Join Tencent RTC at NAB Show 2024 in Las Vegas!
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Only  $9.9! Get 50,000 minutes with our Starter Plan, perfect for your MVP project.
Only $9.9! Get 50,000 minutes with our Starter Plan, perfect for your MVP project.
Grab It Now 
Join Tencent RTC at NAB Show 2024 in Las Vegas!
Learn more 
Only  $9.9! Get 50,000 minutes with our Starter Plan, perfect for your MVP project.
Only $9.9! Get 50,000 minutes with our Starter Plan, perfect for your MVP project.
Grab It Now 
RTC Engine
Overview
  • Web
    • Demo Quick Run
    • SDK Quick Start
    • Basic Features
      • Screen Sharing
      • Live Streaming
      • Media Device
      • Audio Volume
      • Set Encoding Profile
      • Detect Network Quality
      • Detect Capabilities
    • Advance Features
      • Enable AI Denoiser
      • Enable Audio Mixer
      • Enable Watermark
      • SEI Message
      • Custom Capturing and Rendering
      • Web Beautification Effects
    • Best Practices
      • Optimize Multi-Person Video Calls
      • Handle Autoplay Restriction
      • Handle Firewall Restriction
    • API List
    • Released Notes
    • Supported Platforms
    • Web FAQs
  • Android
    • Integration
      • 1.API Examples
      • 2.Importing the SDK
      • 3.Entering a Room
      • 4.Subscribing to Audio/Video Streams
      • 5.Publish Audio/Video Streams
      • 6.Exiting a Room
      • 7.Sensing Network Quality
      • 8.Enabling Screen Sharing
      • 9.Setting Video Quality
      • 10.Rotating Videos
    • Testing Newwork Quality
    • Custom Capturing and Rendering
    • Custom Audio Capturing and Playback
    • Client APIs
      • Overview
      • TRTCCloud
      • TRTCStatistics
      • TRTCCloudListener
      • TXAudioEffectManager
      • TXBeautyManager
      • TXDeviceManager
      • Type Definition
      • Deprecated Interface
      • Error Codes
    • Release Notes
  • iOS
    • Integration
      • 1.API Examples
      • 2.Importing the SDK
      • 3.Entering a Room
      • 4.Subscribing to Audio/Video Streams
      • 5.Publish Audio/Video Streams
      • 6.Exiting a Room
      • 7.Sensing Network Quality
      • 8.Enabling Screen Sharing
      • 9.Setting Video Quality
      • 10.Rotating Videos
    • Testing Network Quality
    • Custom Capturing and Rendering
    • Custom Audio Capturing and Playback
    • Client APIs
      • Overview
      • TRTCCloud
      • TRTCCloudDelegate
      • TRTCStatistics
      • TXAudioEffectManager
      • TXBeautyManager
      • TXDeviceManager
      • Type Definition
      • Deprecated Interface
      • ErrorCode
    • Release Notes
  • macOS
    • Integration
      • 1.API Examples
      • 2.Importing the SDK
      • 3.Entering a Room
      • 4.Subscribing to Audio/Video Streams
      • 5.Publish Audio/Video Streams
      • 6.Exiting a Room
      • 7.Sensing Network Quality
      • 8.Enabling Screen Sharing
      • 9.Sharing Computer Audio
      • 10.Setting Video Quality
      • 11.Rotating Videos
    • Testing Hardware Devices
    • Testing Network Quality
    • Custom Capturing and Rendering
    • Custom Audio Capturing and Playback
    • Client APIs
      • Overview
      • TRTCCloud
      • TRTCCloudDelegate
      • TRTCStatistics
      • TXAudioEffectManager
      • TXBeautyManager
      • TXDeviceManager
      • Type Definition
      • Deprecated Interface
      • ErrorCode
      • Release Notes
    • Release Notes
  • Windows C++
    • Integration
      • 1.API Examples
      • 2.Importing the SDK
      • 3.Entering a Room
      • 4.Subscribing to Audio/Video Streams
      • 5.Publish Audio/Video Streams
      • 6.Exiting a Room
      • 7.Sensing Network Quality
      • 8.Enabling Screen Sharing
      • 9.Setting Video Quality
      • 10.Rotating Videos
    • Testing Hardware Devices
    • Testing Network Quality
    • Custom Capturing and Rendering
    • Custom Audio Capturing and Playback
    • Client APIs
      • Overview
      • ITRTCCloud
      • ITRTCStatistics
      • TRTCCloudCallback
      • ITXAudioEffectManager
      • ITXDeviceManager
      • Type Definition
      • Deprecated Interface
      • Error Codes
    • Release Notes
  • Electron
    • Integration
      • 1.API Examples
      • 2.Importing the SDK
      • 3.Entering a Room
      • 4.Subscribing to Audio/Video Streams
      • 5.Publish Audio/Video Streams
      • 6.Exiting a Room
      • 7.Sensing Network Quality
      • 8.Enabling Screen Sharing
      • 9.Sharing Computer Audio
      • 10.Setting Video Quality
      • 11.Rotating Videos
    • Client APIs
      • Overview
      • Error Codes
  • Flutter
    • Integration
      • 1.API Examples
      • 2.Importing the SDK
      • 3.Entering a Room
      • 4.Subscribing to Audio/Video Streams
      • 5.Publish Audio/Video Streams
      • 6.Exiting a Room
      • 7.Sensing Network Quality
      • 8.Enabling Screen Sharing
      • 9.Sharing Computer Audio
      • 10.Setting Video Quality
      • 11.Rotating Videos
    • Client APIs
      • Overview
      • Error Codes
  • Unity
    • Integration
      • 1.API Examples
      • 2Importing the SDK
    • Client APIs
      • Overview
      • Error Codes
  • Qt
    • Integration
      • 1.Importing the SDK
  • Overview
    • Overview
  • Pricing
    • RTC-Engine Packages
    • Billing of On-Cloud Recording
    • Billing of MixTranscoding and Relay to CDN
    • Billing Explanation for Subscription Package Duration
    • Billing of Monitoring Dashboard
    • Free Minutes
    • Pay-As-You-Go
  • Concepts
  • Features
  • Performance Statistics
  • FAQs
    • FAQs for Beginners
    • Migration Guide
      • Twilio Video to Tencent RTC
      • Billing
      • Features
      • UserSig
      • Firewall Restrictions
      • How to Downsize Installation Package
      • TRTCCalling for Web
      • Audio and Video Quality
      • Others
RTC Engine

