Files
platform-external-webrtc/webrtc/examples/android/opensl_loopback

This directory contains an app for measuring the total delay from the native
OpenSL implementation. Note that it just loops audio back from mic to speakers.

Prerequisites:
- Make sure gclient is checking out tools necessary to target Android: your
  .gclient file should contain a line like:
  target_os = ['android']
  Make sure to re-run gclient sync after adding this to download the tools.
- Env vars need to be set up to target Android; easiest way to do this is to run
  (from the libjingle trunk directory):
  . ./build/android/envsetup.sh
  Note that this clobbers any previously-set $GYP_DEFINES so it must be done
  before the next item.
- Set up webrtc-related GYP variables:
  export GYP_DEFINES="$GYP_DEFINES java_home=</path/to/JDK>
                      enable_android_opensl=1"
- Finally, run "gclient runhooks" to generate Android-targeting .ninja files.

Example of building & using the app:

cd <path/to/repository>/trunk
ninja -C out/Debug OpenSlDemo
adb install -r out/Debug/OpenSlDemo-debug.apk