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fix: Linear DASH multiperiod label issue (#1352)
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* fix: Linear DASH multiperiod label issue

* fix current tests

* remove old mediaGroup labels

* comments

* unit test

* comments

* fix unused parameter name

* syntax fix
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@adrums86
adrums86 committed Dec 20, 2022
1 parent afb1ff7 commit d7e8713
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Showing 3 changed files with 186 additions and 13 deletions.
41 changes: 40 additions & 1 deletion src/dash-playlist-loader.js
View file
Original file line number Diff line number Diff line change
Expand Up @@ -86,6 +86,19 @@ const dashPlaylistUnchanged = function(a, b) {
return true;
};

/**
* Use the representation IDs from the mpd object to create groupIDs, the NAME is set to mandatory representation
* ID in the parser. This allows for continuous playout across periods with the same representation IDs
* (continuous periods as defined in DASH-IF 3.2.12). This is assumed in the mpd-parser as well. If we want to support
* periods without continuous playback this function may need modification as well as the parser.
*/
const dashGroupId = (type, group, label, playlist) => {
// If the manifest somehow does not have an ID (non-dash compliant), use the label.
const playlistId = playlist.attributes.NAME || label;

return `placeholder-uri-${type}-${group}-${playlistId}`;
};

/**
* Parses the main XML string and updates playlist URI references.
*
Expand Down Expand Up @@ -116,11 +129,27 @@ export const parseMainXml = ({
previousManifest
});

addPropertiesToMain(manifest, srcUrl);
addPropertiesToMain(manifest, srcUrl, dashGroupId);

return manifest;
};

/**
* Removes any mediaGroup labels that no longer exist in the newMain
*
* @param {Object} update
* The previous mpd object being updated
* @param {Object} newMain
* The new mpd object
*/
const removeOldMediaGroupLabels = (update, newMain) => {
forEachMediaGroup(update, (properties, type, group, label) => {
if (!(label in newMain.mediaGroups[type][group])) {
delete update.mediaGroups[type][group][label];
}
});
};

/**
* Returns a new main manifest that is the result of merging an updated main manifest
* into the original version.
Expand Down Expand Up @@ -170,13 +199,23 @@ export const updateMain = (oldMain, newMain, sidxMapping) => {

if (playlistUpdate) {
update = playlistUpdate;

// add new mediaGroup label if it doesn't exist and assign the new mediaGroup.
if (!(label in update.mediaGroups[type][group])) {
update.mediaGroups[type][group][label] = properties;
}

// update the playlist reference within media groups
update.mediaGroups[type][group][label].playlists[0] = update.playlists[id];

noChanges = false;
}
}
});

// remove mediaGroup labels and references that no longer exist in the newMain
removeOldMediaGroupLabels(update, newMain);

if (newMain.minimumUpdatePeriod !== oldMain.minimumUpdatePeriod) {
noChanges = false;
}
Expand Down
12 changes: 9 additions & 3 deletions src/manifest.js
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Original file line number Diff line number Diff line change
Expand Up @@ -10,6 +10,11 @@ export const createPlaylistID = (index, uri) => {
return `${index}-${uri}`;
};

// default function for creating a group id
const groupID = (type, group, label) => {
return `placeholder-uri-${type}-${group}-${label}`;
};

/**
* Parses a given m3u8 playlist
*
Expand Down Expand Up @@ -265,8 +270,10 @@ export const mainForMedia = (media, uri) => {
* main manifest object
* @param {string} uri
* The source URI
* @param {function} createGroupID
* A function to determine how to create the groupID for mediaGroups
*/
export const addPropertiesToMain = (main, uri) => {
export const addPropertiesToMain = (main, uri, createGroupID = groupID) => {
main.uri = uri;

for (let i = 0; i < main.playlists.length; i++) {
Expand All @@ -282,8 +289,6 @@ export const addPropertiesToMain = (main, uri) => {
const audioOnlyMain = isAudioOnly(main);

forEachMediaGroup(main, (properties, mediaType, groupKey, labelKey) => {
const groupId = `placeholder-uri-${mediaType}-${groupKey}-${labelKey}`;

