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stream-controller.js
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stream-controller.js
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/*
* Stream Controller
*/
import BinarySearch from '../utils/binary-search';
import BufferHelper from '../helper/buffer-helper';
import Demuxer from '../demux/demuxer';
import Event from '../events';
import EventHandler from '../event-handler';
import LevelHelper from '../helper/level-helper';
import TimeRanges from '../utils/timeRanges';
import {ErrorTypes, ErrorDetails} from '../errors';
import {logger} from '../utils/logger';
const State = {
STOPPED : 'STOPPED',
IDLE : 'IDLE',
KEY_LOADING : 'KEY_LOADING',
FRAG_LOADING : 'FRAG_LOADING',
FRAG_LOADING_WAITING_RETRY : 'FRAG_LOADING_WAITING_RETRY',
WAITING_LEVEL : 'WAITING_LEVEL',
PARSING : 'PARSING',
PARSED : 'PARSED',
BUFFER_FLUSHING : 'BUFFER_FLUSHING',
ENDED : 'ENDED',
ERROR : 'ERROR'
};
class StreamController extends EventHandler {
constructor(hls) {
super(hls,
Event.MEDIA_ATTACHED,
Event.MEDIA_DETACHING,
Event.MANIFEST_LOADING,
Event.MANIFEST_PARSED,
Event.LEVEL_LOADED,
Event.KEY_LOADED,
Event.FRAG_LOADED,
Event.FRAG_LOAD_EMERGENCY_ABORTED,
Event.FRAG_PARSING_INIT_SEGMENT,
Event.FRAG_PARSING_DATA,
Event.FRAG_PARSED,
Event.ERROR,
Event.AUDIO_TRACK_SWITCH,
Event.BUFFER_CREATED,
Event.BUFFER_APPENDED,
Event.BUFFER_FLUSHED);
this.config = hls.config;
this.audioCodecSwap = false;
this.ticks = 0;
this.ontick = this.tick.bind(this);
}
destroy() {
this.stopLoad();
if (this.timer) {
clearInterval(this.timer);
this.timer = null;
}
EventHandler.prototype.destroy.call(this);
this.state = State.STOPPED;
}
startLoad(startPosition) {
if (this.levels) {
let lastCurrentTime = this.lastCurrentTime, hls = this.hls;
this.stopLoad();
if (!this.timer) {
this.timer = setInterval(this.ontick, 100);
}
this.level = -1;
this.fragLoadError = 0;
if (!this.startFragRequested) {
// determine load level
let startLevel = hls.startLevel;
if (startLevel === -1) {
// -1 : guess start Level by doing a bitrate test by loading first fragment of lowest quality level
startLevel = 0;
this.bitrateTest = true;
}
// set new level to playlist loader : this will trigger start level load
// hls.nextLoadLevel remains until it is set to a new value or until a new frag is successfully loaded
this.level = hls.nextLoadLevel = startLevel;
this.loadedmetadata = false;
}
// if startPosition undefined but lastCurrentTime set, set startPosition to last currentTime
if (lastCurrentTime > 0 && startPosition === -1) {
logger.log(`override startPosition with lastCurrentTime @${lastCurrentTime.toFixed(3)}`);
startPosition = lastCurrentTime;
}
this.state = State.IDLE;
this.nextLoadPosition = this.startPosition = this.lastCurrentTime = startPosition;
this.tick();
} else {
logger.warn('cannot start loading as manifest not parsed yet');
this.state = State.STOPPED;
}
}
stopLoad() {
var frag = this.fragCurrent;
if (frag) {
if (frag.loader) {
frag.loader.abort();
}
this.fragCurrent = null;
}
this.fragPrevious = null;
if (this.demuxer) {
this.demuxer.destroy();
this.demuxer = null;
}
this.state = State.STOPPED;
}
tick() {
this.ticks++;
if (this.ticks === 1) {
this.doTick();
if (this.ticks > 1) {
setTimeout(this.tick, 1);
}
this.ticks = 0;
}
}
doTick() {
switch(this.state) {
case State.ERROR:
//don't do anything in error state to avoid breaking further ...
