/**
* @license
* Copyright 2016 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
goog.provide('shaka.util.StreamUtils');
goog.require('goog.asserts');
goog.require('shaka.log');
goog.require('shaka.media.DrmEngine');
goog.require('shaka.media.MediaSourceEngine');
goog.require('shaka.text.TextEngine');
goog.require('shaka.util.Functional');
goog.require('shaka.util.LanguageUtils');
goog.require('shaka.util.ManifestParserUtils');
goog.require('shaka.util.MimeUtils');
/**
* @namespace shaka.util.StreamUtils
* @summary A set of utility functions for dealing with Streams and Manifests.
*/
/**
* @param {shaka.extern.Variant} variant
* @param {shaka.extern.Restrictions} restrictions
* Configured restrictions from the user.
* @param {{width: number, height: number}} maxHwRes
* The maximum resolution the hardware can handle.
* This is applied separately from user restrictions because the setting
* should not be easily replaced by the user's configuration.
* @return {boolean}
*/
shaka.util.StreamUtils.meetsRestrictions = function(
variant, restrictions, maxHwRes) {
/** @type {function(number, number, number):boolean} */
const inRange = (x, min, max) => {
return x >= min && x <= max;
};
const video = variant.video;
// |video.width| and |video.height| can be undefined, which breaks
// the math, so make sure they are there first.
if (video && video.width && video.height) {
if (!inRange(video.width,
restrictions.minWidth,
Math.min(restrictions.maxWidth, maxHwRes.width))) {
return false;
}
if (!inRange(video.height,
restrictions.minHeight,
Math.min(restrictions.maxHeight, maxHwRes.height))) {
return false;
}
if (!inRange(video.width * video.height,
restrictions.minPixels,
restrictions.maxPixels)) {
return false;
}
}
if (!inRange(variant.bandwidth,
restrictions.minBandwidth,
restrictions.maxBandwidth)) {
return false;
}
return true;
};
/**
* @param {!Array.<shaka.extern.Variant>} variants
* @param {shaka.extern.Restrictions} restrictions
* @param {{width: number, height: number}} maxHwRes
* @return {boolean} Whether the tracks changed.
*/
shaka.util.StreamUtils.applyRestrictions =
function(variants, restrictions, maxHwRes) {
let tracksChanged = false;
variants.forEach((variant) => {
let originalAllowed = variant.allowedByApplication;
variant.allowedByApplication = shaka.util.StreamUtils.meetsRestrictions(
variant, restrictions, maxHwRes);
if (originalAllowed != variant.allowedByApplication) {
tracksChanged = true;
}
});
return tracksChanged;
};
/**
* Alters the given Period to filter out any unplayable streams.
*
* @param {shaka.media.DrmEngine} drmEngine
* @param {?shaka.extern.Stream} activeAudio
* @param {?shaka.extern.Stream} activeVideo
* @param {shaka.extern.Period} period
*/
shaka.util.StreamUtils.filterNewPeriod = function(
drmEngine, activeAudio, activeVideo, period) {
const StreamUtils = shaka.util.StreamUtils;
if (activeAudio) {
goog.asserts.assert(StreamUtils.isAudio(activeAudio),
'Audio streams must have the audio type.');
}
if (activeVideo) {
goog.asserts.assert(StreamUtils.isVideo(activeVideo),
'Video streams must have the video type.');
}
// Filter variants.
