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À propos des documents
21 juin 2013, parQue faire quand un document ne passe pas en traitement, dont le rendu ne correspond pas aux attentes ?
Document bloqué en file d’attente ?
Voici une liste d’actions ordonnée et empirique possible pour tenter de débloquer la situation : Relancer le traitement du document qui ne passe pas Retenter l’insertion du document sur le site MédiaSPIP Dans le cas d’un média de type video ou audio, retravailler le média produit à l’aide d’un éditeur ou un transcodeur. Convertir le document dans un format (...) -
Modifier la date de publication
21 juin 2013, parComment changer la date de publication d’un média ?
Il faut au préalable rajouter un champ "Date de publication" dans le masque de formulaire adéquat :
Administrer > Configuration des masques de formulaires > Sélectionner "Un média"
Dans la rubrique "Champs à ajouter, cocher "Date de publication "
Cliquer en bas de la page sur Enregistrer -
Websites made with MediaSPIP
2 mai 2011, parThis page lists some websites based on MediaSPIP.
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How to play and seek fragmented MP4 audio using MSE SourceBuffer ?
29 juin 2024, par Stefan FalkNote :




If you end up here, you might want to take a look at shaka-player and the accompanying shaka-streamer. Use it. Don't implement this yourself unless you really have to.




I am trying for quite some time now to be able to play an audio track on Chrome, Firefox, Safari, etc. but I keep hitting brick walls. My problem is currently that I am just not able to seek within a fragmented MP4 (or MP3).


At the moment I am converting audio files such as MP3 to fragmented MP4 (fMP4) and send them chunk-wise to the client. What I do is defining a
CHUNK_DURACTION_SEC(chunk duration in seconds) and compute a chunk size like this :

chunksTotal = Math.ceil(this.track.duration / CHUNK_DURATION_SEC);
chunkSize = Math.ceil(this.track.fileSize / this.chunksTotal);


With this I partition the audio file and can fetch it entirely jumping
chunkSize-many bytes for each chunk :

-----------------------------------------
| chunk 1 | chunk 2 | ... | chunk n |
-----------------------------------------


How audio files are converted to fMP4


ffmpeg -i input.mp3 -acodec aac -b:a 256k -f mp4 \
 -movflags faststart+frag_every_frame+empty_moov+default_base_moof \
 output.mp4


This seems to work with Chrome and Firefox (so far).


How chunks are appended


After following this example, and realizing that it's simply not working as it is explained here, I threw it away and started over from scratch. Unfortunately without success. It's still not working.


The following code is supposed to play a track from the very beginning to the very end. However, I also need to be able to seek. So far, this is simply not working. Seeking will just stop the audio after the
seekingevent got triggered.

The code


/* Desired chunk duration in seconds. */
const CHUNK_DURATION_SEC = 20;

const AUDIO_EVENTS = [
 'ended',
 'error',
 'play',
 'playing',
 'seeking',
 'seeked',
 'pause',
 'timeupdate',
 'canplay',
 'loadedmetadata',
 'loadstart',
 'updateend',
];


class ChunksLoader {

 /** The total number of chunks for the track. */
 public readonly chunksTotal: number;

 /** The length of one chunk in bytes */
 public readonly chunkSize: number;

 /** Keeps track of requested chunks. */
 private readonly requested: boolean[];

 /** URL of endpoint for fetching audio chunks. */
 private readonly url: string;

 constructor(
 private track: Track,
 private sourceBuffer: SourceBuffer,
 private logger: NGXLogger,
 ) {

 this.chunksTotal = Math.ceil(this.track.duration / CHUNK_DURATION_SEC);
 this.chunkSize = Math.ceil(this.track.fileSize / this.chunksTotal);

 this.requested = [];
 for (let i = 0; i < this.chunksTotal; i++) {
 this.requested[i] = false;
 }

 this.url = `${environment.apiBaseUrl}/api/tracks/${this.track.id}/play`;
 }

 /**
 * Fetch the first chunk.
 */
 public begin() {
 this.maybeFetchChunk(0);
 }

 /**
 * Handler for the "timeupdate" event. Checks if the next chunk should be fetched.
 *
 * @param currentTime
 * The current time of the track which is currently played.
 */
 public handleOnTimeUpdate(currentTime: number) {

 const nextChunkIndex = Math.floor(currentTime / CHUNK_DURATION_SEC) + 1;
 const hasAllChunks = this.requested.every(val => !!val);

 if (nextChunkIndex === (this.chunksTotal - 1) && hasAllChunks) {
 this.logger.debug('Last chunk. Calling mediaSource.endOfStream();');
 return;
 }

 if (this.requested[nextChunkIndex] === true) {
 return;
 }

 if (currentTime < CHUNK_DURATION_SEC * (nextChunkIndex - 1 + 0.25)) {
 return;
 }