break;
case State.BUFFER_FLUSHING:
// in buffer flushing state, reset fragLoadError counter
this.fragLoadError = 0;
break;
case State.IDLE:
// when this returns false there was an error and we shall return immediatly
// from current tick
if (!this._doTickIdle()) {
return;
}
break;
case State.WAITING_LEVEL:
var level = this.levels[this.level];
// check if playlist is already loaded
if (level && level.details) {
this.state = State.IDLE;
}
break;
case State.FRAG_LOADING_WAITING_RETRY:
var now = performance.now();
var retryDate = this.retryDate;
// if current time is gt than retryDate, or if media seeking let's switch to IDLE state to retry loading
if(!retryDate || (now >= retryDate) || (this.media && this.media.seeking)) {
logger.log(`mediaController: retryDate reached, switch back to IDLE state`);
this.state = State.IDLE;
}
break;
case State.ERROR:
case State.PAUSED:
case State.STOPPED:
case State.FRAG_LOADING:
case State.PARSING:
case State.PARSED:
case State.ENDED:
break;
default:
break;
}
// check buffer
this._checkBuffer();
// check/update current fragment
this._checkFragmentChanged();
}
// Ironically the "idle" state is the on we do the most logic in it seems ....
// NOTE: Maybe we could rather schedule a check for buffer length after half of the currently
// played segment, or on pause/play/seek instead of naively checking every 100ms?
_doTickIdle() {
const hls = this.hls,
config = hls.config,
media = this.media;
// if video not attached AND
// start fragment already requested OR start frag prefetch disable
// exit loop
// => if start level loaded and media not attached but start frag prefetch is enabled and start frag not requested yet, we will not exit loop
if (this.levelLastLoaded !== undefined && !media &&
(this.startFragRequested || !config.startFragPrefetch)) {
return true;
}
// if we have not yet loaded any fragment, start loading from start position
let pos;
if (this.loadedmetadata) {
pos = media.currentTime;
} else {
pos = this.nextLoadPosition;
}
// determine next load level
let level = hls.nextLoadLevel,
levelInfo = this.levels[level],
levelBitrate = levelInfo.bitrate,
maxBufLen;
// compute max Buffer Length that we could get from this load level, based on level bitrate. don't buffer more than 60 MB and more than 30s
if (levelBitrate) {
maxBufLen = Math.max(8 * config.maxBufferSize / levelBitrate, config.maxBufferLength);
} else {
maxBufLen = config.maxBufferLength;
}
maxBufLen = Math.min(maxBufLen, config.maxMaxBufferLength);
// determine next candidate fragment to be loaded, based on current position and end of buffer position
// ensure up to `config.maxMaxBufferLength` of buffer upfront
const bufferInfo = BufferHelper.bufferInfo(this.mediaBuffer ? this.mediaBuffer : media, pos, config.maxBufferHole),
bufferLen = bufferInfo.len;
// Stay idle if we are still with buffer margins
if (bufferLen >= maxBufLen) {
return true;
}
// if buffer length is less than maxBufLen try to load a new fragment ...
logger.trace(`buffer length of ${bufferLen.toFixed(3)} is below max of ${maxBufLen.toFixed(3)}. checking for more payload ...`);
// set next load level : this will trigger a playlist load if needed
this.level = hls.nextLoadLevel = level;
const levelDetails = levelInfo.details;
// if level info not retrieved yet, switch state and wait for level retrieval
// if live playlist, ensure that new playlist has been refreshed to avoid loading/try to load
// a useless and outdated fragment (that might even introduce load error if it is already out of the live playlist)
if (typeof levelDetails === 'undefined' || levelDetails.live && this.levelLastLoaded !== level) {
this.state = State.WAITING_LEVEL;
return true;
}
// we just got done loading the final fragment, check if we need to finalize media stream
let fragPrevious = this.fragPrevious;
if (!levelDetails.live && fragPrevious && fragPrevious.sn === levelDetails.endSN) {
// if (we are not seeking AND current position is buffered) OR (if we are seeking but everything (almost) til the end is buffered), let's signal eos
// we don't compare exactly media.duration === bufferInfo.end as there could be some subtle media duration difference when switching
// between different renditions. using half frag duration should help cope with these cases.
if ((!media.seeking && bufferInfo.len) || (media.duration-bufferInfo.end) <= fragPrevious.duration/2) {
// Finalize the media stream
let data = {};
if (this.altAudio) {
data.type = 'video';
}
this.hls.trigger(Event.BUFFER_EOS,data);
this.state = State.ENDED;
return true;
}
}
// if we have the levelDetails for the selected variant, lets continue enrichen our stream (load keys/fragments or trigger EOS, etc..)
