shaka-player
Version:
DASH/EME video player library
314 lines (275 loc) • 9.23 kB
JavaScript
/**
* @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.offline.ManifestConverter');
goog.require('goog.asserts');
goog.require('shaka.media.InitSegmentReference');
goog.require('shaka.media.PresentationTimeline');
goog.require('shaka.media.SegmentIndex');
goog.require('shaka.media.SegmentReference');
goog.require('shaka.offline.OfflineUri');
goog.require('shaka.util.ManifestParserUtils');
/**
* Utility class for converting database manifest objects back to normal
* player-ready objects. Used by the offline system to convert on-disk
* objects back to the in-memory objects.
*/
shaka.offline.ManifestConverter = class {
/**
* Create a new manifest converter. Need to know the mechanism and cell that
* the manifest is from so that all segments paths can be created.
*
* @param {string} mechanism
* @param {string} cell
*/
constructor(mechanism, cell) {
/** @private {string} */
this.mechanism_ = mechanism;
/** @private {string} */
this.cell_ = cell;
}
/**
* Convert a |shaka.extern.ManifestDB| object to a |shaka.extern.Manifest|
* object.
*
* @param {shaka.extern.ManifestDB} manifestDB
* @return {shaka.extern.Manifest}
*/
fromManifestDB(manifestDB) {
let timeline = new shaka.media.PresentationTimeline(null, 0);
timeline.setDuration(manifestDB.duration);
let periods = manifestDB.periods.map((period) =>
this.fromPeriodDB(period, timeline));
let drmInfos = manifestDB.drmInfo ? [manifestDB.drmInfo] : [];
if (manifestDB.drmInfo) {
periods.forEach((period) => {
period.variants.forEach((variant) => { variant.drmInfos = drmInfos; });
});
}
return {
presentationTimeline: timeline,
minBufferTime: 2,
offlineSessionIds: manifestDB.sessionIds,
periods: periods,
};
}
/**
* Create a period object from a database period.
*
* @param {shaka.extern.PeriodDB} period
* @param {shaka.media.PresentationTimeline} timeline
* @return {shaka.extern.Period}
*/
fromPeriodDB(period, timeline) {
/** @type {!Array.<shaka.extern.StreamDB>} */
let audioStreams = period.streams.filter((stream) => this.isAudio_(stream));
/** @type {!Array.<shaka.extern.StreamDB>} */
let videoStreams = period.streams.filter((stream) => this.isVideo_(stream));
/** @type {!Map.<number, shaka.extern.Variant>} */
const variants = this.createVariants(audioStreams, videoStreams);
/** @type {!Array.<shaka.extern.Stream>} */
let textStreams = period.streams
.filter((stream) => this.isText_(stream))
.map((stream) => this.fromStreamDB_(stream));
period.streams.forEach((stream, i) => {
/** @type {!Array.<!shaka.media.SegmentReference>} */
let refs = stream.segments.map((segment, index) => {
return this.fromSegmentDB_(index, segment);
});
timeline.notifySegments(refs, period.startTime);
});
return {
startTime: period.startTime,
variants: Array.from(variants.values()),
textStreams: textStreams,
};
}
/**
* Recreates Variants from audio and video StreamDB collections.
*
* @param {!Array.<!shaka.extern.StreamDB>} audios
* @param {!Array.<!shaka.extern.StreamDB>} videos
* @return {!Map.<number, !shaka.extern.Variant>}
*/
createVariants(audios, videos) {
// Get all the variant ids from all audio and video streams.
/** @type {!Set.<number>} */
const variantIds = new Set();
for (const stream of audios) {
for (const id of stream.variantIds) { variantIds.add(id); }
}
for (const stream of videos) {
for (const id of stream.variantIds) { variantIds.add(id); }
}
/** @type {!Map.<number, shaka.extern.Variant>} */
const variantMap = new Map();
for (const id of variantIds) {
variantMap.set(id, this.createEmptyVariant_(id));
}
// Assign each audio stream to its variants.
for (const audio of audios) {
/** @type {shaka.extern.Stream} */
const stream = this.fromStreamDB_(audio);
for (const variantId of audio.variantIds) {
const variant = variantMap.get(variantId);
goog.asserts.assert(
!variant.audio, 'A variant should only have one audio stream');
variant.language = stream.language;
variant.primary = variant.primary || stream.primary;
variant.audio = stream;
}
}
// Assign each video stream to its variants.
