video), so that the client can adjust to the current network bandwidth to only the current video stream. In terms of security, HLS provides encryption of media files via HTTPS encryption and authentication of users, allowing video publishers to protect their networks. compared to the common streaming live broadcast protocol, such as RTMP protocol, RTSP protocol, MMS protocol, the biggest difference of HLS live is that the live client obtains, not a complete data stream. The HLS protocol stores the live stream as a continuous, short-length media file (mpeg-ts format) on the server side, while the client constantly downloads and plays these small files because the server side always generates new small files with the latest live data. So that the client as long as the sequential playback of the files obtained from the server, the implementation of the live broadcast. As a result, HLS can be thought of as an on-demand technical way to achieve live broadcasting,This technical feature of HLS determines that its latency will always be higher than the normal streaming live protocol. HLS only requests basic HTTP messages, and unlike real-time Transport Protocol (RTP), HLS can pass through any firewall or proxy server that allows HTTP data to pass through. It is also easy to use a content distribution network to transfer media streams. because the data through the HTTP protocol transmission, so completely do not consider the firewall or proxy problems, and the length of the fragmented file is very short, the client can quickly select and switch the bitrate to adapt to different bandwidth conditions of playback. Apple has taken a tough line on its own HLS promotion, and when your live content lasts for 10 minutes or more than 5 MB every five minutes, your APP Live service must be in HLS architecture, otherwise it won't be allowed to shelves.
Service SupportAdobe Flash Media Server: Supports HLS, Protected HLS (PHLS) starting from 4.5. 5.0 renamed Adobe Media serverrealnetworks Helix Universal server:2010 April, version 15.0 started to support HTTP live, on-demand h.264/for iphone, ipad and ipod AAC content, last updated on November 2012. Microsoft's IIS Media Services: Supports HLS from 4.0 onwards. Nginx RTMP Module: HLS that supports live mode. VLC Media Player: Supports live and on-demand HLS from 2.0 onwards. Wowza Media server:2009 December 9 Release 2.0, began full support HLS. Vodobox Live Server: HLS is supported.
Client Support Environment
Native support
Android 3.0+ios 3.0+
Flash Support:Adobe Flash Player supports HLS from 11.0 onwards. mediaelement.js (MIT)
FlowPlayer (GPLX) grindplayer (MIT) video-js-swf (Apache License 2.0) clappr (BSD ie10+x)
The Windows 10 EDGE browser starts to support HLS.
From for notes (Wiz)
Live on-demand HLS based on HTTP