 this.maybeFetchChunk(nextChunkIndex);
 }

 /**
 * Fetches the chunk if it hasn't been requested yet. After the request finished, the returned
 * chunk gets appended to the SourceBuffer-instance.
 *
 * @param chunkIndex
 * The chunk to fetch.
 */
 private maybeFetchChunk(chunkIndex: number) {

 const start = chunkIndex * this.chunkSize;
 const end = start + this.chunkSize - 1;

 if (this.requested[chunkIndex] == true) {
 return;
 }

 this.requested[chunkIndex] = true;

 if ((end - start) == 0) {
 this.logger.warn('Nothing to fetch.');
 return;
 }

 const totalKb = ((end - start) / 1000).toFixed(2);
 this.logger.debug(`Starting to fetch bytes ${start} to ${end} (total ${totalKb} kB). Chunk ${chunkIndex + 1} of ${this.chunksTotal}`);

 const xhr = new XMLHttpRequest();
 xhr.open('get', this.url);
 xhr.setRequestHeader('Authorization', `Bearer ${AuthenticationService.getJwtToken()}`);
 xhr.setRequestHeader('Range', 'bytes=' + start + '-' + end);
 xhr.responseType = 'arraybuffer';
 xhr.onload = () => {
 this.logger.debug(`Range ${start} to ${end} fetched`);
 this.logger.debug(`Requested size: ${end - start + 1}`);
 this.logger.debug(`Fetched size: ${xhr.response.byteLength}`);
 this.logger.debug('Appending chunk to SourceBuffer.');
 this.sourceBuffer.appendBuffer(xhr.response);
 };
 xhr.send();
 };

}

export enum StreamStatus {
 NOT_INITIALIZED,
 INITIALIZING,
 PLAYING,
 SEEKING,
 PAUSED,
 STOPPED,
 ERROR
}

export class PlayerState {
 status: StreamStatus = StreamStatus.NOT_INITIALIZED;
}


/**
 *
 */
@Injectable({
 providedIn: 'root'
})
export class MediaSourcePlayerService {

 public track: Track;

 private mediaSource: MediaSource;

 private sourceBuffer: SourceBuffer;

 private audioObj: HTMLAudioElement;

 private chunksLoader: ChunksLoader;

 private state: PlayerState = new PlayerState();

 private state$ = new BehaviorSubject<playerstate>(this.state);

 public stateChange = this.state$.asObservable();

 private currentTime$ = new BehaviorSubject<number>(null);

 public currentTimeChange = this.currentTime$.asObservable();

 constructor(
 private httpClient: HttpClient,
 private logger: NGXLogger
 ) {
 }

 get canPlay() {
 const state = this.state$.getValue();
 const status = state.status;
 return status == StreamStatus.PAUSED;
 }

 get canPause() {
 const state = this.state$.getValue();
 const status = state.status;
 return status == StreamStatus.PLAYING || status == StreamStatus.SEEKING;
 }

 public playTrack(track: Track) {
 this.logger.debug('playTrack');
 this.track = track;
 this.startPlayingFrom(0);
 }

 public play() {
 this.logger.debug('play()');
 this.audioObj.play().then();
 }

 public pause() {
 this.logger.debug('pause()');
 this.audioObj.pause();
 }

 public stop() {
 this.logger.debug('stop()');
 this.audioObj.pause();
 }

 public seek(seconds: number) {
 this.logger.debug('seek()');
 this.audioObj.currentTime = seconds;
 }

 private startPlayingFrom(seconds: number) {
 this.logger.info(`Start playing from ${seconds.toFixed(2)} seconds`);
 this.mediaSource = new MediaSource();
 this.mediaSource.addEventListener('sourceopen', this.onSourceOpen);

 this.audioObj = document.createElement('audio');
 this.addEvents(this.audioObj, AUDIO_EVENTS, this.handleEvent);
 this.audioObj.src = URL.createObjectURL(this.mediaSource);

 this.audioObj.play().then();
 }

 private onSourceOpen = () => {

 this.logger.debug('onSourceOpen');

 this.mediaSource.removeEventListener('sourceopen', this.onSourceOpen);
 this.mediaSource.duration = this.track.duration;

 this.sourceBuffer = this.mediaSource.addSourceBuffer('audio/mp4; codecs="mp4a.40.2"');
 // this.sourceBuffer = this.mediaSource.addSourceBuffer('audio/mpeg');

 this.chunksLoader = new ChunksLoader(
 this.track,
 this.sourceBuffer,
 this.logger
 );

 this.chunksLoader.begin();
 };

 private handleEvent = (e) => {

 const currentTime = this.audioObj.currentTime.toFixed(2);
 const totalDuration = this.track.duration.toFixed(2);
 this.logger.warn(`MediaSource event: ${e.type} (${currentTime} of ${totalDuration} sec)`);

