Shaka Player supports offline playback since v1.3.0. Offline streams are handled by {@link shaka.player.OfflineVideoSource}. The offline API works similarily to the other video source APIs, but adds the functionality to store a group, retrieve a list of all stored groups and to delete a group from storage.
A group refers to one video stream and one audio stream, if present, from a DASH MPD. Storage of text content is not yet supported. Each group will have a unique ID, which should be persisted by the application for later playback.
If you have not familiarized yourself with the the Player, please start with {@tutorial player}. In order to store content you need to install the polyfills and initialize the player, but do not need to load the video source.
Here is a simple page which demonstrates basic offline storage:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>TurtleTube - Offline</title>
<!-- Load the Shaka Player library. -->
<script src="shaka-player.compiled.js"></script>
</head>
<body>
<video id="video"
width="640" height="480"
crossorigin="anonymous"
controls>
Your browser does not support HTML5 video.
</video>
</body>
<script>
var video;
function initPlayer() {
// Install polyfills.
shaka.polyfill.installAll();
// Find the video element.
video = document.getElementById('video');
// Attach the player to the window so that it can be easily debugged.
window.player = new shaka.player.Player(video);
// Listen for errors from the Player.
player.addEventListener('error', function(event) {
console.error(event);
});
}
function initialize() {
if (!window.player)
initPlayer();
}
function chooseTracks(videoSource) {
var ids = [];
var videoTracks = videoSource.getVideoTracks();
if (videoTracks.length) {
videoTracks.sort(shaka.player.VideoTrack.compare);
// Choosing the smallest track.
var track = videoTracks[0];
ids.push(track.id);
}
var audioTracks = videoSource.getAudioTracks();
if (audioTracks.length) {
// The video source gives you the preferred language first.
// Remove any tracks from other languages first.
var lang = audioTracks[0].lang;
audioTracks = audioTracks.filter(function(track) {
return track.lang == lang;
});
// From what's left, choose the middle stream. If we have high, medium,
// and low quality audio, this is medium. If we only have high and low,
// this is high.
var index = Math.floor(audioTracks.length / 2);
ids.push(audioTracks[index].id);
}
// Return IDs of chosen tracks.
return Promise.resolve(ids);
}
function storeContent() {
// Construct an OfflineVideoSource.
var offlineSource = new shaka.player.OfflineVideoSource(
null, // groupId, not used when storing content.
null); // estimator, optional parameter.
// Listen for progress events from the OfflineVideoSource.
offlineSource.addEventListener('progress', function(event) {
// Percentage complete is the detail field of the event.
console.log(
'Content storage is ' + event.detail.toFixed(2) + '% complete.');
});
// Store content from MPD url.
var mpdUrl = 'https://turtle-tube.appspot.com/t/t2/dash.mpd';
var preferredLanguage = 'en-US';
return offlineSource.store(
mpdUrl,
preferredLanguage,
null, // interpretContentProtection, not needed for clear content.
chooseTracks.bind(null, offlineSource)
).then(
function(groupId) {
window.groupId = groupId;
console.log('Stored content under group ID ' + groupId);
}
);
}
function test() {
initialize();
storeContent().catch(
function(e) {
console.error(e);
});
}
document.addEventListener('DOMContentLoaded', test);
</script>
</html>
In order to playback content, you need the group ID of the stored content. The group ID will be used to create a new {@link shaka.player.OfflineVideoSource} to be loaded into the {@link shaka.player.Player}.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>TurtleTube - Offline</title>
<!-- Load the Shaka Player library. -->
<script src="shaka-player.compiled.js"></script>
</head>
<body>
<video id="video"
width="640" height="480"
crossorigin="anonymous"
controls>
Your browser does not support HTML5 video.
</video>
</body>
<script>
var video;
function initPlayer() {
// Install polyfills.
shaka.polyfill.installAll();
// Find the video element.
video = document.getElementById('video');
// Attach the player to the window so that it can be easily debugged.
window.player = new shaka.player.Player(video);
// Listen for errors from the Player.
player.addEventListener('error', function(event) {
console.error(event);
});
}
function initialize() {
if (!window.player)
initPlayer();
}
function chooseTracks(videoSource) {
var ids = [];
var videoTracks = videoSource.getVideoTracks();
if (videoTracks.length) {
videoTracks.sort(shaka.player.VideoTrack.compare);
// Choosing the smallest track.
var track = videoTracks[0];
ids.push(track.id);
}
var audioTracks = videoSource.getAudioTracks();
if (audioTracks.length) {
// The video source gives you the preferred language first.
// Remove any tracks from other languages first.
var lang = audioTracks[0].lang;
audioTracks = audioTracks.filter(function(track) {
return track.lang == lang;
});
// From what's left, choose the middle stream. If we have high, medium,
// and low quality audio, this is medium. If we only have high and low,
// this is high.
var index = Math.floor(audioTracks.length / 2);
ids.push(audioTracks[index].id);
}
// Return IDs of chosen tracks.
return Promise.resolve(ids);
}
function storeContent() {
// Construct an OfflineVideoSource.
var offlineSource = new shaka.player.OfflineVideoSource(
null, // groupId, not used when storing content.
null); // estimator, optional parameter.