// add a playlist array under properties
if (!properties.playlists || !properties.playlists.length) {
// If the manifest is audio only and this media group does not have a uri, check
Expand All @@ -303,6 +308,7 @@ export const addPropertiesToMain = (main, uri) => {
}

properties.playlists.forEach(function(p, i) {
const groupId = createGroupID(mediaType, groupKey, labelKey, p);
const id = createPlaylistID(i, groupId);

if (p.uri) {
Expand Down
146 changes: 137 additions & 9 deletions test/dash-playlist-loader.test.js
View file
Original file line number Diff line number Diff line change
Expand Up @@ -557,7 +557,7 @@ QUnit.test('filterChangedSidxMappings: removes change sidx info from mapping', f
);
const playlists = loader.main.playlists;
const oldVideoKey = generateSidxKey(playlists['0-placeholder-uri-0'].sidx);
const oldAudioEnKey = generateSidxKey(playlists['0-placeholder-uri-AUDIO-audio-en'].sidx);
const oldAudioEnKey = generateSidxKey(playlists['0-placeholder-uri-AUDIO-audio-audio'].sidx);

let mainXml = loader.mainXml_.replace(/(indexRange)=\"\d+-\d+\"/, '$1="201-400"');
// should change the video playlist
Expand Down Expand Up @@ -1394,7 +1394,7 @@ QUnit.test('haveMain: sets media on child loader', function(assert) {

loader.load();
this.standardXHRResponse(this.requests.shift());
const childPlaylist = loader.main.playlists['0-placeholder-uri-AUDIO-audio-main'];
const childPlaylist = loader.main.playlists['0-placeholder-uri-AUDIO-audio-audio'];
const childLoader = new DashPlaylistLoader(childPlaylist, this.fakeVhs, false, loader);

const mediaStub = sinon.stub(childLoader, 'media');
Expand Down Expand Up @@ -2031,7 +2031,7 @@ QUnit.test('hasPendingRequest: returns true if async code is running in child lo

loader.load();
this.standardXHRResponse(this.requests.shift());
const childPlaylist = loader.main.playlists['0-placeholder-uri-AUDIO-audio-main'];
const childPlaylist = loader.main.playlists['0-placeholder-uri-AUDIO-audio-audio'];
const childLoader = new DashPlaylistLoader(childPlaylist, this.fakeVhs, false, loader);

assert.notOk(childLoader.hasPendingRequest(), 'no pending requests on construction');
Expand Down Expand Up @@ -2192,7 +2192,7 @@ QUnit.test('child loader moves to HAVE_METADATA when initialized with a main pla

loader.load();
this.standardXHRResponse(this.requests.shift());
const playlist = loader.main.playlists['0-placeholder-uri-AUDIO-audio-main'];
const playlist = loader.main.playlists['0-placeholder-uri-AUDIO-audio-audio'];
const childLoader = new DashPlaylistLoader(playlist, this.fakeVhs, false, loader);

childLoader.on('loadedplaylist', function() {
Expand Down Expand Up @@ -2225,7 +2225,7 @@ QUnit.test('child playlist moves to HAVE_METADATA when initialized with a live m

loader.load();
this.standardXHRResponse(this.requests.shift());
const playlist = loader.main.playlists['0-placeholder-uri-AUDIO-audio-main'];
const playlist = loader.main.playlists['0-placeholder-uri-AUDIO-audio-audio'];
const childLoader = new DashPlaylistLoader(playlist, this.fakeVhs, false, loader);

childLoader.on('loadedplaylist', function() {
Expand Down Expand Up @@ -2463,14 +2463,14 @@ QUnit.test(
);
assert.equal(
loader.main.mediaGroups.AUDIO.audio.main.playlists[0].uri,
'placeholder-uri-AUDIO-audio-main', 'setup phony uri for media groups'
'placeholder-uri-AUDIO-audio-audio', 'setup phony uri for media groups'
);
assert.equal(
loader.main.mediaGroups.AUDIO.audio.main.playlists[0].id,
'0-placeholder-uri-AUDIO-audio-main', 'setup phony id for media groups'
'0-placeholder-uri-AUDIO-audio-audio', 'setup phony id for media groups'
);
assert.strictEqual(
loader.main.playlists['0-placeholder-uri-AUDIO-audio-main'],
loader.main.playlists['0-placeholder-uri-AUDIO-audio-audio'],
loader.main.mediaGroups.AUDIO.audio.main.playlists[0],
'set reference by uri for easy access'
);
Expand Down Expand Up @@ -2699,7 +2699,7 @@ QUnit.test('child loaders wait for async action before moving to HAVE_MAIN_MANIF

