Add or remove playlist items (MediaSources)

[dckristiono]

I use exoplayer dev-v2, I need function to add or remove playlist items (media sources) without release player or initialize player.
Can you make this function?

thanks!

[ojw28]

It's pretty easy to implement the first request yourself (create a class a bit like ConcatenatingMediaSource, but with the ability to add/remove). We should be providing a standard component for this. Let's use this issue to track.

Please file a separate enhancement request for the other request; the two aren't related.

[dckristiono]

do you finish to make this function?

[calulelalu]

Hi, I'm trying to implement a DynamicConcatenatingMediaSource class close to ConcatenatingMediaSource, except for the Lists management instead of arrays for mediasources, timelines and manifests and adding the following addSource method:

public void addSource(MediaSource mediaSource) {
    this.mediaSources.add(mediaSource);
    duplicateFlags = buildDuplicateFlags(this.mediaSources);
}

I receive the following exception when I seek to the last-1 track (before the one I added):
Unexpected exception loading stream
java.lang.NullPointerException at com.google.android.exoplayer2.source.ExtractorMediaSource.onSourceInfoRefreshed(ExtractorMediaSource.java:181)

What am I missing?

Thank you!

[calulelalu]

I eventually found the problem (yeah!).
The issue, described in this stackoverflow https://stackoverflow.com/questions/39612004/dynamic-playlists-with-exoplayer-2/39725741#39725741
was with the replacement of the arrays to lists.

To add new sources in my DynamicConcatenatingMediaSources:

public void addSource(MediaSource mediaSource) {
    this.mediaSources.add(mediaSource);
    duplicateFlags = buildDuplicateFlags(this.mediaSources);
    if(!mediaSources.isEmpty())
        prepareSource(mediaSources.size() -1);
}

[calulelalu]

Now I'm stuck on the remove issue... any help?
Performing

public void removeSource(int position){
    MediaSource removedMediaSource = this.mediaSources.remove(position);
}

obviously does not update all the lists and Periods references but I'm losing into the code and not able to figure out what is to be done.

[ascmartins]

I had this working but since I moved to version r2.0.4 it only plays first video and the appended ones causes player to be in idle or end state. The only change I needed to do was refactoring the override method createPeriod from
@Override public MediaPeriod createPeriod(int index, Callback callback, Allocator allocator, long positionUs)
to
@Override public MediaPeriod createPeriod(int index, Allocator allocator, long positionUs)

Since this change all stopped working. Any idea what can cause the issue? Anyone can give me a light what callback does?

[marwanf1]

Hello, any updates on this issue?

If not, is there any reference on how to implement the remove part?

Thanks

[ascmartins]

@marwanf1 take a look at issue #2097 and see if the AppendingMediaSource.java class can help you. In addition, to make this work for me I had to make the changes commented on 28 Nov 2016 (referred thread)

[BubuKunz]

AppendingMediaSource.java is very helpfull, but exist one problem: in method appendSource you use method removeFirstMediaSource() if count of MediaSources bigger then 2. With this method nothing work. I tried to increase the max size of lists (up to 10) and items had been adding (during playing) successfully. But when i added 11-th item, it not played. When i removed method removeFirstMediaSource(), i can adding as much MediaSources as i want, but i care about StackOverFlow or something also. Can you help me with this?
According to my issue i must playing a few short videos in random order endlessly

[ascmartins]

Hi. Sorry no referring that, but I quit using the removeFirstMediaSource() method. I am using about 8000 videos/day and it works fine. I restart app at 00:00 each day, maybe you can do same thing if you need it run endlessly. I've been watching memory during play, it changes on each movie transaction, up or down according to video resolution. My app has been up and running for a week without stack overflow. Seems like when adding a media source what happens is that Exoplayer adds video to time line to load it as fast as possible when previous video ends.
But in order for this to as I expected I had to add the line renderer.resetPosition(0); in ExoPlayerImplInternal.java on ExoPlayer library, otherwise it won't start next videos.

[BubuKunz]

Okay, i understand, thank you

[AOrobator]

@ascmartins Did you ever make a MediaSource that can also remove items?

@ojw28 In issue #2097, you suggested exposing a Timeline that creates Periods. To create a Period you'll have to know the corresponding MediaSource, assuming that every Period has exactly one MediaSource. What's the best way to obtain a mapping between Periods and MediaSources? Do you have any other suggestions or best practices for implementing this?

[ascmartins]

Hello @AOrobator !
I didn't implement anything else than posted above. So I don't have it removing MediaSources from list.

[b0g8]

@calulelalu , @tonihei , did you manage to get a MediaSource where items can be removed/swaped without releasing the player?

