Chromecast (Standalone)

The Google Cast framework enables a viewer to stream video and audio content to a compatible TV or sound system. By enabling the Google Cast framework in your app, a viewer can use a cast button to stream your content to a Cast-enabled device on a shared network connection.

Basic setup

In order to stream DRM-protected content on a Cast-enabled device, you must create a Cast app. The Cast app consists of two parts: a Sender app and a Receiver app.

The Sender app is part of either the web page or your chosen player that sets up the load function.

load(url, token, laUrl) {
    if (player.isConnected) { return };
    let mediaInfo = new chrome.cast.media.MediaInfo(url);
    mediaInfo.metadata = new chrome.cast.media.GenericMediaMetadata();
    mediaInfo.metadata.metadataType = chrome.cast.media.MetadataType.GENERIC;
    mediaInfo.metadata.title = 'Studio DRM Demo';
    mediaInfo.customData = { laUrl, token };

    let request = new chrome.cast.media.LoadRequest(mediaInfo);
    request.autoplay = true;
    request.currentTime = 0;
    cast.framework.CastContext.getInstance().getCurrentSession().loadMedia(request).catch((error) => {
        console.error(error);
    });
}

The Receiver app is hosted by you, must be registered with Google, and manages the communication between the Sender app and the Cast device.

let videoElement = document.getElementById("your-video-element");
if (event.data.media && event.data.media.contentId){
    let url = event.data.media.contentId;
    let initStart = event.data.media.currentTime || 0;
    let autoplay = !!event.data.autoplay;
    let customData = event.data.media.customData || {};

    let host = new cast.player.api.Host({mediaElement:videoElement, url});
    let protocol = cast.player.api.CreateDashStreamingProtocol(host);
    let player = new cast.player.api.Player(host);
    player.load(protocol, initStart);
    host.onError = (errorCode) => {
        console.error('Fatal Error ' + errorCode);
        if (player) {
            player.unload();
            player = null;
        }
    }

MPEG-DASH overrides

host.protectionSystem = cast.player.api.ContentProtection.WIDEVINE;
host.licenseUrl = 'https://widevine-license.vudrm.tech/proxy';

host.processManifest = (manifest) => {
    let parser = new DOMParser();
    let xmlDoc = parser.parseFromString(manifest, 'text/xml');
    let el = xmlDoc.querySelector('ContentProtection');
    let kid = el ? el.getAttribute('cenc:default_KID') : '';
    return manifest;
};

host.updateLicenseRequestInfo = (requestInfo) => {
    // customData is the message object that was sent to the receiver.
    let body = JSON.stringify({
        token: customData.token,
        drm_info: Array.apply(null, requestInfo.content),
        kid: kid
    });

    let buffer = [];

    for (let i=0; i<body.length; i++) {
        buffer.push(body.charCodeAt(i));
    }

    requestInfo.headers['Content-Type'] = 'application/json';
    requestInfo.content = new Uint8Array(buffer);
}

protocol = cast.player.api.CreateDashStreamingProtocol(host);