period.variants = period.variants.filter((variant) => {
if (drmEngine && drmEngine.initialized()) {
if (!drmEngine.supportsVariant(variant)) {
shaka.log.debug('Dropping variant - not compatible with key system',
variant);
return false;
}
}
const audio = variant.audio;
const video = variant.video;
if (audio && !shaka.media.MediaSourceEngine.isStreamSupported(audio)) {
shaka.log.debug('Dropping variant - audio not compatible with platform',
StreamUtils.getStreamSummaryString_(audio));
return false;
}
if (video && !shaka.media.MediaSourceEngine.isStreamSupported(video)) {
shaka.log.debug('Dropping variant - video not compatible with platform',
StreamUtils.getStreamSummaryString_(video));
return false;
}
if (audio && activeAudio) {
if (!StreamUtils.areStreamsCompatible_(audio, activeAudio)) {
shaka.log.debug('Droping variant - not compatible with active audio',
'active audio',
StreamUtils.getStreamSummaryString_(activeAudio),
'variant.audio',
StreamUtils.getStreamSummaryString_(audio));
return false;
}
}
if (video && activeVideo) {
if (!StreamUtils.areStreamsCompatible_(video, activeVideo)) {
shaka.log.debug('Droping variant - not compatible with active video',
'active video',
StreamUtils.getStreamSummaryString_(activeVideo),
'variant.video',
StreamUtils.getStreamSummaryString_(video));
return false;
}
}
return true;
});
// Filter text streams.
period.textStreams = period.textStreams.filter(function(stream) {
let fullMimeType = shaka.util.MimeUtils.getFullType(
stream.mimeType, stream.codecs);
let keep = shaka.text.TextEngine.isTypeSupported(fullMimeType);
if (!keep) {
shaka.log.debug('Dropping text stream. Is not supported by the ' +
'platform.', stream);
}
return keep;
});
};
/**
* @param {shaka.extern.Stream} s0
* @param {shaka.extern.Stream} s1
* @return {boolean}
* @private
*/
shaka.util.StreamUtils.areStreamsCompatible_ = function(s0, s1) {
// Basic mime types and basic codecs need to match.
// For example, we can't adapt between WebM and MP4,
// nor can we adapt between mp4a.* to ec-3.
// We can switch between text types on the fly,
// so don't run this check on text.
if (s0.mimeType != s1.mimeType) {
return false;
}
if (s0.codecs.split('.')[0] != s1.codecs.split('.')[0]) {
return false;
}
return true;
};
/**
* @param {shaka.extern.Variant} variant
* @return {shaka.extern.Track}
*/
shaka.util.StreamUtils.variantToTrack = function(variant) {
/** @type {?shaka.extern.Stream} */
let audio = variant.audio;
/** @type {?shaka.extern.Stream} */
let video = variant.video;
/** @type {?string} */
let audioCodec = audio ? audio.codecs : null;
/** @type {?string} */
let videoCodec = video ? video.codecs : null;
/** @type {!Array.<string>} */
let codecs = [];
if (videoCodec) codecs.push(videoCodec);
if (audioCodec) codecs.push(audioCodec);
/** @type {!Array.<string>} */
let mimeTypes = [];
if (video) mimeTypes.push(video.mimeType);
if (audio) mimeTypes.push(audio.mimeType);
/** @type {?string} */
let mimeType = mimeTypes[0] || null;
/** @type {!Array.<string>} */
let kinds = [];
if (audio) kinds.push(audio.kind);
if (video) kinds.push(video.kind);
/** @type {?string} */
let kind = kinds[0] || null;
/** @type {!Set.<string>} */
const roles = new Set();
if (audio) audio.roles.forEach((role) => roles.add(role));
if (video) video.roles.forEach((role) => roles.add(role));
/** @type {shaka.extern.Track} */
let track = {
id: variant.id,
active: false,
type: 'variant',
bandwidth: variant.bandwidth,
language: variant.language,
label: null,
kind: kind,
width: null,
height: null,
frameRate: null,
mimeType: mimeType,
codecs: codecs.join(', '),
audioCodec: audioCodec,
videoCodec: videoCodec,
primary: variant.primary,
roles: Array.from(roles),
audioRoles: null,
videoId: null,
audioId: null,
channelsCount: null,
audioBandwidth: null,
videoBandwidth: null,
originalVideoId: null,
originalAudioId: null,
