Video SDK for C++
- API Overview
  Agora provides ensured quality of experience (QoE) for worldwide Internet-based voice and video communications through SD-RTN™.
- IRtcEngine
  The basic interface of the Agora SDK that implements the core functions of real-time communication.
- IRtcEngineEx
  This interface class contains multi-channel methods.
- IRtcEngineEventHandler
  The SDK uses the IRtcEngineEventHandler interface to send event notifications to your app. Your app can get those notifications through methods that inherit this interface.
- IMediaPlayer
  This class provides media player functions and supports multiple instances.
- IAudioEncodedFrameObserver
  The encoded audio observer.
- IAudioDeviceManager
  Audio device management methods.
- IAudioDeviceCollection
  The IAudioDeviceCollection interface. You can get the information of audio devices with this interface.
- IVideoDeviceManager
  Video device management methods.
- IVideoDeviceCollection
  You can get the information of video devices with this interface.
- IMediaEngine
  The IMediaEngine class.
- IMediaPlayerCacheManager
  This class provides methods to manage cached media files.
- IMediaPlayerCustomDataProvider
  The callback for custom media resource files.
- IMediaPlayerSourceObserver
  Provides callbacks for media players.
- IAudioPcmFrameSink
  This class is used to get raw PCM audio.
- IAudioFrameObserverBase
  The audio frame observer.
- IAudioSpectrumObserver
  The audio spectrum observer.
- IPacketObserver
  The definition of IPacketObserver.
- IMetadataObserver
  The metadata observer.
- IVideoEncodedFrameObserver
  Receives encoded video images.
- IVideoFrameObserver
  The IVideoFrameObserver class.
- IFaceInfoObserver
  Facial information observer.
- ILocalSpatialAudioEngine
  This class calculates user positions through the SDK to implement the spatial audio effect.
- IScreenCaptureSourceList
  The IScreenCaptureSourceList class. This class is returned in the getScreenCaptureSources method.
- Struct and Enum
  This page lists all the definitions of Struct and the enums for C++.
- API Sunset Notice
  This page introduces the deprecated and deleted APIs in the SDK.

IMetadataObserver

The metadata observer.

You can call registerMediaMetadataObserver to register or unregister the IMetadataObserver object.

getMaxMetadataSize

Occurs when the SDK requests the maximum size of the metadata.

virtual int getMaxMetadataSize() { return DEFAULT_METADATA_SIZE_IN_BYTE; }

After successfully complete the registration by calling registerMediaMetadataObserver, the SDK triggers this callback once every video frame is sent. You need to specify the maximum size of the metadata in the return value of this callback.

Returns

The maximum size of the buffer of the metadata that you want to use. The highest value is 1024 bytes. Ensure that you set the return value.

onMetadataReceived

Occurs when the local user receives the metadata.

virtual void onMetadataReceived(const Metadata &metadata) = 0;

Parameters

metadata: The metadata received. See Metadata.

onReadyToSendMetadata

Occurs when the SDK is ready to send metadata.

virtual bool onReadyToSendMetadata(Metadata &metadata, VIDEO_SOURCE_TYPE source_type) = 0;

This callback is triggered when the SDK is ready to send metadata.

Attention: Ensure that the size of the metadata does not exceed the value set in the getMaxMetadataSize callback.

Parameters

source_type: Video data type. See VIDEO_SOURCE_TYPE.
metadata: The metadata that the user wants to send. See Metadata.

Returns

true: Send the video frame.
false: Do not send the video frame.