OboeTester can be used to measure the round trip latency and glitches. It can be launched from a shell script by using an Android Intent.
Before running the app from an Intent, it should be launched manually and a Round Trip Latency test run. Then you can give permission for using the microphone to record the looped back sound, and give permission to write to external storage for saving the test result.
All tests require:
The latency, glitch and data_paths tests also need:
* If you don't have a 3.5 mm jack then you can use a USB-C to 3.5mm adapter. In order to use ADB at the same time you will also need a USB switching device or use ADB/Wifi. Internally at Google, the TigerTail device can be used for USB.
The app can be started by sending a Start comment to the OboeTester class. The app will run and the results will be written to a file.
adb shell am start -n com.mobileer.oboetester/.MainActivity {parameters}
String parameters are sent using:
--es {parameterName} {parameterValue}
For example:
--es test latency
Integer parameters are sent using:
--ei {parameterName} {parameterValue}
For example:
--ei buffer_bursts 8
Boolean parameters are sent using:
--ez {parameterName} {parameterValue}
For example:
--ez use_input_devices false
There are two required parameters for all tests:
--es test {latency, glitch, data_paths, input, output}
The "latency" test will perform a Round Trip Latency test.
It will request EXCLUSIVE mode for minimal latency.
The "glitch" test will perform a single Glitch test.
The "data_paths" test will verify input and output streams in many possible configurations.
The "input" test will open and start an input stream.
The "output" test will open and start an output stream.
--es file {full path for resulting file} // We recommend using the "/sdcard/Download" folder
There are some optional parameter in common for all tests:
--ef volume {volume} // normalized volume in the range of 0.0 to 1.0
--es volume_type {"accessibility", "alarm", "dtmf", "music", "notification", "ring", "system", "voice_call"}
Stream type for the setStreamVolume() call. Default is "music".
--ez background {"true", 1, "false", 0} // if true then Oboetester will continue to run in the background
There are several optional parameters in common for glitch, latency, input, and output tests:
--ei buffer_bursts {bursts} // number of bursts in the buffer, 2 for "double buffered"
--es in_api {"unspecified", "opensles", "aaudio"} // native input API, default is "unspecified"
--es out_api {"unspecified", "opensles", "aaudio"} // native output API, default is "unspecified"
--es in_channel_mask {"mono", "stereo", "2.1", "tri", "triBack", "3.1", "2.0.2", "2.1.2", "3.0.2", "3.1.2", "quad", "quadSide", "surround", "penta", "5.1", "5.1Side", "6.1", "7.1", "5.1.2", "5.1.4", "7.1.2", "7.1.4", "9.1.4", "9.1.6", "frontBack"}
--es out_channel_mask {"mono", "stereo", "2.1", "tri", "triBack", "3.1", "2.0.2", "2.1.2", "3.0.2", "3.1.2", "quad", "quadSide", "surround", "penta", "5.1", "5.1Side", "6.1", "7.1", "5.1.2", "5.1.4", "7.1.2", "7.1.4", "9.1.4", "9.1.6", "frontBack"}
--ei in_channels {samples} // number of input channels, default is 2. This is ignored if in_channel_mask is set.
--ei out_channels {samples} // number of output channels, default is 2. This is ignored if out_channel_mask is set.
--ei sample_rate {hertz}
--es in_perf {"none", "lowlat", "powersave"} // input performance mode, default is "lowlat"
--es out_perf {"none", "lowlat", "powersave"} // output performance mode, default is "lowlat"
--es in_sharing {"shared", "exclusive"} // input sharing mode, default is "exclusive"
--es out_sharing {"shared", "exclusive"} // output sharing mode, default is "exclusive"
--ez in_use_mmap {"true", 1, "false", 0} // if true then MMAP is allowed, if false then MMAP will be disabled
--ez out_use_mmap {"true", 1, "false", 0} // if true then MMAP is allowed, if false then MMAP will be disabled
There are some optional parameters in common for glitch, input, and output tests:
--ei duration {seconds} // glitch test duration, default is 10 seconds
There are several optional parameters for just the “glitch” test:
--ef tolerance {tolerance} // amount of deviation from expected that is considered a glitch
// Range of tolerance is 0.0 to 1.0. Default is 0.1. Note use of "-ef".