[calulelalu]

Hi, unfortunately not, I had to manage the playlist by myself externally from exoplayer.

[tonihei]

@b0g8, We are going to work on this topic soon to provide a build-in solution for a media source which supports adding/removing. Subscribe to this thread and you'll get informed as soon as we are ready :)

[b0g8]

@tonihei, is this on hold?

[tonihei]

No, still working on it. It is currently undergoing internal reviews.

[oikmar]

@tonihei any approximate ETA on this. not a specific date, but in terms of time frame: day(s), week(s), month(s)?

[tonihei]

@oikmar Days, most likely.

[AOrobator]

@tonihei When this is implemented, will gapless playback be supported?

[tonihei]

@AOrobator Gapless playback is already supported when you use ConcatenatingMediaSource.

[AOrobator]

@tonihei I understand that ConcatenatingMediaSource supports gapless playback. I would assume that when this PlaylistMediaSource gets implemented it would also support gapless playback by extension, but I just wanted to clarify instead of assuming.

[tonihei]

We finished working on the DynamicConcatenatingMediaSource by now. You'll find it in the dev branch. It works exactly the same as the ConcatenatingMediaSource but also offers methods to add, remove, and access media sources during playback.

[magillus]

That is great news! Thank you!

…

On Tue, Jul 4, 2017, 2:04 PM tonihei ***@***.***> wrote: We finished working on the DynamicConcatenatingMediaSource <https://github.com/google/ExoPlayer/blob/dev-v2/library/core/src/main/java/com/google/android/exoplayer2/source/DynamicConcatenatingMediaSource.java> by now. You'll find it in the dev branch. It works exactly the same as the ConcatenatingMediaSource but also offers methods to add, remove, and access media sources during playback. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#1706 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAsiywGFA_XfUaM6ezGQ5EAd22C-V-z8ks5sKipCgaJpZM4JZHMi> .

[ursusursus]

Hi, do you provide some snapshot builds of dev branch or do I have to checkout sources / wait for stable release?

[tonihei]

Yes, you're right. Until we merge this change into our release branch, you would either need to check out the sources or wait for the release.

[AOrobator]

@ursusursus I've built an aar off the develop branch that I've been playing around with that has DynamicConcatenatingMediaSource merged in. You can include it in your project by putting the aar file in your libs folder then adding the following line to your app level build.gradle file

compile(name: "library-core-release", ext: "aar")

library-core-release.aar.zip

[mirandole]

Hello @tonihei,

Do you know when the DynamicConcatenatingMediaSource class will be merged on master ? And when will it be available on Gradle ?

Thank you very much for your work !

[ojw28]

Probably a couple of weeks. It'll be available in the 2.5 release. Thanks.

[mirandole]

Hello @AOrobator !

Thank you for your .aar file.
I've added your aar to my app. Gradle sync well. But I can't find any DynamicConcatenatingMediaSource class in my app.

Do you know how I could get it ?

[AOrobator]

@mirandole try a clean build? Make sure you're spelling it correctly? It's in the aar and I'm using it in a project of mine, so I know it works

[mirandole]

@AOrobator I've extrat .aar and add the classes .jar file to my build.gradle app with this line :

compile files('libs/exoplayer-dev-v2-snapshot')

Now everything works well.

Thank you

[mirandole]

Hello @tonihei @ojw28 @AOrobator !

My app crash when I prepare Exoplayer with a DynamicConcatenatingMediaSource.
But everything works fine using ConcatenatingMediaSource.

Source Code :

private void testSimple(Metadatas metadatas) {
        if(this.dynamicConcatenatingMediaSource != null) {
            this.dynamicConcatenatingMediaSource.releaseSource();
        }
        this.dynamicConcatenatingMediaSource = new DynamicConcatenatingMediaSource();
        MediaSource ms1 = new ExtractorMediaSource(Uri.parse(metadatas.getResolvedStreamUrl()), dataSourceFactory, extractorsFactory, null, null);
        MediaSource ms2 = new ExtractorMediaSource(Uri.parse(metadatas.getResolvedStreamUrl()), dataSourceFactory, extractorsFactory, null, null);
        dynamicConcatenatingMediaSource.addMediaSource(ms1);
        dynamicConcatenatingMediaSource.addMediaSource(ms2);

        exoPlayer.prepare(this.dynamicConcatenatingMediaSource);

        //this.concatenatingMediaSource = new ConcatenatingMediaSource(ms1, ms2);
        //exoPlayer.prepare(this.concatenatingMediaSource);
    }

