videojs-contrib-quality-levels

What is videojs-contrib-quality-levels?

The videojs-contrib-quality-levels package is a plugin for Video.js that provides an API for managing and interacting with the quality levels of a video. This is particularly useful for adaptive bitrate streaming, where multiple quality levels are available, and you want to control or monitor which quality level is being used.

What are videojs-contrib-quality-levels's main functionalities?

Get Available Quality Levels

This feature allows you to get all available quality levels for the video. The 'addqualitylevel' event is triggered whenever a new quality level is added, and you can access the quality level object from the event.

const player = videojs('my-video');
player.qualityLevels().on('addqualitylevel', function(event) {
  const qualityLevel = event.qualityLevel;
  console.log('Quality level added:', qualityLevel);
});

Select a Quality Level

This feature allows you to select a specific quality level based on certain criteria, such as resolution. In this example, the code selects the 720p quality level and disables all others.

const player = videojs('my-video');
const qualityLevels = player.qualityLevels();
qualityLevels.on('addqualitylevel', function(event) {
  const qualityLevel = event.qualityLevel;
  if (qualityLevel.height === 720) { // Select 720p quality level
    qualityLevel.enabled = true;
  } else {
    qualityLevel.enabled = false;
  }
});

Monitor Quality Level Changes

This feature allows you to monitor changes in the active quality level. The 'change' event is triggered whenever the active quality level changes, and you can access the new active quality level from the qualityLevels array.

const player = videojs('my-video');
const qualityLevels = player.qualityLevels();
qualityLevels.on('change', function() {
  const activeQualityLevel = qualityLevels[qualityLevels.selectedIndex];
  console.log('Active quality level changed to:', activeQualityLevel);
});

Other packages similar to videojs-contrib-quality-levels

videojs-http-source-selector

The videojs-http-source-selector plugin provides a UI component for selecting different quality levels in a Video.js player. It adds a button to the control bar that allows users to manually select the desired quality level. Unlike videojs-contrib-quality-levels, which focuses on providing an API for managing quality levels, videojs-http-source-selector provides a user interface for manual selection.

videojs-hls-quality-selector

The videojs-hls-quality-selector plugin is another Video.js plugin that adds a quality selector menu to the player. It is specifically designed for HLS (HTTP Live Streaming) and allows users to manually select the desired quality level from a dropdown menu. This plugin is similar to videojs-http-source-selector but is tailored for HLS streams.

videojs-resolution-switcher

The videojs-resolution-switcher plugin allows users to switch between different video resolutions manually. It adds a button to the Video.js control bar that lets users choose from available resolutions. This plugin is similar to videojs-contrib-quality-levels in that it deals with multiple quality levels, but it focuses more on providing a user interface for manual resolution switching.

README

videojs-contrib-quality-levels

Exposes a list of quality levels available for the source.

Table of Contents

Installation

npm install --save videojs-contrib-quality-levels

The npm installation is preferred, but Bower works, too.

bower install  --save videojs-contrib-quality-levels

Using

The list of QualiyLevels can be accessed using qualityLevels() on the Player object. With this list, you can:

• see which quality levels are available for the current source
• enable or disable specific quality levels to change which levels are selected by ABR
• see which quality level is currently selected by ABR

Example

let player = videojs('my-video');

let qualityLevels = player.qualityLevels();

// disable quality levels with less than 720 horizontal lines of resolution when added
// to the list.
qualityLevels.on('addqualitylevel', function(event) {
  let qualityLevel = event.qualityLevel;

  if (qualityLevel.height >= 720) {
    qualityLevel.enabled = true;
  } else {
    qualityLevel.enabled = false;
  }
});

// example function that will toggle quality levels between SD and HD, defining and HD
// quality as having 720 horizontal lines of resolution or more
let toggleQuality = (function() {
  let enable720 = true;

  return function() {
    for (var i = 0; i < qualityLevels.length; i++) {
      let qualityLevel = qualityLevels[i];
      if (qualityLevel.width >= 720) {
        qualityLevel.enabled = enable720;
      } else {
        qualityLevel.enabled = !enable720;
      }
    }
    enable720 = !enable720;
  };
})();

let currentSelectedQualityLevelIndex = qualityLevels.selectedIndex; // -1 if no level selected

Populating the list

Initially the list of quality levels will be empty. You can add quality levels to the list by using QualityLevelList.addQualityLevel for each quality level specific to your source. QualityLevelList.addQualityLevel takes in a Representation object (or generic object with the required properties). All properties are required except width and height.

Example Representation

Representation {
  id: string,
  width: number,
  height: number,
  bitrate: number,
  enabled: function
}

The enabled function should take an optional boolean to enable or disable the representation and return whether it is currently enabled.

HLS

Quality levels for an HLS source will be automatically populated when using videojs-contrib-hls version 4.1 or greater.

Including the Plugin

To include videojs-contrib-quality-levels on your website or web application, use any of the following methods.

<script> Tag

This is the simplest case. Get the script in whatever way you prefer and include the plugin after you include video.js, so that the videojs global is available.

<script src="//path/to/video.min.js"></script>
<script src="//path/to/videojs-contrib-quality-levels.min.js"></script>
<script>
  var player = videojs('my-video');

  player.qualityLevels();
</script>

Browserify

When using with Browserify, install videojs-contrib-quality-levels via npm and require the plugin as you would any other module.

var videojs = require('video.js');

// The actual plugin function is exported by this module, but it is also
// attached to the `Player.prototype`; so, there is no need to assign it
// to a variable.
require('videojs-contrib-quality-levels');

var player = videojs('my-video');

player.qualityLevels();

RequireJS/AMD

When using with RequireJS (or another AMD library), get the script in whatever way you prefer and require the plugin as you normally would:

require(['video.js', 'videojs-contrib-quality-levels'], function(videojs) {
  var player = videojs('my-video');

  player.qualityLevels();
});

License

Apache-2.0. Copyright (c) Brightcove, Inc.

Changelog

2.0.4 (2018-01-22)

• Allow video js 6 to be used (#25)