originalTextId: null,
};
if (video) {
track.videoId = video.id;
track.originalVideoId = video.originalId;
track.width = video.width || null;
track.height = video.height || null;
track.frameRate = video.frameRate || null;
track.videoBandwidth = video.bandwidth || null;
}
if (audio) {
track.audioId = audio.id;
track.originalAudioId = audio.originalId;
track.channelsCount = audio.channelsCount;
track.audioBandwidth = audio.bandwidth || null;
track.label = audio.label;
track.audioRoles = audio.roles;
}
return track;
};
/**
* @param {shaka.extern.Stream} stream
* @return {shaka.extern.Track}
*/
shaka.util.StreamUtils.textStreamToTrack = function(stream) {
const ContentType = shaka.util.ManifestParserUtils.ContentType;
/** @type {shaka.extern.Track} */
let track = {
id: stream.id,
active: false,
type: ContentType.TEXT,
bandwidth: 0,
language: stream.language,
label: stream.label,
kind: stream.kind || null,
width: null,
height: null,
frameRate: null,
mimeType: stream.mimeType,
codecs: stream.codecs || null,
audioCodec: null,
videoCodec: null,
primary: stream.primary,
roles: stream.roles,
audioRoles: null,
videoId: null,
audioId: null,
channelsCount: null,
audioBandwidth: null,
videoBandwidth: null,
originalVideoId: null,
originalAudioId: null,
originalTextId: stream.originalId,
};
return track;
};
/**
* Generate and return an ID for this track, since the ID field is optional.
*
* @param {TextTrack|AudioTrack} html5Track
* @return {number} The generated ID.
*/
shaka.util.StreamUtils.html5TrackId = function(html5Track) {
if (!html5Track['__shaka_id']) {
html5Track['__shaka_id'] = shaka.util.StreamUtils.nextTrackId_++;
}
return html5Track['__shaka_id'];
};
/** @private {number} */
shaka.util.StreamUtils.nextTrackId_ = 0;
/**
* @param {TextTrack} textTrack
* @return {shaka.extern.Track}
*/
shaka.util.StreamUtils.html5TextTrackToTrack = function(textTrack) {
const CLOSED_CAPTION_MIMETYPE = shaka.util.MimeUtils.CLOSED_CAPTION_MIMETYPE;
const StreamUtils = shaka.util.StreamUtils;
/** @type {shaka.extern.Track} */
const track = StreamUtils.html5TrackToGenericShakaTrack_(textTrack);
track.active = textTrack.mode != 'disabled';
track.type = 'text';
track.originalTextId = textTrack.id;
if (textTrack.kind == 'captions') {
track.mimeType = CLOSED_CAPTION_MIMETYPE;
}
return track;
};
/**
* @param {AudioTrack} audioTrack
* @return {shaka.extern.Track}
*/
shaka.util.StreamUtils.html5AudioTrackToTrack = function(audioTrack) {
const StreamUtils = shaka.util.StreamUtils;
/** @type {shaka.extern.Track} */
const track = StreamUtils.html5TrackToGenericShakaTrack_(audioTrack);
track.active = audioTrack.enabled;
track.type = 'variant';
track.originalAudioId = audioTrack.id;
if (audioTrack.kind == 'main') {
track.primary = true;
track.roles = ['main'];
track.audioRoles = ['main'];
} else {
track.audioRoles = [];
}
return track;
};
/**
* Creates a Track object with non-type specific fields filled out. The caller
* is responsible for completing the Track object with any type-specific
* information (audio or text).
*
* @param {TextTrack|AudioTrack} html5Track
* @return {shaka.extern.Track}
* @private
*/
shaka.util.StreamUtils.html5TrackToGenericShakaTrack_ = function(html5Track) {
/** @type {shaka.extern.Track} */
const track = {
id: shaka.util.StreamUtils.html5TrackId(html5Track),
active: false,
type: '',
bandwidth: 0,
language: shaka.util.LanguageUtils.normalize(html5Track.language),
label: html5Track.label,
kind: html5Track.kind,
width: null,
height: null,
frameRate: null,
mimeType: null,
codecs: null,
audioCodec: null,
videoCodec: null,
primary: false,
roles: [],
audioRoles: null,
videoId: null,
audioId: null,
channelsCount: null,
audioBandwidth: null,
videoBandwidth: null,
originalVideoId: null,
originalAudioId: null,
originalTextId: null,
};
return track;
};
/**
* Determines if the given variant is playable.
