Radiant Media Player

HLS streaming (hls.js) - Radiant Media Player

Documentation sections

HLS support in Radiant Media Player

Radiant Media Player provides a comprehensive and cross-device solution to display HLS streams for on-demand, live or DVR content. Our HLS to HTML5 video implementation relies on media source extensions (MSE) and is based on hls.js. Where media source extensions are not available (e.g. iOS, macOS Safari, older Android) we fallback to native HLS to HTML5 video. When neither media source extensions nor native HLS support are available the player may fallback to HLS to Flash. Note that Flash support in Radiant Media Player is deprecated and limited to supporting HLS streaming to Internet Explorer 11 for Windows 7.

A standard-compliant HLS streaming URL is all you need - the player will take care of opting for the best way to render it based on device capabilities.

Supported HLS features

  • Playback of H.264 + AAC or H.264 + MP3 content in .ts fragments
  • Playback of H.264 + AAC in fmp4 fragments (fragmented MP4 container)
  • Playback of H.265 (HEVC) + AAC in fmp4 fragments (fragmented MP4 container) where supported
  • Live, DVR and on-demand video streaming
  • Optimized adaptive bitrate streaming with automatic or manual bitrate selection
  • Multiple-audio tracks
  • AES-128/SAMPLE-AES decryption
  • ID3 tags
  • WebVTT & CEA 608/708 captions
  • Program-date-time
  • Discontinuities
  • Resilience to errors
  • Redundant/Failover Playlists
  • Audio-only: AAC container or MPEG Audio container (MPEG-1/2 Audio Layer III)
  • App-store compliant HLS streams playback (see hlsJSAppleAppStoreCompliance setting below for compliance notes)

Generally available features like video ads, JavaScript API or playback rate changes are also supported with HLS to Radiant Media Player.

Supported M3U8 tags

  • #EXTM3U
  • #EXT-X-STREAM-INF (adaptive streaming)
  • #EXT-X-ENDLIST (Live playlist)
  • #EXT-X-MAP
  • #EXT-X-KEY

Supported environments

See our compatibility table for a list of environments where HLS streaming is supported with Radiant Media Player.

Best practices

As a rule of thumb Radiant Media Player should work with any-standard compliant HLS streaming service provider. In order to provide better cross-device support for HLS streaming to Radiant Media Player we recommend the following:

  • You must set up your streaming server to return proper CORS settings permitting GET requests.
  • For H.264 encoded content H.264 Main profile provides best coverage - H.264 Level 5+ (this is for 4K/360 content mainly) encoded content may cause playback issue on older devices so only go there if you need to.
  • Have the same pair of video/audio codecs for each rendition of the HLS stream.
  • Have the same audio sampling rate and number of audio channels for each rendition of the HLS stream.
  • For HLS with .ts segments, .ts segments should be 10 seconds length whenever possible.

Player code example

In this example we use a multi-bitrate HLS (.ts with H.264/AAC) stream:

<!-- Include Radiant Media Player JavaScript file in your <body> or <head> -->
<script src="https://cdn.radiantmediatechs.com/rmp/4.6.31/js/rmp.min.js" 
<!-- Set up your wrapper div with its unique id -->
<div id="rmpPlayer"></div>
<!-- Set up player configuration options -->
// Here we set our HLS streaming URL
var bitrates = {
  hls: 'https://dqwp3xzzbfhtw.cloudfront.net/vod/smil:bbb.smil/playlist.m3u8'
var settings = {
  licenseKey: 'your-license-key',
  bitrates: bitrates,
  width: 640,
  height: 360,
  poster: 'https://www.radiantmediaplayer.com/images/poster-rmp-showcase.jpg'
// Reference to the wrapper div (unique id)
var elementID = 'rmpPlayer';
// Create an object based on RadiantMP constructor
var rmp = new RadiantMP(elementID);
// Initialization ... test your page and done!