// Listen for progress events from the OfflineVideoSource.
offlineSource.addEventListener('progress', function(event) {
// Percentage complete is the detail field of the event.
console.log(
'Content storage is ' + event.detail.toFixed(2) + '% complete.');
});
// Store content from MPD url.
var mpdUrl = 'https://turtle-tube.appspot.com/t/t2/dash.mpd';
var preferredLanguage = 'en-US';
return offlineSource.store(
mpdUrl,
preferredLanguage,
null, // interpretContentProtection, not needed for clear content.
chooseTracks.bind(null, offlineSource)
).then(
function(groupId) {
window.groupId = groupId;
console.log('Stored content under group ID ' + groupId);
}
);
}
function playOfflineContent() {
// Construct an OfflineVideoSource and load with player.
var offlineSource =
new shaka.player.OfflineVideoSource(window.groupId, null);
return window.player.load(offlineSource).then(
function() {
video.play();
console.log('Offline content with group ID ' + window.groupId +
' ready for playback.');
});
}
function test() {
initialize();
storeContent().then(playOfflineContent).catch(
function(e) {
console.error(e);
});
}
document.addEventListener('DOMContentLoaded', test);
</script>
</html>
Similar to playing stored content, you will create a new {@link shaka.player.OfflineVideoSource} with a known group ID to delete content.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>TurtleTube - Offline</title>
<!-- Load the Shaka Player library. -->
<script src="shaka-player.compiled.js"></script>
</head>
<body>
<video id="video"
width="640" height="480"
crossorigin="anonymous"
controls>
Your browser does not support HTML5 video.
</video>
</body>
<script>
var video;
function initPlayer() {
// Install polyfills.
shaka.polyfill.installAll();
// Find the video element.
video = document.getElementById('video');
// Attach the player to the window so that it can be easily debugged.
window.player = new shaka.player.Player(video);
// Listen for errors from the Player.
player.addEventListener('error', function(event) {
console.error(event);
});
}
function initialize() {
if (!window.player)
initPlayer();
}
function chooseTracks(videoSource) {
var ids = [];
var videoTracks = videoSource.getVideoTracks();
if (videoTracks.length) {
videoTracks.sort(shaka.player.VideoTrack.compare);
// Choosing the smallest track.
var track = videoTracks[0];
ids.push(track.id);
}
var audioTracks = videoSource.getAudioTracks();
if (audioTracks.length) {
// The video source gives you the preferred language first.
// Remove any tracks from other languages first.
var lang = audioTracks[0].lang;
audioTracks = audioTracks.filter(function(track) {
return track.lang == lang;
});
// From what's left, choose the middle stream. If we have high, medium,
// and low quality audio, this is medium. If we only have high and low,
// this is high.
var index = Math.floor(audioTracks.length / 2);
ids.push(audioTracks[index].id);
}
// Return IDs of chosen tracks.
return Promise.resolve(ids);
}
function storeContent() {
// Construct an OfflineVideoSource.
var offlineSource = new shaka.player.OfflineVideoSource(
null, // groupId, not used when storing content.
null); // estimator, optional parameter.
// Listen for progress events from the OfflineVideoSource.
offlineSource.addEventListener('progress', function(event) {
// Percentage complete is the detail field of the event.
console.log(
'Content storage is ' + event.detail.toFixed(2) + '% complete.');
});
// Store content from MPD url.
var mpdUrl = 'https://turtle-tube.appspot.com/t/t2/dash.mpd';
var preferredLanguage = 'en-US';
return offlineSource.store(
mpdUrl,
preferredLanguage,
null, // interpretContentProtection, not needed for clear content.
chooseTracks.bind(null, offlineSource)
).then(
function(groupId) {
window.groupId = groupId;
console.log('Stored content under group ID ' + groupId);
}
);
}
function playOfflineContent() {
// Construct an OfflineVideoSource and load with player.
var offlineSource =
new shaka.player.OfflineVideoSource(window.groupId, null);
return window.player.load(offlineSource).then(
function() {
video.play();
console.log('Offline content with group ID ' + window.groupId +
' ready for playback.');
});
}
function deleteOfflineContent() {
var offlineSource =
new shaka.player.OfflineVideoSource(window.groupId, null);
return offlineSource.deleteGroup().then(
function() {
console.log('Offline content with group ID ' + window.groupId +
' successfully deleted.');
});
}
function test() {
initialize();
storeContent().then(deleteOfflineContent).catch(
function(e) {
console.error(e);
});
}
document.addEventListener('DOMContentLoaded', test);
</script>
</html>
{@link shaka.player.OfflineVideoSource} can only store encrypted streams on platforms that support persistent licenses.
Offline playback relies on the {@link http://goo.gl/TFHaXL Indexed Database API} for storage of content. Indexed Database is currently supported by most web browsers.