The AudioLoopbackTest is used to test round-trip audio performance over headset jack and USB. It is based on the Loopback.apk run with Loopback dongle: https://source.android.com/devices/audio/loopback

• How to run the test?

  1. plug in the Loopback dongle to your device.
  2. make vts
  3. vts-tradefed run vts -m AudioLoopbackTest

• What metrics this test report?

  1. Average round-trip latency.
  2. Standard deviation of round-trip latency.

• Which version of Loopback.apk is used in the test? The Loopback.apk used in this test is Loopback-v17 copied from https://tradefed.teams.x20web.corp.google.com/testdata/media/apps/

• Where can I get the source code for the Loopback.apk? Internal developer: https://googleplex-android.git.corp.google.com/platform/vendor/google_toolbox/+/master/user/rago/studio/LoopbackApp/ Open source: https://github.com/gkasten/drrickorang