return this._fetchPayloadOrEos({pos, bufferInfo, levelDetails});
}
_fetchPayloadOrEos({pos, bufferInfo, levelDetails}) {
const fragPrevious = this.fragPrevious,
level = this.level,
fragments = levelDetails.fragments,
fragLen = fragments.length;
// empty playlist
if (fragLen === 0) {
return false;
}
// find fragment index, contiguous with end of buffer position
let start = fragments[0].start,
end = fragments[fragLen-1].start + fragments[fragLen-1].duration,
bufferEnd = bufferInfo.end,
frag;
// in case of live playlist we need to ensure that requested position is not located before playlist start
if (levelDetails.live) {
let initialLiveManifestSize = this.config.initialLiveManifestSize;
if(fragLen < initialLiveManifestSize){
logger.warn(`Can not start playback of a level, reason: not enough fragments ${fragLen} < ${initialLiveManifestSize}`);
return false;
}
frag = this._ensureFragmentAtLivePoint({levelDetails, bufferEnd, start, end, fragPrevious, fragments, fragLen});
// if it explicitely returns null don't load any fragment and exit function now
if (frag === null) {
return false;
}
} else {
// VoD playlist: if bufferEnd before start of playlist, load first fragment
if (bufferEnd < start) {
frag = fragments[0];
}
}
if (!frag) {
frag = this._findFragment({start, fragPrevious, fragLen, fragments, bufferEnd, end, levelDetails});
}
if(frag) {
return this._loadFragmentOrKey({frag, level, levelDetails, pos, bufferEnd});
}
return true;
}
_ensureFragmentAtLivePoint({levelDetails, bufferEnd, start, end, fragPrevious, fragments, fragLen}) {
const config = this.hls.config, media = this.media;
let frag;
// check if requested position is within seekable boundaries :
//logger.log(`start/pos/bufEnd/seeking:${start.toFixed(3)}/${pos.toFixed(3)}/${bufferEnd.toFixed(3)}/${this.media.seeking}`);
let maxLatency = config.liveMaxLatencyDuration !== undefined ? config.liveMaxLatencyDuration : config.liveMaxLatencyDurationCount*levelDetails.targetduration;
if (bufferEnd < Math.max(start, end - maxLatency)) {
let liveSyncPosition = this.liveSyncPosition = this.computeLivePosition(start, levelDetails);
logger.log(`buffer end: ${bufferEnd.toFixed(3)} is located too far from the end of live sliding playlist, reset currentTime to : ${liveSyncPosition.toFixed(3)}`);
bufferEnd = liveSyncPosition;
if (media && media.readyState && media.duration > liveSyncPosition) {
media.currentTime = liveSyncPosition;
}
}
// if end of buffer greater than live edge, don't load any fragment
// this could happen if live playlist intermittently slides in the past.
// level 1 loaded [182580161,182580167]
// level 1 loaded [182580162,182580169]
// Loading 182580168 of [182580162 ,182580169],level 1 ..
// Loading 182580169 of [182580162 ,182580169],level 1 ..
// level 1 loaded [182580162,182580168] <============= here we should have bufferEnd > end. in that case break to avoid reloading 182580168
// level 1 loaded [182580164,182580171]
//
// don't return null in case media not loaded yet (readystate === 0)
if (levelDetails.PTSKnown && bufferEnd > end && media && media.readyState) {
return null;
}
if (this.startFragRequested && !levelDetails.PTSKnown) {
/* we are switching level on live playlist, but we don't have any PTS info for that quality level ...
try to load frag matching with next SN.
even if SN are not synchronized between playlists, loading this frag will help us
compute playlist sliding and find the right one after in case it was not the right consecutive one */
if (fragPrevious) {
var targetSN = fragPrevious.sn + 1;
if (targetSN >= levelDetails.startSN && targetSN <= levelDetails.endSN) {
frag = fragments[targetSN - levelDetails.startSN];
logger.log(`live playlist, switching playlist, load frag with next SN: ${frag.sn}`);
}
}
if (!frag) {
/* we have no idea about which fragment should be loaded.
so let's load mid fragment. it will help computing playlist sliding and find the right one
*/
frag = fragments[Math.min(fragLen - 1, Math.round(fragLen / 2))];
logger.log(`live playlist, switching playlist, unknown, load middle frag : ${frag.sn}`);
}
}
return frag;
}
_findFragment({start, fragPrevious, fragLen, fragments, bufferEnd, end, levelDetails}) {
const config = this.hls.config;
let frag,
foundFrag,
maxFragLookUpTolerance = config.maxFragLookUpTolerance;
if (bufferEnd < end) {
if (bufferEnd > end - maxFragLookUpTolerance) {
maxFragLookUpTolerance = 0;
}
foundFrag = BinarySearch.search(fragments, (candidate) => {
// offset should be within fragment boundary - config.maxFragLookUpTolerance
// this is to cope with situations like
// bufferEnd = 9.991
// frag[Ø] : [0,10]
// frag[1] : [10,20]
// bufferEnd is within frag[0] range ... although what we are expecting is to return frag[1] here
// frag start frag start+duration
// |-----------------------------|
// <---> <--->
// ...--------><-----------------------------><---------....
