Audio latency

Last modified by François Grisez on 2022/04/29 14:55

Devices

 Audio latency
DeviceRecorderPlayerLatency*Latency with Fast Track**
HTC 0PCV1C++C++346ms-
  LG G5 Java Java 235ms -
Java OpenSles 130ms124ms
OpenSlesOpenSles113ms-
 Nexus 6 Java Java 260ms -
JavaOpenSles155ms150ms 
OpenSles OpenSles 110ms 110ms 
Samsung S4 Mini C++ C++ 269ms -
 Samsung S5JavaJava340ms-
JavaOpenSles260ms-
OpenSlesOpenSles260ms
 Samsung S6 Java Java 270ms -
JavaOpenSles320ms123ms
OpenSlesOpenSles280ms112ms
 Samsung S7JavaJava182ms-
JavaOpenSles272ms130ms
OpenSlesOpenSles270ms-

 * Latency with the STREAM_VOICE_CALL mode
 ** To get the Fast Track we need to use STREAM_MUSIC mode instead of STREAM_VOICE_CALL. It's not a good idea because the volume control will not be the call volume, and no echo canceller.

How to check latency

Requirements

  • A computer with Audacity and a microphone
  • Linphone with the echo tester in audio settings

Use Audacity

You need to launch Audacity, launch Linphone on the device you want to test.
On Linphone click on Echo tester to run it. On Audacity, click on the rec button like here:

Rec-button.png
 

Afterwards, place your device near the microphone of your computer and make a short noise. Your computer and your device should hear this, and the device will repeat it on his speaker for the computer microphone. Stop the record and you should have a graph like that:

600px-Screen-exemple.png

To measure the latency, you need to select the beginning of the first pick to the beginning of the next pick.Select "length" and you will have the device audio latency.
600px-Screen-exemple-selection.png