 this.currentTime$.next(this.audioObj.currentTime);

 const currentStatus = this.state$.getValue();

 switch (e.type) {
 case 'playing':
 currentStatus.status = StreamStatus.PLAYING;
 this.state$.next(currentStatus);
 break;
 case 'pause':
 currentStatus.status = StreamStatus.PAUSED;
 this.state$.next(currentStatus);
 break;
 case 'timeupdate':
 this.chunksLoader.handleOnTimeUpdate(this.audioObj.currentTime);
 break;
 case 'seeking':
 currentStatus.status = StreamStatus.SEEKING;
 this.state$.next(currentStatus);
 if (this.mediaSource.readyState == 'open') {
 this.sourceBuffer.abort();
 }
 this.chunksLoader.handleOnTimeUpdate(this.audioObj.currentTime);
 break;
 }
 };

 private addEvents(obj, events, handler) {
 events.forEach(event => obj.addEventListener(event, handler));
 }

}
</number></playerstate>

Running it will give me the following output :






Apologies for the screenshot but it's not possible to just copy the output without all the stack traces in Chrome.




What I also tried was following this example and call
sourceBuffer.abort()but that didn't work. It looks more like a hack that used to work years ago but it's still referenced in the docs (see "Example" -> "You can see something similar in action in Nick Desaulnier's bufferWhenNeeded demo ..").

case 'seeking':
 currentStatus.status = StreamStatus.SEEKING;
 this.state$.next(currentStatus); 
 if (this.mediaSource.readyState === 'open') {
 this.sourceBuffer.abort();
 } 
 break;


Trying with MP3


I have tested the above code under Chrome by converting tracks to MP3 :


ffmpeg -i input.mp3 -acodec aac -b:a 256k -f mp3 output.mp3


and creating a
SourceBufferusingaudio/mpegas type :

this.mediaSource.addSourceBuffer('audio/mpeg')


I have the same problem when seeking.


The issue wihout seeking


The above code has another issue :


After two minutes of playing, the audio playback starts to stutter and comes to a halt prematurely. So, the audio plays up to a point and then it stops without any obvious reason.


For whatever reason there is another
canplayandplayingevent. A few seconds after, the audio simply stops..



-
Hi Friends can anoye help me with my discord bot leave my voice channel before play a song
19 décembre 2020, par jojan gojanHe can find the id and the api is good he cant find all the information of youtube video but he cant play the music video idk why i search all the code and i cant find the error.


The bot was create on node.js


I stop updating this bot for 2 years idk if something has changed in the rules of discord bots


The bot was pushed to heroku but im testing the bot on my pc.


[Link to all my bot code][1]


https://wtools.io/paste-code/b2XF


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Internecine Legal Threats
1er juin 2011, par Multimedia Mike — Legal/EthicalFFmpeg and associated open source multimedia projects such as xine, MPlayer, and VLC have long had a rebel mystique about them ; a bunch of hackers playing fast and loose with IP law in order to give the world the free multimedia experience it deserved. We figured out the algorithms using any tools available, including the feared technique of binary reverse engineering. When I gave a presentation about FFmpeg at Linuxtag in 2007, I created this image illustrating said mystique :
It garnered laughs. But I made the point that we multimedia hackers just press on, doing our thing while ignoring legal threats. The policy has historically worked out famously for us– to date, I seem to be the only person on the receiving end of a sort-of legal threat from the outside world.
Who would have thought that the most credible legal threat to an open source multimedia project would emanate from a fork of that very project ? Because that’s exactly what has transpired :
Click for full threat
So it came to pass that Michael Niedermayer — the leader of the FFmpeg project — received a bona fide legal nastygram from Mans Rullgard, a representative of the FFmpeg-forked Libav project. The subject of dispute is a scorched-earth matter involving the somewhat iconic FFmpeg zigzag logo :
Original 2D logo enhanced 3D logo To think of all those years we spent worrying about legal threats from organizations outside the community. I’m reminded of that time-honored horror trope/urban legend staple : Get out ! The legal threats are coming from inside the house !
I’m interested to see how this all plays out, particularly regarding jurisdiction, as we have a U.K. resident engaging an Italian lawyer outfit to deliver a legal threat to an Austrian citizen regarding an image hosted on a server in Hungary. I suspect I know why that law firm was chosen, but it’s still a curious jurisdictional setup.
People often used to ask me if we multimedia hackers would get sued to death for doing what we do. My response was always, “There’s only one way to know for sure,” by which I meant that we would just have to engage in said shady activities and determine empirically if lawsuits resulted. So I’m a strong advocate for experimentation to push the limits. Kudos to Michael and Mans for volunteering to push the legal limits.
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