Native HLS support notes

On iOS & macOS Safari and older Android devices (Android before version 5), we display HLS to HTML5 video using native device support (this is where media source extensions are not available or not reliable enough). On those devices limitations may apply:

  • DVR controls may not be supported, in which case DVR streams will be treated as simple live streams - on iOS 11+ DVR controls are only available in fullscreen mode
  • Manual bitrate switching is not supported - the player uses adaptive bitrate streaming in auto mode and the adaptation logic is left to the device
  • ID3 tags & program-date-time are managed internally and may not be accessible through our API
  • In iOS fullscreen mode the player will be displayed using the native iOS player (QuickTime-based)

HLS player settings

hlsJSCapLevelToPlayerSize: Boolean

This setting limits bitrates usable in auto-quality depending on player size (width & height). Default: true. If set to true, width and height (defined in m3u8 playlist) will be compared with the actual player width and height and only the best match will be used as the maximum available bitrate, hence helping to preserve bandwidth usage while maintaining streaming quality. This setting is ignored in manual mode so all levels can be selected manually. Note that this setting takes into account information provided by window.devicePixelRatio to preserve quality on mobile devices. For 360 video this setting is always set to false.

hlsJSStopDownloadWhilePaused: Boolean

When set to true this setting will cause the player to stop downloading HLS fragments while it is in a paused or stopped state. This can help to preserve bandwidth. Default: false.

hlsJSEnableCaptions: Boolean
This setting indicates to the player whether or not to parse and display CEA 608/708 or WebVTT captions when detected in an HLS stream. Default: true.
hlsJSLiveSyncDuration: Number
Edge of live delay, expressed in seconds. Default: 30. A value too low (inferior to ~3 segment durations) is likely to cause playback stalls.
hlsJSAppleAppStoreCompliance: Boolean
For App-store compliant HLS video streams which include an audio-only rendition this setting should be set to true to insure proper playback across devices. Default: false.
hlsJSMaxAudioFramesDrift: Number
See here for full details on this setting. You generally do not need to tweak this setting unless trying to solve specific audio issues with some exotic HLS streams. Default: 1.
hlsJSDefaultAudioCodec: String
If audio codec is not signaled in variant manifest, or if only a stream manifest is provided, the player will try to guess audio codec by parsing audio sampling rate in ADTS header. If sampling rate is less or equal than 22050 Hz, then the player assumes it is HE-AAC, otherwise it assumes it is AAC-LC. This could result in bad guess, leading to audio decode error, ending up in media error. It is possible to hint default audio codec to the player by setting hlsJSDefaultAudioCodec to:
  • 'mp4a.40.2': AAC-LC
  • 'mp4a.40.5': HE-AAC
  • 'auto': the player auto-guesses. This is the default.
hlsJSXhrWithCredentials: Boolean
This setting indicates to the player whether or not cross-site Access-Control requests should be made using credentials such as cookies, authorization headers or TLS client certificates. Setting withCredentials has no effect on same-site requests. Default: false.
hlsJSUseManifestRenditionName: Boolean
By default the player present renditions in the quality menu as "resolution · bitrate" pattern. Example: 400p · 1728 kbps. However a HLS manifest is also required to have a NAME attribute for each rendition. When set to true this setting will cause the player to display the NAME of the rendition in place of the "resolution · bitrate" default pattern. Default: false.
hlsJSLight: Boolean
hls.js offers a lighter and faster option to render HLS content through hls.light.js. However the hls.light.js file does not allow to display multi-audio or captions tracks. If you are sure you do not need multi-audio tracks or captions tracks support then you can set hlsJSLight to true to benefit from a slight performance boost when streaming with HLS and hls.js. Default: false.
hlsJSXhrSetup: Function
This setting allows to pass a custom XMLHttpRequest setup to the player (including passing custom HTTP headers). This custom XMLHttpRequest setup will be used for all HLS playlist/chunk requests. Following is an example of using this feature. Note this is just an example - you will need to adapt this to your own set up for a working solution.
function xhrSetup(xhr) {
  if (xhr) {
    // passing custom headers
    xhr.setRequestHeader('X-File-Name', 'rmp-file');
    // passing cookies withCredentials
    xhr.withCredentials = true;
// Then we set our player settings
var settings = {
  licenseKey: 'your-license-key',
  bitrates: {
    hls: 'your-hls-url'
  width: 640,
  height: 360,
  hlsJSXhrSetup: xhrSetup
hlsWithMp3Audio: Boolean

When set to true the player will provide support for HLS video with H.264/MP3 in MPEG-2 TS container or HLS audio-only in MPEG Audio container (MPEG-1/2 Audio Layer III audio only streams). Note that Microsoft-based browsers (MS Edge or IE 11) do not currently support audio-only HLS in MPEG Audio container so an MP3 progressive download fallback is recommended to support those browsers. Default: false.