// previous frag matching fragment next frag
// return -1 return 0 return 1
//logger.log(`level/sn/start/end/bufEnd:${level}/${candidate.sn}/${candidate.start}/${(candidate.start+candidate.duration)}/${bufferEnd}`);
if ((candidate.start + candidate.duration - maxFragLookUpTolerance) <= bufferEnd) {
return 1;
}// if maxFragLookUpTolerance will have negative value then don't return -1 for first element
else if (candidate.start - maxFragLookUpTolerance > bufferEnd && candidate.start) {
return -1;
}
return 0;
});
} else {
// reach end of playlist
foundFrag = fragments[fragLen-1];
}
if (foundFrag) {
frag = foundFrag;
start = foundFrag.start;
//logger.log('find SN matching with pos:' + bufferEnd + ':' + frag.sn);
if (fragPrevious && frag.level === fragPrevious.level && frag.sn === fragPrevious.sn) {
if (frag.sn < levelDetails.endSN) {
let deltaPTS = fragPrevious.deltaPTS,
curSNIdx = frag.sn - levelDetails.startSN;
// if there is a significant delta between audio and video, larger than max allowed hole,
// and if previous remuxed fragment did not start with a keyframe. (fragPrevious.dropped)
// let's try to load previous fragment again to get last keyframe
// then we will reload again current fragment (that way we should be able to fill the buffer hole ...)
if (deltaPTS && deltaPTS > config.maxBufferHole && fragPrevious.dropped && curSNIdx) {
frag = fragments[curSNIdx-1];
logger.warn(`SN just loaded, with large PTS gap between audio and video, maybe frag is not starting with a keyframe ? load previous one to try to overcome this`);
// decrement previous frag load counter to avoid frag loop loading error when next fragment will get reloaded
fragPrevious.loadCounter--;
} else {
frag = fragments[curSNIdx+1];
logger.log(`SN just loaded, load next one: ${frag.sn}`);
}
} else {
frag = null;
}
}
}
return frag;
}
_loadFragmentOrKey({frag, level, levelDetails, pos, bufferEnd}) {
const hls = this.hls,
config = hls.config;
//logger.log('loading frag ' + i +',pos/bufEnd:' + pos.toFixed(3) + '/' + bufferEnd.toFixed(3));
if ((frag.decryptdata.uri != null) && (frag.decryptdata.key == null)) {
logger.log(`Loading key for ${frag.sn} of [${levelDetails.startSN} ,${levelDetails.endSN}],level ${level}`);
this.state = State.KEY_LOADING;
hls.trigger(Event.KEY_LOADING, {frag: frag});
} else {
logger.log(`Loading ${frag.sn} of [${levelDetails.startSN} ,${levelDetails.endSN}],level ${level}, currentTime:${pos.toFixed(3)},bufferEnd:${bufferEnd.toFixed(3)}`);
// ensure that we are not reloading the same fragments in loop ...
if (this.fragLoadIdx !== undefined) {
this.fragLoadIdx++;
} else {
this.fragLoadIdx = 0;
}
if (frag.loadCounter) {
frag.loadCounter++;
let maxThreshold = config.fragLoadingLoopThreshold;
// if this frag has already been loaded 3 times, and if it has been reloaded recently
if (frag.loadCounter > maxThreshold && (Math.abs(this.fragLoadIdx - frag.loadIdx) < maxThreshold)) {
hls.trigger(Event.ERROR, {type: ErrorTypes.MEDIA_ERROR, details: ErrorDetails.FRAG_LOOP_LOADING_ERROR, fatal: false, frag: frag});
return false;
}
} else {
frag.loadCounter = 1;
}
frag.loadIdx = this.fragLoadIdx;
this.fragCurrent = frag;
this.startFragRequested = true;
this.nextLoadPosition = frag.start + frag.duration;
frag.autoLevel = hls.autoLevelEnabled;
frag.bitrateTest = this.bitrateTest;
hls.trigger(Event.FRAG_LOADING, {frag: frag});
// lazy demuxer init, as this could take some time ... do it during frag loading
if (!this.demuxer) {
this.demuxer = new Demuxer(hls,'main');
}
this.state = State.FRAG_LOADING;
return true;
}
}
set state(nextState) {
if (this.state !== nextState) {
const previousState = this.state;
this._state = nextState;
logger.log(`engine state transition from ${previousState} to ${nextState}`);
this.hls.trigger(Event.STREAM_STATE_TRANSITION, {previousState, nextState});
}
}
get state() {
return this._state;
}
getBufferRange(position) {
var i, range,
bufferRange = this.bufferRange;
if (bufferRange) {
for (i = bufferRange.length - 1; i >=0; i--) {
range = bufferRange[i];
if (position >= range.start && position <= range.end) {
return range;
}
}
}
return null;
}
get currentLevel() {
let media = this.media;
if (media) {
var range = this.getBufferRange(media.currentTime);
if (range) {
return range.frag.level;
}
}
return -1;
}
get nextBufferRange() {
let media = this.media;
if (media) {
// first get end range of current fragment
return this.followingBufferRange(this.getBufferRange(media.currentTime));
} else {
return null;
}
}
followingBufferRange(range) {
if (range) {
// try to get range of next fragment (500ms after this range)
return this.getBufferRange(range.end + 0.5);
}
return null;
}
get nextLevel() {
var range = this.nextBufferRange;
if (range) {
return range.frag.level;
} else {
return -1;
}
}
_checkFragmentChanged() {
var rangeCurrent, currentTime, video = this.media;
if (video && video.readyState && video.seeking === false) {
currentTime = video.currentTime;
/* if video element is in seeked state, currentTime can only increase.
