Test cases and test scenarios

This article provides guidance and recommendations for launching playback of Dolby Atmos and Dolby Audio content in Android Automotive media applications. Developing a detailed test plan that covers all relevant aspects remains at the discretion of developers. 

To help designing a test plan or testing an application, this article includes a list of test scenarios and test cases.

Introduction

The listed test areas include test scenarios that may help creating a test plan for a media app. Playback always proceeds without objectionable clicks, pops, or glitches. Content is played back without loosing any samples.

Basic Playback

Verify playback with relevant files and streaming formats that are supported by your app.

• Content with all channel modes that are supported by your app.
  • Dolby Digital Plus with Dolby Atmos
  • Dolby Digital Plus 7.1
  • Dolby Digital Plus 5.1
  • Dolby Digital Plus stereo
• Dolby Atmos playback with different bitrates.
  • 256 kbit/s
  • 448 kbit/s
  • 768 kbit/s
• Streaming input formats that applies to your service(s).
  • DASH
  • HLS
  • progressive mp4

Audio Routing

The Dolby Automotive Emulator Image plays only mono audio for Dolby Atmos content, not full multichannel sound. You can dump, i.e. extract the audio data into a WAV file, and verify that the audio sequence works and to hear full Dolby Atmos audio and test your player. This can preferably be done with the channel identification test.

• Verify that the audio is correctly routed and that the channel order is correct.
  • Content with channel identification, Dolby Digital Plus with Dolby Atmos 
    • Channel ID 7.1.4
    • Channel ID 5.1.4

Detailed instructions

Dump the audio using the following steps and commands:

Step 1: Start the emulator.

Step 2: Set up the emulator for audio dumping.

adb root
adb shell setenforce 0
adb shell setprop "vendor.dolby.dcx.mixer" 1
adb shell rm -f /data/vendor/dolby/car*

Step 3: Play your Dolby Atmos content using your application.

Step 4: Get the audio file. Run this command to copy the dumped audio to your computer:

adb pull /data/vendor/dolby .

Note: The pulled WAV file is placed in a subfolder called dolby.

Step 5: Verify the channel order with a WAV file analyzer.

The dumped audio file may have different channel ordering. For 7.1.x output configurations, the channel order differs between Android and the Dolby Car Experience Implementation:

• Android channel order: Left, Right, Center, LFE (Low Frequency Effect), Left Back (Lb), Right Back (Rb), Left Surround (Ls), Right Surround (Rs)
• Dolby Car Experience Implementation channel order: L, R, C, LFE, Ls, Rs, Lb, Rb

When testing your audio, account for this difference in the Back and Surround channel positions.

Example of an 7.1.4 output from using a WAV file analyzer. Android channel order is expected from the dumped audio.

System Interaction

1. Verify that operating controls repeatedly does not cause any issues, e.g. any objectionable clicks, pops, or glitches during playback of Dolby Atmos content. Examples of operating controls are: 
   1. Play/Pause
   2. Seek
   3. Stop
   4. Next/Previous
2. Verify that concurrent audio interactions are reproduced correctly during playback of Dolby Atmos content. Playback of Dolby Atmos content may be muted, ducked, or paused during the concurrent audio interaction. Examples of concurrent audio interactions are:
   1. System sounds
   2. Navigation
   3. Incoming calls
   4. Notifications
3. Verify that the Voice User Interface works correctly during playback of Dolby Atmos content. Playback of Dolby Atmos content may be muted, ducked, or paused during the interaction with the voice UI.

UI Indication

To test the correct indication of Dolby content in templated media apps, install and run your application with Android Automotive with Google APIs x86_64 System Image (Build Number: sdk_gcar_x86_64-userdebug 14 UAA1.250512.001 13479943 dev-keys).

To get the image file, proceed as follows:

1. Go to SDK manager → SDK Platforms.
2. Select Show package details.
3. Go to Android 14.0 ("UpsideDownCake").
4. Select Android Automotive with Google APIs x86_64 System Image.
5. Select OK to download.
6. Go to Device Manager → Create Virtual Device.
7. Select Automotive; the device must not have "play store" → next.
8. On the Recommended tab, select the "UpsideDownCake" API 34 Android 14 image.
9. Click Finish.

• Verify that Dolby Atmos and Dolby Audio content (if applicable) is correctly indicated on the UI of the the application during playback. See the following resources for more details:
  • UI/UX Guidelines and the zipped logo files, downloadable from here.
  • A guide how to modify the code: https://professionalsupport.dolby.com/s/article/Support-Dolby-Atmos-in-Android-Automotive-OS-media-apps?language=en_US, see section Indicating Dolby Atmos and Dolby Audio Content.

Format Switching

1. Verify transitions between Dolby content to non-Dolby content.
2. Verify the continuity of the output format when the input format changes (if applicable). This also applies to audio codec mode changes (for example, Dolby Digital Plus without Dolby Atmos vs Dolby Digital Plus with Dolby Atmos).
3. Verify that the device switches back to Dolby Atmos playback after non-Dolby content has been played or after the app has lost focus to a different app.
4. Verify that the Dolby Atmos and Dolby Audio content is correctly indicated in the UI when transitioning from non-Dolby Content. During playback of non-Dolby content, there must not be a Dolby indication.

Loudness Consistency

• Verify that the application maintains a consistent average loudness during any operation. 
• Verify that this works regardless of whether the audio input is in a Dolby or a non-Dolby format.

For A/V streaming services: Audio/video synchronization

A/V synchronization is required to be tested in a complete product set up. Streamable A/V test signals are available for testing purposes. While designed primarily for A/V sync testing, these signals can also be used to evaluate other areas such as basic playback functionality.  

The video playback might be impacted due to the performance of the emulator and/or local machine.

Screen sizes

Verify that your app is working as expected on different screen sizes.

Detailed instructions

The following commands can be used to test how your app looks on different screens: 

adb shell wm density [number]

adb shell wm size [width]x[height]

Replace [number] with a density value and [width]x[height] with screen dimensions.