Delay in SimpleExoPlayer to get audio from the camera

MIP
, , , ,
1

Hello,

I am using MIP SDK Mobile for Android with the example “LiveVideoSample”. I wanted to add two-way audio through “SimpleExoPlayer” where the audio that I receive from the camera arrives with 3 or 4 seconds of delay.

simple exo player 1
simple exo player 1720×372 49.9 KB

simple exo player 2
simple exo player 2678×480 65.8 KB

audio 3
audio 3630×480 60.4 KB

EDIT: Version Exoplayer ‘com.google.android.exoplayer:exoplayer:2.8.4’

Maybe someone has a solution in exoplayer with a higher version?

Any suggestions for the implemented code?

Thank you, Dario!

2

Hello Dario,

Can you please provide us with more detailed code snippets of audio implementation methods as well as with their invocations ?

Thank you in advance!

3

Krasmir, thanks for your help.

This is all the code I have for the audio implementation with exoplayer.

I use the audio properties that I saw in https://developer.milestonesys.com/s/question/0D53X00006INmfrSAD/are-there-any-live-audio-streaming-examples-for-the-mobile-sdk-now-that-support-for-this-has-been-added-in-the-2019-r3

I get fqid from the camera and with the SdkMilestone request AudioStream method I get the url that will generate the audio

Finally I use exoplayer code to generate the audio:

player = ExoPlayerFactory.newSimpleInstance(getApplicationContext(), trackSelector);
player.prepare(mediaSource);
player.addListener(new Player.EventListener() {
...
...
}

Thank you!

4

Hi Dario,

My suggestion is to use buffering strategy to lower down the delay for audio. You can pass a LoadControl parameter which holds custom buffer durations when ExoPlayer instance is being created.

For example:

   private fun initPlayer() {
        val builder = DefaultLoadControl.Builder()
 
        /*Configure the DefaultLoadControl to use our setting for how many
        Milliseconds of media data to buffer. */
        builder.setBufferDurationsMs(10, 200, 10, 10)
 
        /* Build the actual DefaultLoadControl instance */
        builder.setAllocator(DefaultAllocator(true, 1))
        loadControl = builder.createDefaultLoadControl()
 
        val trackSelector = DefaultTrackSelector(AdaptiveTrackSelection.Factory(DefaultBandwidthMeter()))
 
        player = ExoPlayerFactory.newSimpleInstance(
            this@AudioActivity,
            trackSelector,
            loadControl
        )
    }

Note: This is tested with 2.10.1 version of ExoPlayer.

Another important thing for the delay is related to the stream size. When requesting a compressed stream, the audio comes a way faster. Therefore, the delay may be caused by an internal time needed by the ExoPlayer library to process the stream.

5

Thank you very much for your answer, changing the values ​​of the setBufferDurationsMs (32*1024, 64*1024, 1024, 1024) now it works correctly.

Regards,

Dario

6

Thank you for your feedback!

I am glad it helped.

Kind regards,

Krasimir