(assuming that playback rate is positive ...)
As sometimes currentTime jumps back to zero after a
media decode error, check this, to avoid seeking back to
wrong position after a media decode error
*/
if(currentTime > video.playbackRate*this.lastCurrentTime) {
this.lastCurrentTime = currentTime;
}
if (BufferHelper.isBuffered(video,currentTime)) {
rangeCurrent = this.getBufferRange(currentTime);
} else if (BufferHelper.isBuffered(video,currentTime + 0.1)) {
/* ensure that FRAG_CHANGED event is triggered at startup,
when first video frame is displayed and playback is paused.
add a tolerance of 100ms, in case current position is not buffered,
check if current pos+100ms is buffered and use that buffer range
for FRAG_CHANGED event reporting */
rangeCurrent = this.getBufferRange(currentTime + 0.1);
}
if (rangeCurrent) {
var fragPlaying = rangeCurrent.frag;
if (fragPlaying !== this.fragPlaying) {
this.fragPlaying = fragPlaying;
this.hls.trigger(Event.FRAG_CHANGED, {frag: fragPlaying});
}
}
}
}
/*
on immediate level switch :
- pause playback if playing
- cancel any pending load request
- and trigger a buffer flush
*/
immediateLevelSwitch() {
logger.log('immediateLevelSwitch');
if (!this.immediateSwitch) {
this.immediateSwitch = true;
let media = this.media, previouslyPaused;
if (media) {
previouslyPaused = media.paused;
media.pause();
} else {
// don't restart playback after instant level switch in case media not attached
previouslyPaused = true;
}
this.previouslyPaused = previouslyPaused;
}
var fragCurrent = this.fragCurrent;
if (fragCurrent && fragCurrent.loader) {
fragCurrent.loader.abort();
}
this.fragCurrent = null;
// increase fragment load Index to avoid frag loop loading error after buffer flush
this.fragLoadIdx += 2 * this.config.fragLoadingLoopThreshold;
this.state = State.BUFFER_FLUSHING;
// flush everything
this.hls.trigger(Event.BUFFER_FLUSHING, {startOffset: 0, endOffset: Number.POSITIVE_INFINITY});
}
/*
on immediate level switch end, after new fragment has been buffered :
- nudge video decoder by slightly adjusting video currentTime (if currentTime buffered)
- resume the playback if needed
*/
immediateLevelSwitchEnd() {
let media = this.media;
if (media && media.buffered.length) {
this.immediateSwitch = false;
if(BufferHelper.isBuffered(media,media.currentTime)) {
// only nudge if currentTime is buffered
media.currentTime -= 0.0001;
}
if (!this.previouslyPaused) {
media.play();
}
}
}
nextLevelSwitch() {
/* try to switch ASAP without breaking video playback :
in order to ensure smooth but quick level switching,
we need to find the next flushable buffer range
we should take into account new segment fetch time
*/
let media = this.media;
// ensure that media is defined and that metadata are available (to retrieve currentTime)
if (media && media.readyState) {
let fetchdelay, currentRange, nextRange;
// increase fragment load Index to avoid frag loop loading error after buffer flush
this.fragLoadIdx += 2 * this.config.fragLoadingLoopThreshold;
currentRange = this.getBufferRange(media.currentTime);
if (currentRange && currentRange.start > 1) {
// flush buffer preceding current fragment (flush until current fragment start offset)
// minus 1s to avoid video freezing, that could happen if we flush keyframe of current video ...