// input preset, default is "voicerec"
--es in_preset ("generic", "camcorder", "voicerec", "voicecomm", "unprocessed", "performance"}
There are several optional parameters for just the “data_paths” test:
--ez use_input_presets {"true", 1, "false", 0} // Whether to test various input presets. Note use of "-ez"
--ez use_input_devices {"true", 1, "false", 0} // Whether to test various input devices. Note use of "-ez"
--ez use_output_devices {"true", 1, "false", 0} // Whether to test various output devices. Note use of "-ez"
--ei single_test_index {testId} // Index for testing one specific test
There are some optional parameters for just the “output” test:
--es signal_type {sine, sawtooth, freq_sweep, pitch_sweep, white_noise} // type of sound to play, default is sine
For example, a complete command for a “latency” test might be:
adb shell am start -n com.mobileer.oboetester/.MainActivity \
--es test latency \
--es file /sdcard/Download/latency20190903.txt \
--ei buffer_bursts 2 \
--ef volume 0.8 \
--es volume_type music \
--ei buffer_bursts 2 \
--ei out_channels 1
or for a “glitch” test:
adb shell am start -n com.mobileer.oboetester/.MainActivity \
--es test glitch \
--es file /sdcard/Download/glitch20190903.txt \
--es in_perf lowlat \
--es out_perf lowlat \
--es in_sharing exclusive \
--es out_sharing exclusive \
--ei buffer_bursts 2 \
--ei sample_rate 48000 \
--ef tolerance 0.123 \
--ei in_channels 2 \
or for a “data_paths” test:
adb shell am start -n com.mobileer.oboetester/.MainActivity \
--es test data_paths \
--es file /sdcard/data_paths20190903.txt
--ez use_input_presets true
--ez use_input_devices false
--ez use_output_devices true
Test results are simple files with “name = value” pairs. The test results can be obtained using adb pull.
adb pull /sdcard/test20190611.txt .
The beginning of the report is common to latency and glitch tests:
build.fingerprint = google/bonito/bonito:10/QP1A.190711.017/5771233:userdebug/dev-keys test.version = 1.5.10 test.version.code = 19 time.millis = 1567521906542 in.channels = 2 in.perf = lowlat in.sharing = exclusive in.api = aaudio in.rate = 48000 in.device = 30 in.mmap = yes in.burst.frames = 96 in.xruns = 0 out.channels = 2 out.perf = lowlat out.sharing = exclusive out.api = aaudio out.rate = 48000 out.device = 27 out.mmap = yes out.burst.frames = 96 out.buffer.size.frames = 192 out.buffer.capacity.frames = 3072 out.xruns = 0
Each test also adds specific value. For “latency”. If the test fails then some values will be unavailable.
Here is a report from a good test. The ‘#’ comments were added for this document and are not in the report.
rms.signal = 0.81829 # Root Mean Square of the signal, if it can be detected rms.noise = 0.12645 # Root Mean Square of the background noise before the signal is detected reset.count = 2 # number of times the full duplex stream input underflowed and had to resynchronize result = 0 # 0 or a negative error result.text = OK # text equivalent of the result latency.empty.frames = 476 # round trip latency if the top output buffer was empty latency.empty.msec = 9.92 # same but translated to milliseconds latency.frames = 668 # round trip latency as measured latency.msec = 13.92 # same but translated to milliseconds, "pro-audioo" devices should be <=20 msec confidence = 0.959 # quality of the latency result between 0.0 and 1.0, higher is better
Here is a report from a test that failed because the output was muted. Note the latency.msec is missing because it could not be measured.
rms.signal = 0.00000 rms.noise = 0.00048 reset.count = 3 result = -96 result.text = ERROR_CONFIDENCE confidence = 0.009
Here is a report from a good test. The ‘#’ comments were added for this document and are not in the report.
tolerance = 0.123 state = LOCKED unlocked.frames = 2528 # frames spent trying to lock onto the signal locked.frames = 384084 # frames spent locked onto a good signal with no glitches glitch.frames = 0 # frames spent glitching or recovering from a glitch reset.count = 208 # number of times the full duplex stream input underflowed and had to resynchronize peak.amplitude = 0.057714 # peak amplitude of the input signal, between 0.0 and 1.0 signal.noise.ratio.db = 96.3 time.total = 9.96 seconds # close to your specified duration time.no.glitches = 9.96 # time we have been running with no glitches max.time.no.glitches = 9.96 # max time with no glitches glitch.count = 0 # number of glitch events, actual number may be higher if close together
Here is a report from a test that failed because the output was muted. Note the glitch.count is missing because it could not be measured.
state = WAITING_FOR_SIGNAL unlocked.frames = 0 locked.frames = 0 glitch.frames = 0 reset.count = 1 time.total = 9.95 seconds
The report first goes through the info about the specific device before going through input preset tests, input devices tests, and output tests. Each will show the specific configuration of a test before showing whether it passed or failed. At the end of the report, an analysis of the failed tests will be given followed by the number of passed, failed, and skipped tests.