* @param {!shaka.extern.Variant} variant
* @return {boolean}
*/
shaka.util.StreamUtils.isPlayable = function(variant) {
return variant.allowedByApplication && variant.allowedByKeySystem;
};
/**
* Filters out unplayable variants.
* @param {!Array.<!shaka.extern.Variant>} variants
* @return {!Array.<!shaka.extern.Variant>}
*/
shaka.util.StreamUtils.getPlayableVariants = function(variants) {
return variants.filter(function(variant) {
return shaka.util.StreamUtils.isPlayable(variant);
});
};
/**
* Filters variants according to the given audio channel count config.
*
* @param {!Array.<shaka.extern.Variant>} variants
* @param {number} preferredAudioChannelCount
* @return {!Array.<!shaka.extern.Variant>}
*/
shaka.util.StreamUtils.filterVariantsByAudioChannelCount = function(
variants, preferredAudioChannelCount) {
// Group variants by their audio channel counts.
const variantsWithChannelCounts =
variants.filter((v) => v.audio && v.audio.channelsCount);
/** @type {!Map.<number, !Array.<shaka.extern.Variant>>} */
const variantsByChannelCount = new Map();
for (const variant of variantsWithChannelCounts) {
const count = variant.audio.channelsCount;
goog.asserts.assert(count != null, 'Must have count after filtering!');
if (!variantsByChannelCount.has(count)) {
variantsByChannelCount.set(count, []);
}
variantsByChannelCount.get(count).push(variant);
}
/** @type {!Array.<number>} */
const channelCounts = Array.from(variantsByChannelCount.keys());
// If no variant has audio channel count info, return the original variants.
if (channelCounts.length == 0) {
return variants;
}
// Choose the variants with the largest number of audio channels less than or
// equal to the configured number of audio channels.
const countLessThanOrEqualtoConfig =
channelCounts.filter((count) => count <= preferredAudioChannelCount);
if (countLessThanOrEqualtoConfig.length) {
return variantsByChannelCount.get(Math.max.apply(null,
countLessThanOrEqualtoConfig));
}
// If all variants have more audio channels than the config, choose the
// variants with the fewest audio channels.
return variantsByChannelCount.get(Math.min.apply(null, channelCounts));
};
/**
* Chooses streams according to the given config.
*
* @param {!Array.<shaka.extern.Stream>} streams
* @param {string} preferredLanguage
* @param {string} preferredRole
* @return {!Array.<!shaka.extern.Stream>}
*/
shaka.util.StreamUtils.filterStreamsByLanguageAndRole = function(
streams, preferredLanguage, preferredRole) {
const LanguageUtils = shaka.util.LanguageUtils;
/** @type {!Array.<!shaka.extern.Stream>} */
let chosen = streams;
// Start with the set of primary streams.
/** @type {!Array.<!shaka.extern.Stream>} */
let primary = streams.filter(function(stream) {
return stream.primary;
});
if (primary.length) {
chosen = primary;
}
// Now reduce the set to one language. This covers both arbitrary language
// choice and the reduction of the "primary" stream set to one language.
let firstLanguage = chosen.length ? chosen[0].language : '';
chosen = chosen.filter(function(stream) {
return stream.language == firstLanguage;
});
// Find the streams that best match our language preference. This will
// override previous selections.
if (preferredLanguage) {
const closestLocale = LanguageUtils.findClosestLocale(
LanguageUtils.normalize(preferredLanguage),
streams.map((stream) => stream.language));
// Only replace |chosen| if we found a locale that is close to our
// preference.
if (closestLocale) {
chosen = streams.filter((stream) => {
const locale = LanguageUtils.normalize(stream.language);
return locale == closestLocale;
});
}
}
// Now refine the choice based on role preference.