this.state = State.BUFFER_FLUSHING;
this.hls.trigger(Event.BUFFER_FLUSHING, {startOffset: 0, endOffset: currentRange.start - 1});
}
if (!media.paused) {
// add a safety delay of 1s
var nextLevelId = this.hls.nextLoadLevel,nextLevel = this.levels[nextLevelId], fragLastKbps = this.fragLastKbps;
if (fragLastKbps && this.fragCurrent) {
fetchdelay = this.fragCurrent.duration * nextLevel.bitrate / (1000 * fragLastKbps) + 1;
} else {
fetchdelay = 0;
}
} else {
fetchdelay = 0;
}
//logger.log('fetchdelay:'+fetchdelay);
// find buffer range that will be reached once new fragment will be fetched
nextRange = this.getBufferRange(media.currentTime + fetchdelay);
if (nextRange) {
// we can flush buffer range following this one without stalling playback
nextRange = this.followingBufferRange(nextRange);
if (nextRange) {
// if we are here, we can also cancel any loading/demuxing in progress, as they are useless
var fragCurrent = this.fragCurrent;
if (fragCurrent && fragCurrent.loader) {
fragCurrent.loader.abort();
}
this.fragCurrent = null;
// flush position is the start position of this new buffer
this.state = State.BUFFER_FLUSHING;
this.hls.trigger(Event.BUFFER_FLUSHING, {startOffset: nextRange.start, endOffset: Number.POSITIVE_INFINITY});
}
}
}
}
onMediaAttached(data) {
var media = this.media = this.mediaBuffer = data.media;
this.onvseeking = this.onMediaSeeking.bind(this);
this.onvseeked = this.onMediaSeeked.bind(this);
this.onvended = this.onMediaEnded.bind(this);
media.addEventListener('seeking', this.onvseeking);
media.addEventListener('seeked', this.onvseeked);
media.addEventListener('ended', this.onvended);
let config = this.config;
if(this.levels && config.autoStartLoad) {
this.hls.startLoad(config.startPosition);
}
}
onMediaDetaching() {
var media = this.media;
if (media && media.ended) {
logger.log('MSE detaching and video ended, reset startPosition');
this.startPosition = this.lastCurrentTime = 0;
}
// reset fragment loading counter on MSE detaching to avoid reporting FRAG_LOOP_LOADING_ERROR after error recovery
var levels = this.levels;
if (levels) {
// reset fragment load counter
levels.forEach(level => {
if(level.details) {
level.details.fragments.forEach(fragment => {
fragment.loadCounter = undefined;
});
}
});
}
// remove video listeners
if (media) {
media.removeEventListener('seeking', this.onvseeking);
media.removeEventListener('seeked', this.onvseeked);
media.removeEventListener('ended', this.onvended);
this.onvseeking = this.onvseeked = this.onvended = null;
}
this.media = this.mediaBuffer = null;
this.loadedmetadata = false;
this.stopLoad();
}
onMediaSeeking() {
let media = this.media, currentTime = media ? media.currentTime : undefined, config = this.config;
logger.log(`media seeking to ${currentTime.toFixed(3)}`);
if (this.state === State.FRAG_LOADING) {
let bufferInfo = BufferHelper.bufferInfo(media,currentTime,this.config.maxBufferHole),
fragCurrent = this.fragCurrent;
// check if we are seeking to a unbuffered area AND if frag loading is in progress
if (bufferInfo.len === 0 && fragCurrent) {
let tolerance = config.maxFragLookUpTolerance,
fragStartOffset = fragCurrent.start - tolerance,
fragEndOffset = fragCurrent.start + fragCurrent.duration + tolerance;
// check if we seek position will be out of currently loaded frag range : if out cancel frag load, if in, don't do anything
if (currentTime < fragStartOffset || currentTime > fragEndOffset) {
if (fragCurrent.loader) {
logger.log('seeking outside of buffer while fragment load in progress, cancel fragment load');
fragCurrent.loader.abort();
}
this.fragCurrent = null;
this.fragPrevious = null;
// switch to IDLE state to load new fragment
this.state = State.IDLE;
} else {
logger.log('seeking outside of buffer but within currently loaded fragment range');
}
}
} else if (this.state === State.ENDED) {
// switch to IDLE state to check for potential new fragment
this.state = State.IDLE;
}
if (media) {
this.lastCurrentTime = currentTime;
}
// avoid reporting fragment loop loading error in case user is seeking several times on same position