forceHlsJSOnMacOSSafari: Boolean

When set to true the player will force use hls.js on macOS Safari (where native HLS would be used generally). The main use case is to enable DVR controls on macOS Safari. Note that hls.js support for macOS Safari is still in BETA as of October 2017 so only use this setting if you have a business requirement to do so. Also note that setting forceHlsJSOnMacOSSafari to true disables AirPlay casting support from macOS Safari as it requires native HLS or MP4 progressive download. Default: false. When forceHlsJSOnMacOSSafari is set to true the only option to display vide ads is the IMA SDK and AirPlay will not be available.

hlsEngine: String

Since Radiant Media Player 4.4.0 it is possible to use Shaka Player HLS streaming engine instead of hls.js. While hls.js offers more options using HLS through Shaka player notably provides support for HLS with DRM content. Default: 'hlsjs'. Other possible value is 'shakaplayer'.

hlsJSCustomConfig: Object

Allow passing a custom config object to hls.js. As such any hls.js internal setting can be tuned. Note that this may override any setting previously documented on this page. Default: {}. Example:

var hlsJSCustomConfig = {
  fragLoadingTimeOut: 20000,
  fragLoadingMaxRetry: 6,
  fragLoadingRetryDelay: 500,
  fragLoadingMaxRetryTimeout: 64000
var settings = {
  licenseKey: 'your-license-key',
  bitrates: {
    hls: 'your-hls-url'
  width: 640,
  height: 360,
  hlsJSCustomConfig: hlsJSCustomConfig

See this page for a list of all hls.js options.

useNativeHlsOverMseHls: Boolean

This setting forces the player to opt for native HLS to HTML5 video (where supported by the targeted device) when both native HLS and MSE HLS (through hls.js or Shaka Player) are available. Default: false.

hls.js ABR & buffer player settings

HLS is an adaptive bitrate streaming technology. Hence having a well-tuned ABR logic is paramount to insure a good user experience and reduce bandwidth cost. Radiant Media Player default ABR logic is tuned to work well in most common use-cases seen now-days. The following settings will let you tune the ABR/buffer logic to your environment. Only use those settings if you are trying to address a specific issue and fully understand what they do. Ill-configured ABR/buffer settings may cause a deteriorated user experience. Those settings are only applicable when streaming HLS through hls.js in Radiant Media Player, they do not apply when using native HLS or HLS through Shaka player (ABR/buffer settings for Shaka player are available here).

Also note that the player offers a getHlsBwEstimate API method that allows to track in real-time the available device bandwidth captured by the player (only applies to hls.js).

hlsJSMaxBufferLength: Number

Maximum buffer length in seconds. The player will try to reach and never exceed this value for its internal buffer. Default: 30.

hlsJSStartLevel: Number
Defines the preferred initial bitrate when playback starts. Default: -1.
  • -1: automatic start level selection, playback will start from level matching download bandwidth (determined from download of first segment).
  • 0: first level appearing in manifest will be used as start level.
  • n: where n is an integer will cause the player to select the n th level at startup (based on the order of appearance in the manifest). Note that index starts at 0 - so if you have a playlist with 4 levels and you want to start with the 3rd appearing level, n should be 2.
Best practice: when hlsJSStartLevel is set to -1, your HLS manifest should include a lower-end rendition (generally this should not exceed 500 kbps audio & video included) and this rendition should be the first listed in your HLS manifest. As such the player will base its initial bandwidth calculation based on this level and this should provide optimal performance.
hlsJSAbrDefaultBandwidthEstimate: Number

Default bandwidth estimate in bits/second prior to collecting fragment bandwidth samples. Default: 500000.

hlsJSMinAutoBitrate: Number
Set the minimum value (in bps) that should be used by the ABR algorithm. Default: 0. For example setting hlsJSMinAutoBitrate to 500000 means that the player - while in auto mode - will pick the best matching level that has a bitrate above or equal to 500000 bps (500 kbps).
hlsJSAbrBandWidthFactor: Number
Scale factor to be applied against measured bandwidth average, to determine whether we can stay on current or lower quality level. If hlsJSAbrBandWidthFactor * bandwidth average < level.bitrate then ABR can switch to that level providing that it is equal or less than current level. Default: 0.95.
hlsJSAbrBandWidthUpFactor: Number
Scale factor to be applied against measured bandwidth average, to determine whether we can switch up to a higher quality level. If hlsJSAbrBandWidthUpFactor * bandwidth average < level.bitrate then ABR can switch up to that quality level. Default: 0.75.
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