Meet Media API: C++ reference client quickstart

This page explains how to set up and run a sample using the C++ reference client implementation . To learn about the TypeScript client instead, see the TypeScript reference client quickstart .

Prerequisites

To run this quickstart, you need the following prerequisites:

• You've cloned the GitHub repository .
• A Google Cloud project with Google Meet REST API enabled.
• A Google Workspace account.

Enable the Meet REST API

Build the C++ client

The C++ implementation is built with Generate Ninja (GN) . For more information, see the WebRTC documentation .

1. Generate a password from Git at Google and configure git.

2. From your command-line interface (CLI), change <samples_location> to the directory that holds the samples and run the following command, which:

   • Changes your working directory to your home directory.
   • Creates a directory in your home directory named src .
   • Changes your working directory to src .
   • Clones https://chromium.googlesource.com/chromium/tools/depot_tools.git into the src/ directory from git.
   • Temporarily adds the ~/src/depot_tools directory to the list of locations the shell searches for executable commands.
   • Changes your working directory to the cpp directory in your samples location.
   • Runs the ./build.sh shell script.

     cd 
     
   ~
   mkdir  
   src cd 
     
   src
   git  
   clone  
   https://chromium.googlesource.com/chromium/tools/depot_tools.git export 
     
    PATH 
    = 
   ~/src/depot_tools: $PATH 
    cd 
     
   <samples_location>/cpp
   sh  
   ./build.sh 
   

Generate OAuth tokens

To connect to the Meet Media API, your app must use OAuth to generate access tokens. To learn more about accessing Google APIs with OAuth, see Using OAuth 2.0 to Access Google APIs .

You can use the OAuth 2.0 Playground to generate tokens. When using the playground, make sure to:

• Use your client ID and secret credentials from your cloud project.
• Request the correct scopes .
• Sign in to a Google Account and accept access.

Once complete, click the Exchange authorization code for tokens button and copy the generated access token.

Start a meeting

Start a meeting using the same user account that you used to generate the OAuth token. Copy the meeting code. You're now ready to run the samples.

Sample apps

The GitHub repository offers samples for receiving media and participant metadata from a meeting.

These samples collect data for a specified amount of time (default is 3 seconds) and write the collected data to files.

Audio files are in PCM16 format. Video files are in YUV420p format. These files can be played by using a library such as FFmpeg.

Because video resolutions might change during a meeting, samples include the resolution in video file names.

Participant metadata files will be human-readable text files.

Single User Media Sample

The single user media sample is a basic app that focuses on collecting audio and video. The sample doesn't determine which participant created the audio and video data. Therefore, using this sample in a meeting with more than one participant might result in corrupted output.

To run the single user media sample, run:

 $  
sh  
./run_multi.sh  
--  
 \ 
  
--meeting_space_id  
 MEETING_SPACE_ID 
  
 \ 
  
--oauth_token  
 OAUTH_TOKEN 
 

By default, a single audio file is saved to /tmp/test_output_audio.pcm .

Because video streams might change resolutions during a meeting, multiple video files might be created. Video file names will include an incrementing counter and the resolution for that file. For example, if the video stream resolution changed from 320x180 to 240x135 and then back to 320x180, the following video files would be created:

• /tmp/test_output_video_0_320x180.pcm
• /tmp/test_output_video_1_240x135.pcm
• /tmp/test_output_video_2_320x180.pcm

(Optional) Use FFmpeg to Play Output Files on Linux and Mac

FFmpeg can be used to play created audio and video files. Example commands:

  # Audio 
$  
ffplay  
-f  
s16le  
-ar  
48k  
-af  
 aformat 
 = 
 channel_layouts 
 = 
mono  
 \ 
  
/tmp/test_output_audio.pcm # Video 
 # 
 # `video_size` must match the resolution in the video filename (320x180 in 
 # this example). 
$  
ffplay  
-f  
rawvideo  
-pixel_format  
yuv420p  
-video_size  
320x180  
 \ 
  
/tmp/test_output_video_0_320x180.yuv 

Options

You can specify these options when running the samples:

Related topics

• Troubleshoot and fix Meet Media API errors

• Meet Media API data channels reference