if (this.state !== State.FRAG_LOADING && this.fragLoadIdx !== undefined) {
this.fragLoadIdx += 2 * config.fragLoadingLoopThreshold;
}
// in case seeking occurs although no media buffered, adjust startPosition and nextLoadPosition to seek target
if(!this.loadedmetadata) {
this.nextLoadPosition = this.startPosition = currentTime;
}
// tick to speed up processing
this.tick();
}
onMediaSeeked() {
logger.log(`media seeked to ${this.media.currentTime.toFixed(3)}`);
// tick to speed up FRAGMENT_PLAYING triggering
this.tick();
}
onMediaEnded() {
logger.log('media ended');
// reset startPosition and lastCurrentTime to restart playback @ stream beginning
this.startPosition = this.lastCurrentTime = 0;
}
onManifestLoading() {
// reset buffer on manifest loading
logger.log('trigger BUFFER_RESET');
this.hls.trigger(Event.BUFFER_RESET);
this.bufferRange = [];
this.stalled = false;
this.startPosition = this.lastCurrentTime = 0;
}
onManifestParsed(data) {
var aac = false, heaac = false, codec;
data.levels.forEach(level => {
// detect if we have different kind of audio codecs used amongst playlists
codec = level.audioCodec;
if (codec) {
if (codec.indexOf('mp4a.40.2') !== -1) {
aac = true;
}
if (codec.indexOf('mp4a.40.5') !== -1) {
heaac = true;
}
}
});
this.audioCodecSwitch = (aac && heaac);
if (this.audioCodecSwitch) {
logger.log('both AAC/HE-AAC audio found in levels; declaring level codec as HE-AAC');
}
this.levels = data.levels;
this.startLevelLoaded = false;
this.startFragRequested = false;
let config = this.config;
if (config.autoStartLoad) {
this.hls.startLoad(config.startPosition);
}
}
onLevelLoaded(data) {
var newDetails = data.details,
newLevelId = data.level,
curLevel = this.levels[newLevelId],
duration = newDetails.totalduration,
sliding = 0;
logger.log(`level ${newLevelId} loaded [${newDetails.startSN},${newDetails.endSN}],duration:${duration}`);
this.levelLastLoaded = newLevelId;
if (newDetails.live) {
var curDetails = curLevel.details;
if (curDetails && newDetails.fragments.length > 0) {
// we already have details for that level, merge them
LevelHelper.mergeDetails(curDetails,newDetails);
sliding = newDetails.fragments[0].start;
this.liveSyncPosition = this.computeLivePosition(sliding, curDetails);
if (newDetails.PTSKnown) {
logger.log(`live playlist sliding:${sliding.toFixed(3)}`);
} else {
logger.log('live playlist - outdated PTS, unknown sliding');
}
} else {
newDetails.PTSKnown = false;
logger.log('live playlist - first load, unknown sliding');
}
} else {
newDetails.PTSKnown = false;
}
// override level info
curLevel.details = newDetails;
this.hls.trigger(Event.LEVEL_UPDATED, { details: newDetails, level: newLevelId });
if (this.startFragRequested === false) {
// compute start position if set to -1. use it straight away if value is defined
if (this.startPosition === -1 || this.lastCurrentTime === -1) {
// first, check if start time offset has been set in playlist, if yes, use this value
let startTimeOffset = newDetails.startTimeOffset;
if(!isNaN(startTimeOffset)) {
if (startTimeOffset < 0) {
logger.log(`negative start time offset ${startTimeOffset}, count from end of last fragment`);
startTimeOffset = sliding + duration + startTimeOffset;
}
logger.log(`start time offset found in playlist, adjust startPosition to ${startTimeOffset}`);
this.startPosition = startTimeOffset;
} else {
// if live playlist, set start position to be fragment N-this.config.liveSyncDurationCount (usually 3)
if (newDetails.live) {
this.startPosition = this.computeLivePosition(sliding, newDetails);
logger.log(`configure startPosition to ${this.startPosition}`);
} else {
this.startPosition = 0;
}
}
this.lastCurrentTime = this.startPosition;
}
this.nextLoadPosition = this.startPosition;
}
// only switch batck to IDLE state if we were waiting for level to start downloading a new fragment
if (this.state === State.WAITING_LEVEL) {
this.state = State.IDLE;
}
//trigger handler right now
this.tick();
}
onKeyLoaded() {
if (this.state === State.KEY_LOADING) {
this.state = State.IDLE;
this.tick();
}
}
onFragLoaded(data) {
