tencent cloud

Use Cases

Cases

Online education

In the online education scenario, this solution can compose and record the audios/videos of the teacher and students during class and add other materials and AI analysis capability to restore the in-person class experience. It can also add other business features to enrich the video playback effect.

Social live streaming

During live streaming, this solution can use the stream mix recording method to mix multiple streams and relay them for audit, thereby reducing the audit costs. It can also store the recording files according to applicable regulations to meet regulatory requirements.

Financial regulation

In scenarios such as online account opening and financial audiovisual recording, this solution can record all transaction processes from a global perspective and archive the recording files to meet subsequent service or regulatory requirements.

Others

In customer service and complaint handling scenarios, this solution can record the service process and complaint content in real time, making it easier to optimize the service quality, check the reasonableness of complaints, and improve the efficiency of complaint handling.

Business process

This document describes how to use API Gateway and SCF to mix record the anchor audio/video streams in a TRTC room and upload the recording file to COS for storage. This solution provides out-of-the-box, flexible, convenient, and programmable live recording capabilities. SCF offers 512 MB of memory by default for recording file storage. If you need more storage space, you can choose to use the mount capability of CFS. The workflow is as shown below:

The recording rules are as follows:

• Up to 6 audio/video streams can be recorded.
• If there are less than 6 users in the room, streams of subsequent users entering the room will be automatically mixed. If there are more than 6 users in the room, only streams of the first 6 users entering the room will be recorded.
• If IsReserve is true, after the user exits the room, the user's stream will still be in the stream mix task, and the last frame of video image and mute will be used to complement the stream. If IsReserve is false, after the user exits the room, the user's stream will be deleted from the stream mix task. If a new user enters the room later, the new user's stream will be added to the stream mix.

The parameters for calling APIs are as follows:

// The parameters involved in CosConfig are as follows:

Note：

• UserId is the specified user ID. Idempotency is not guaranteed for multiple requests to API Gateway.
• If SecretId and SecretKey are not configured in CosConfig, the function will use the permission of the execution role SCF_ExecuteRole when accessing COS.

Trigger conditions for stopping recording:

• The TRTC room is terminated. When there is no anchor in the TRTC room for more than 300s, the room will be automatically terminated.
• The user removal API is actively called to kick the recorded user out of the room.
• To stop recording for users with RoomId, you need to call the RemoveUser API.
• To stop recording for users with StrRoomId, you need to call the RemoveUserByStrRoomId API.

After recording is stopped, the data returned by the function is as follows:

Note：

If callback is configured, after the stop, SCF will pass the returned data to the callback address in POST method.

Each item in the Files array is a JSON object as follows:

Directions

Creating function

1. Log in to the SCF console and select Function Service on the left sidebar.
2. At the top of the Function Service page, select the Guangzhou region and click Create to enter the function creating page and configure the function as shown below:
   
   • Creation method: select Template.
   • Fuzzy search: enter "TRTC", search, and select the Mix audio/video stream recording template.
     Click Learn More in the template to view relevant information in the Template Details pop-up window, which can be downloaded.
3. Click Next and configure the related information as shown below:
   
   • Function Name: the function name is automatically generated by default.
   • Async Execution: select the checkbox to enable the async execution. When it's enabled, the function will respond to the event in async execution mode. The event goes to async execution status after being invoked without waiting for the processing result.
   • Status Trace: select the checkbox to enable the status trace. When it's enabled, it will keep the logs of real-time status of response for async function events. You can query and stop the event and check the related statistics. Data of event status will be retained for three days.
   • Execution Timeout Period: it can be modified as needed.
   • Execution Role: SCF_ExecuteRole is used as the execution role by default, which grants the access permissions of QcloudCOSFullAccess and QcloudCFSFullAccess.
4. Configure an API Gateway trigger. An API service is created by default and the integration response is disabled. You can customize the trigger, but please ensure that the integration response is disabled as shown below:
   
5. Click Complete.
6. If you need to use the mount capability of CFS, as CFS can only be accessed in VPC, you should use the VPC of CFS as the VPC of the function as shown below:
   

   Note：

   To enable CFS, you need to set the environment variable CFS_PATH to a local directory, such as /mnt/audio/.

Creating TRTC application

1. Log in to the TRTC console and select Development Assistance > Demo Quick Run on the left sidebar.
2. Enter the demo name and click Create. You can choose a template for test run according to your client, such as the demo for desktop browser.
   

Testing function

1. Refer to Web to make user_00001 and user_00002 enter the TRTC room.
2. Use Postman to construct an HTTP request, where roomId is the room ID of the created TRTC application, and userId is the ID of another random user (which must be unique). Below is the sample code:

   {
     "SdkAppId": 1400000000, 
     "RoomId": 43474, 
     "UserId": "user_55952145", 
     "Mode":"12",
     "UserSig": "eJwtzNEKgkAUBNB-2efQ3e3eUqG3tMCKJJEIIxxxxxxxxxxxxxxxhvmweLWzGlUxj0mLs1GXKVf3mgrq*GFUdUR0UQrAYWDyW6Y15cwTwDm4UkxF36iXpkq1joiSc9xxxxxxxxxxxxx-S*CZeOk9sHfnEhCwlUW*fE4oWusw3dULlJ7HoSJ2e6d9fM8Y98fxUAzWA__",
     "CosConfig": {
       "Region": "ap-shanghai",
       "Bucket": "test-123456789",
       "Path": "/trtc"
       },
     "IsReserve":false,
     "Callback":"https:xxxxxxxx.com/post/xxx"        
   }
   

   See the figure below:
   
3. After the request is sent, an async function response "Async run task submitted" will be received. The RequestId of this function will be returned through x-scf-reqid in the HTTP header as shown below:
   
4. On the Function Service page in the SCF console, click the name of the function created in the Creating function step above to enter the function details page.
5. Select the Log Query tab on the function details page to view the printed recording log information as shown below:
   
6. Log in to the TRTC console and click the room ID on the Monitoring Dashboard page to view all users in the room, one of whom is the recorded user.
7. To stop recording, you can call the RemoveUser or RemoveUserByStrRoomId API to move the user out of the room.