for (const video of videos) {
/** @type {shaka.extern.Stream} */
const stream = this.fromStreamDB_(video);
for (const variantId of video.variantIds) {
const variant = variantMap.get(variantId);
goog.asserts.assert(
!variant.video, 'A variant should only have one video stream');
variant.primary = variant.primary || stream.primary;
variant.video = stream;
}
}
return variantMap;
}
/**
* @param {shaka.extern.StreamDB} streamDB
* @return {shaka.extern.Stream}
* @private
*/
fromStreamDB_(streamDB) {
/** @type {!Array.<!shaka.media.SegmentReference>} */
let segments = streamDB.segments.map((segment, index) =>
this.fromSegmentDB_(index, segment));
/** @type {!shaka.media.SegmentIndex} */
let segmentIndex = new shaka.media.SegmentIndex(segments);
/** @type {shaka.extern.Stream} */
let stream = {
id: streamDB.id,
originalId: streamDB.originalId,
createSegmentIndex: () => Promise.resolve(),
findSegmentPosition: (index) => segmentIndex.find(index),
getSegmentReference: (index) => segmentIndex.get(index),
initSegmentReference: null,
presentationTimeOffset: streamDB.presentationTimeOffset,
mimeType: streamDB.mimeType,
codecs: streamDB.codecs,
width: streamDB.width || undefined,
height: streamDB.height || undefined,
frameRate: streamDB.frameRate || undefined,
pixelAspectRatio: streamDB.pixelAspectRatio || undefined,
kind: streamDB.kind,
encrypted: streamDB.encrypted,
keyId: streamDB.keyId,
language: streamDB.language,
label: streamDB.label || null,
type: streamDB.contentType,
primary: streamDB.primary,
trickModeVideo: null,
// TODO(modmaker): Store offline?
emsgSchemeIdUris: null,
roles: [],
channelsCount: null,
audioSamplingRate: null,
closedCaptions: null,
};
if (streamDB.initSegmentKey != null) {
stream.initSegmentReference =
this.fromInitSegmentDB_(streamDB.initSegmentKey);
}
return stream;
}
/**
* @param {number} index
* @param {shaka.extern.SegmentDB} segmentDB
* @return {!shaka.media.SegmentReference}
* @private
*/
fromSegmentDB_(index, segmentDB) {
/** @type {!shaka.offline.OfflineUri} */
let uri = shaka.offline.OfflineUri.segment(
this.mechanism_, this.cell_, segmentDB.dataKey);
return new shaka.media.SegmentReference(
index,
segmentDB.startTime,
segmentDB.endTime,
() => [uri.toString()],
0 /* startByte */,
null /* endByte */);
}
/**
* @param {number} key
* @return {!shaka.media.InitSegmentReference}
* @private
*/
fromInitSegmentDB_(key) {
/** @type {!shaka.offline.OfflineUri} */
let uri = shaka.offline.OfflineUri.segment(
this.mechanism_, this.cell_, key);
return new shaka.media.InitSegmentReference(
() => [uri.toString()],
0 /* startBytes*/,
null /* endBytes */);
}
/**
* @param {shaka.extern.StreamDB} stream
* @return {boolean}
* @private
*/
isAudio_(stream) {
const ContentType = shaka.util.ManifestParserUtils.ContentType;
return stream.contentType == ContentType.AUDIO;
}
/**
* @param {shaka.extern.StreamDB} stream
* @return {boolean}
* @private
*/
isVideo_(stream) {
const ContentType = shaka.util.ManifestParserUtils.ContentType;
return stream.contentType == ContentType.VIDEO;
}
/**
* @param {shaka.extern.StreamDB} stream
* @return {boolean}
* @private
*/
isText_(stream) {
const ContentType = shaka.util.ManifestParserUtils.ContentType;
return stream.contentType == ContentType.TEXT;
}
/**
* Creates an empty Variant.
*
* @param {number} id
* @return {!shaka.extern.Variant}
* @private
*/
createEmptyVariant_(id) {
return {
id: id,
language: '',
primary: false,
audio: null,
video: null,
bandwidth: 0,
drmInfos: [],
allowedByApplication: true,
allowedByKeySystem: true,
};
}
};