Log

FATAL EXCEPTION: ExoPlayerImplInternal:Handler
                                                   Process: PID: 21073
                                                   java.lang.AbstractMethodError: abstract method "com.google.android.exoplayer2.source.MediaPeriod com.google.android.exoplayer2.source.MediaSource.createPeriod(int, com.google.android.exoplayer2.upstream.Allocator, long)"
                                                       at com.google.android.exoplayer2.ExoPlayerImplInternal$MediaPeriodHolder.<init>(ExoPlayerImplInternal.java:1472)
                                                       at com.google.android.exoplayer2.ExoPlayerImplInternal.maybeUpdateLoadingPeriod(ExoPlayerImplInternal.java:1289)
                                                       at com.google.android.exoplayer2.ExoPlayerImplInternal.updatePeriods(ExoPlayerImplInternal.java:1138)
                                                       at com.google.android.exoplayer2.ExoPlayerImplInternal.doSomeWork(ExoPlayerImplInternal.java:460)
                                                       at com.google.android.exoplayer2.ExoPlayerImplInternal.handleMessage(ExoPlayerImplInternal.java:308)
                                                       at android.os.Handler.dispatchMessage(Handler.java:98)
                                                       at android.os.Looper.loop(Looper.java:154)
                                                       at android.os.HandlerThread.run(HandlerThread.java:61)`


Everything works fine with `ConcatenatingMediaSource

[ojw28]

That looks like an issue with the way you're building and including the code. If you want to depend on the dev-v2 branch you should really do so properly by following the instructions under "Locally" in the README.

[mirandole]

Thank you that solved my problem.

[mirandole]

Hello @ojw28

DynamicConcatenatingMediaSource works well to play several tracks with gapless.
But I need to refresh metadatas of the current track playing on Exoplayer. To do that I need to know when exoplayer has completed the current playing track and started the next one.

It seems that I can't use playbackstate listener because STATE_ENDED with DynamicConcatenatingMediaSource until i've played all the playlist tracks.

How can I know if the current track is completed and the next one started to always get current track playing metadatas on my front activity screen ?

Thank you very much.

[ursusursus]

@mirandole onPositionDiscontinuity (from memory) is the callback you want

[mirandole]

Thanks @ursusursus but it could be a seekTo discontinuity, right ? Could discontinuity come from other things that a track change ? Because I can only verify if discontinuity comes from a seek, I can't verify for other event that produce onPositionDiscontinuity. I don't know them.

[andrewlewis]

To detect advancing from window (playlist item) to the next, handle onPositionDiscontinuity and check for the current window index returned by player.getCurrentWindowIndex() having changed since the last call.

Several things can cause a discontinuity: (1) advancing from one window (playlist item) to the next, (2) advancing from one period to the next (which is different from (1) for multi-period windows), (3) seeking and (4) source-initiated discontinuities (for example, when the source retries loading due to an error, but has to move the playback position).

[AOrobator]

@mirandole I've been using onTracksChanged() with success as it's a bit more specific to our use case. You just have to keep track of how many tracks have played because the first time it's called, it's with the first track.

@andrewlewis @ojw28 curious to get your thoughts on my approach

[tonihei]

onTracksChanged is only triggered when the available or selected tracks change. For example, this could be a switch between different video resolutions in an adaptive media source, activating or deactivating audio or video, or similar things. When playback advances to the next playlist item this method might or might not be called depending on the available tracks in the both items.

We recommend to use onPositionDiscontinuity to get notified of any changes to the currently playing window (playlist item) as @andrewlewis already pointed out.

[mirandole]

Thank you @AOrobator @tonihei .
It works well with onPositionDiscontinuity

Unfortunately, it seems that DynamicConcatenatingMediaSource mp3 track transition isn't truly gapless.
I still hear a very small gap between tracks of albums. Superpoze artist Opening album is a good one to gapless test. I probably did something wrong.

Did someone succeed in playing mp3 or FLAC tracks album gapless?

[AOrobator]

I'm also confirming that I hear a small gap between tracks when using DynamicConcatenatingMediaSource. I guess it's probably best to create another issue, then link it here. @mirandole

[tonihei]

Yes, please create a new issue with steps to reproduce your problem. Thanks!

[keyboardr]

It looks like ExoPlayer.getDuration() doesn't work with DynamicConcatenatingMediaSource, even after calling prepare(). Is there a way to get a queued MediaSource's duration (and seek to a position) before setPlayWhenReady(true) is called?

[tonihei]

Please create a new issue using the issue template if you think something is wrong. Thank you!

[keyboardr]

I don't necessarily think there is anything wrong. It might just be my own lack of understanding how DeferredTimeline is expected to work. I'll file a bug just in case.