Detect or Approximate Bluetooth Latency on Android (Audio Playback)

Question

I am currently working on an Android audio visualizer using connected smart home devices (such as Philips hue) to visualize music. I have trouble compensating the delay caused by bluetooth speakers.

I have noticed, that the Youtube app, in difference to many other video streaming apps, has almost no delay between audio and video, when using bluetooth speakers. I figure, that they must compensate for the bluetooth latency by adjusting (delaying) the video signal.

Is there a reasonable way of detecting or approximating the latency/delay of bluetooth speakers?

Thank you very much for you help!!

Best, Stefan

It seems like YouTube may be using google.github.io/ExoPlayer for playback, which has some code to detect audio latency: github.com/google/ExoPlayer/blob/master/library/src/main/java/… — Tavian Barnes
Damn, seems that's not quite enough! Their AudioTrack implementation reports positions about two seconds behind reality in my car. — Tavian Barnes
Well actually, YouTube is off by a couple seconds too in my car, so maybe that's as good as possible. — Tavian Barnes
Updated ExoPlayer link: github.com/google/ExoPlayer/blob/… - They ask android.media.AudioTrack for the getLatency method. — Henk Poley
Apart from source code strewn around the web, some documentation on AudioTrack getLatency here: developer.amazon.com/docs/fire-tv/… — Henk Poley

cuihtlauac cuihtlauac · Accepted Answer · 2016-04-16T16:51:03

This would not work for Bluetooth speakers. However, I have been able to measure the audio latency of a Bluetooth dongle using Google's Dr. Rick O'Rang loopback dongle, using Glenn Kasten test app.

Detect or Approximate Bluetooth Latency on Android (Audio Playback)

2 Answers