if (preferredRole) {
let roleMatches = shaka.util.StreamUtils.filterTextStreamsByRole_(
chosen, preferredRole);
if (roleMatches.length) {
return roleMatches;
} else {
shaka.log.warning('No exact match for the text role could be found.');
}
} else {
// Prefer text streams with no roles, if they exist.
let noRoleMatches = chosen.filter(function(stream) {
return stream.roles.length == 0;
});
if (noRoleMatches.length) {
return noRoleMatches;
}
}
// Either there was no role preference, or it could not be satisfied.
// Choose an arbitrary role, if there are any, and filter out any other roles.
// This ensures we never adapt between roles.
let allRoles = chosen.map(function(stream) {
return stream.roles;
}).reduce(shaka.util.Functional.collapseArrays, []);
if (!allRoles.length) {
return chosen;
}
return shaka.util.StreamUtils.filterTextStreamsByRole_(chosen, allRoles[0]);
};
/**
* Filter text Streams by role.
*
* @param {!Array.<shaka.extern.Stream>} textStreams
* @param {string} preferredRole
* @return {!Array.<shaka.extern.Stream>}
* @private
*/
shaka.util.StreamUtils.filterTextStreamsByRole_ =
function(textStreams, preferredRole) {
return textStreams.filter(function(stream) {
return stream.roles.includes(preferredRole);
});
};
/**
* Finds a Variant with given audio and video streams.
* Returns null if no such Variant was found.
*
* @param {?shaka.extern.Stream} audio
* @param {?shaka.extern.Stream} video
* @param {!Array.<!shaka.extern.Variant>} variants
* @return {?shaka.extern.Variant}
*/
shaka.util.StreamUtils.getVariantByStreams = function(audio, video, variants) {
if (audio) {
goog.asserts.assert(
shaka.util.StreamUtils.isAudio(audio),
'Audio streams must have the audio type.');
}
if (video) {
goog.asserts.assert(
shaka.util.StreamUtils.isVideo(video),
'Video streams must have the video type.');
}
for (let i = 0; i < variants.length; i++) {
if (variants[i].audio == audio && variants[i].video == video) {
return variants[i];
}
}
return null;
};
/**
* Checks if the given stream is an audio stream.
*
* @param {shaka.extern.Stream} stream
* @return {boolean}
*/
shaka.util.StreamUtils.isAudio = function(stream) {
const ContentType = shaka.util.ManifestParserUtils.ContentType;
return stream.type == ContentType.AUDIO;
};
/**
* Checks if the given stream is a video stream.
*
* @param {shaka.extern.Stream} stream
* @return {boolean}
*/
shaka.util.StreamUtils.isVideo = function(stream) {
const ContentType = shaka.util.ManifestParserUtils.ContentType;
return stream.type == ContentType.VIDEO;
};
/**
* Get all non-null streams in the variant as an array.
*
* @param {shaka.extern.Variant} variant
* @return {!Array.<shaka.extern.Stream>}
*/
shaka.util.StreamUtils.getVariantStreams = function(variant) {
const streams = [];
if (variant.audio) { streams.push(variant.audio); }
if (variant.video) { streams.push(variant.video); }
return streams;
};
/**
* @param {shaka.extern.Stream} stream
* @return {string}
* @private
*/
shaka.util.StreamUtils.getStreamSummaryString_ = function(stream) {
if (shaka.util.StreamUtils.isAudio(stream)) {
return 'type=audio' +
' codecs=' + stream.codecs +
' bandwidth='+ stream.bandwidth +
' channelsCount=' + stream.channelsCount;
}
if (shaka.util.StreamUtils.isVideo(stream)) {
return 'type=video' +
' codecs=' + stream.codecs +
' bandwidth=' + stream.bandwidth +
' frameRate=' + stream.frameRate +
' width=' + stream.width +
' height=' + stream.height;
}
return 'unexpected stream type';
};