SEI Message

The header of a video frame has a header block called supplemental enhancement information (SEI). It is additional data inserted into the video bitstream to convey extra information. You can add a lot of information into SEI, such as parameters of the camera or encoder; time; closed captions; lyrics; and copyright info.

This tutorial mainly introduces how to send and receive SEI message in TRTC Web SDK.

Send SEI Message

You can use trtc.sendSEIMessage to send SEI message. Because the SEI is inserted to the video stream, you should call it after you started local video.
// 1. enable SEI
const trtc = TRTC.create({ enableSEI: true })
// 2. enter room & start local video
await trtc.enterRoom({ scene: 'rtc', sdkAppId, userId, userSig, roomId: 12345 })
await trtc.startLocalVideo();
// 3. send SEI
const unit8Array = new Uint8Array([1, 2, 3]);
trtc.sendSEIMessage(unit8Array.buffer);
Note
1. Supported SDK version: v5.3.0+. Supported browsers: Chrome 86+, Edge 86+, Opera 72+ browsers(Chromium Based Browser M86+).
2. Maximum 1KB(Byte) sent in a single call, maximum 30 calls per second, maximum 8KB sent per second.
3. Since SEI is sent along with video frames, there is a possibility that video frames may be lost due to poor network, and therefore SEI may be lost as well. The number of times it can be sent can be increased within the frequency limit, and the business side needs to do message de-duplication on the receiving side.
4. SEI cannot be sent without trtc.startLocalVideo and cannot be received without trtc.startRemoteVideo.
5. Only H264 encoder is supported to send and receive SEI.

Receive SEI Message

// 1. enable SEI
const trtc = TRTC.create({ enableSEI: true })
// 2. receive SEI
trtc.on(TRTC.EVENT.SEI_MESSAGE, event => {
console.log(`received sei message from ${event.userId}, data: ${event.data}, streamType: ${event.streamType}`)
})