var fragCurrent = this.fragCurrent,
fragLoaded = data.frag;
if (this.state === State.FRAG_LOADING &&
fragCurrent &&
fragLoaded.type === 'main' &&
fragLoaded.level === fragCurrent.level &&
fragLoaded.sn === fragCurrent.sn) {
let stats = data.stats,
currentLevel = this.levels[fragCurrent.level],
details = currentLevel.details;
logger.log(`Loaded ${fragCurrent.sn} of [${details.startSN} ,${details.endSN}],level ${fragCurrent.level}`);
// reset frag bitrate test in any case after frag loaded event
this.bitrateTest = false;
// if this frag was loaded to perform a bitrate test AND if hls.nextLoadLevel is greater than 0
// then this means that we should be able to load a fragment at a higher quality level
if (fragLoaded.bitrateTest === true && this.hls.nextLoadLevel) {
// switch back to IDLE state ... we just loaded a fragment to determine adequate start bitrate and initialize autoswitch algo
this.state = State.IDLE;
this.startFragRequested = false;
stats.tparsed = stats.tbuffered = performance.now();
this.hls.trigger(Event.FRAG_BUFFERED, {stats: stats, frag: fragCurrent, id : 'main'});
this.tick();
} else {
this.state = State.PARSING;
// transmux the MPEG-TS data to ISO-BMFF segments
this.stats = stats;
let duration = details.totalduration,
start = !isNaN(fragCurrent.startDTS) ? fragCurrent.startDTS : fragCurrent.start,
level = fragCurrent.level,
sn = fragCurrent.sn,
audioCodec = this.config.defaultAudioCodec || currentLevel.audioCodec;
if(this.audioCodecSwap) {
logger.log('swapping playlist audio codec');
if(audioCodec === undefined) {
audioCodec = this.lastAudioCodec;
}
if(audioCodec) {
if(audioCodec.indexOf('mp4a.40.5') !==-1) {
audioCodec = 'mp4a.40.2';
} else {
audioCodec = 'mp4a.40.5';
}
}
}
this.pendingAppending = 0;
logger.log(`Parsing ${sn} of [${details.startSN} ,${details.endSN}],level ${level}, cc ${fragCurrent.cc}`);
let demuxer = this.demuxer;
if (!demuxer) {
demuxer = this.demuxer = new Demuxer(this.hls,'main');
}
// time Offset is accurate if level PTS is known, or if playlist is not sliding (not live)
let accurateTimeOffset = details.PTSKnown || !details.live;
demuxer.push(data.payload, audioCodec, currentLevel.videoCodec, start, fragCurrent.cc, level, sn, duration, fragCurrent.decryptdata, accurateTimeOffset);
}
}
this.fragLoadError = 0;
}
onFragParsingInitSegment(data) {
let fragCurrent = this.fragCurrent;
if (fragCurrent &&
data.id === 'main' &&
data.sn === fragCurrent.sn &&
data.level === fragCurrent.level &&
this.state === State.PARSING) {
var tracks = data.tracks, trackName, track;
// if audio track is expected to come from audio stream controller, discard any coming from main
if (tracks.audio && this.altAudio) {
delete tracks.audio;
}
// include levelCodec in audio and video tracks
track = tracks.audio;
if(track) {
var audioCodec = this.levels[this.level].audioCodec,
ua = navigator.userAgent.toLowerCase();
if(audioCodec && this.audioCodecSwap) {
logger.log('swapping playlist audio codec');
if(audioCodec.indexOf('mp4a.40.5') !==-1) {
audioCodec = 'mp4a.40.2';
} else {
audioCodec = 'mp4a.40.5';
}
}
// in case AAC and HE-AAC audio codecs are signalled in manifest
// force HE-AAC , as it seems that most browsers prefers that way,
// except for mono streams OR on FF
// these conditions might need to be reviewed ...
if (this.audioCodecSwitch) {
// don't force HE-AAC if mono stream
if(track.metadata.channelCount !== 1 &&
// don't force HE-AAC if firefox
ua.indexOf('firefox') === -1) {
audioCodec = 'mp4a.40.5';
}
}
// HE-AAC is broken on Android, always signal audio codec as AAC even if variant manifest states otherwise
if(ua.indexOf('android') !== -1 && track.container !== 'audio/mpeg') { // Exclude mpeg audio
audioCodec = 'mp4a.40.2';
logger.log(`Android: force audio codec to` + audioCodec);
}
track.levelCodec = audioCodec;
track.id = data.id;
}
track = tracks.video;
if(track) {
track.levelCodec = this.levels[this.level].videoCodec;
track.id = data.id;
}
// if remuxer specify that a unique track needs to generated,
// let's merge all tracks together
if (data.unique) {
var mergedTrack = {
codec : '',