loader.load();
this.standardXHRResponse(this.requests.shift());
const childPlaylist = loader.main.playlists['0-placeholder-uri-AUDIO-audio-main'];
const childPlaylist = loader.main.playlists['0-placeholder-uri-AUDIO-audio-audio'];
const childLoader = new DashPlaylistLoader(childPlaylist, this.fakeVhs, false, loader);

childLoader.load();
Expand Down Expand Up @@ -2860,3 +2860,131 @@ QUnit.test('updateMain: merges in top level timelineStarts', function(assert) {

assert.deepEqual(update.timelineStarts, [2], 'updated timelineStarts');
});

QUnit.test('updateMain: updates playlists and mediaGroups when labels change', function(assert) {
const main = {
duration: 10,
minimumUpdatePeriod: 0,
timelineStarts: [],
mediaGroups: {
AUDIO: {
audio: {
main: {
playlists: [{
mediaSequence: 0,
attributes: {},
id: 'audio-0-uri',
uri: 'audio-0-uri',
resolvedUri: urlTo('audio-0-uri'),
segments: [{
duration: 10,
uri: 'audio-segment-0-uri',
resolvedUri: urlTo('audio-segment-0-uri')
}]
}]
}
}
}
},
playlists: [{
mediaSequence: 0,
attributes: {
BANDWIDTH: 9
},
id: 'playlist-0-uri',
uri: 'playlist-0-uri',
resolvedUri: urlTo('playlist-0-uri'),
segments: [{
duration: 10,
uri: 'segment-0-uri',
resolvedUri: urlTo('segment-0-uri')
}]
}]
};
const update = {
duration: 20,
minimumUpdatePeriod: 0,
timelineStarts: [],
mediaGroups: {
AUDIO: {
audio: {
update: {
playlists: [{
mediaSequence: 1,
attributes: {},
id: 'audio-0-uri',
uri: 'audio-0-uri',
resolvedUri: urlTo('audio-0-uri'),
segments: [{
duration: 10,
uri: 'audio-segment-0-uri',
resolvedUri: urlTo('audio-segment-0-uri')
}]
}]
}
}
}
},
playlists: [{
mediaSequence: 1,
attributes: {
BANDWIDTH: 9
},
id: 'playlist-0-uri',
uri: 'playlist-0-uri',
resolvedUri: urlTo('playlist-0-uri'),
segments: [{
duration: 10,
uri: 'segment-0-uri',
resolvedUri: urlTo('segment-0-uri')
}]
}]
};

main.playlists['playlist-0-uri'] = main.playlists[0];
main.playlists['audio-0-uri'] = main.mediaGroups.AUDIO.audio.main.playlists[0];

assert.deepEqual(
updateMain(main, update),
{
duration: 20,
minimumUpdatePeriod: 0,
timelineStarts: [],
mediaGroups: {
AUDIO: {
audio: {
update: {
playlists: [{
mediaSequence: 1,
attributes: {},
id: 'audio-0-uri',
uri: 'audio-0-uri',
resolvedUri: urlTo('audio-0-uri'),
segments: [{
duration: 10,
uri: 'audio-segment-0-uri',
resolvedUri: urlTo('audio-segment-0-uri')
}]
}]
}
}
}
},
playlists: [{
mediaSequence: 1,
attributes: {
BANDWIDTH: 9
},
id: 'playlist-0-uri',
uri: 'playlist-0-uri',
resolvedUri: urlTo('playlist-0-uri'),
segments: [{
duration: 10,
uri: 'segment-0-uri',
resolvedUri: urlTo('segment-0-uri')
}]
}]
},
'updates playlists and media groups'
);
});

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