IAudioFrameObserverBase

AUDIO_FRAME_TYPE

Audio frame type.

Enumerator

FRAME_TYPE_PCM16: 0: PCM 16

AudioFrame

Raw audio data.

  struct AudioFrame {
    AUDIO_FRAME_TYPE type;
    int samplesPerChannel;
    agora::rtc::BYTES_PER_SAMPLE bytesPerSample;
    int channels;
    int samplesPerSec;
    void* buffer;
    int64_t renderTimeMs;
    int avsync_type;

    AudioFrame() : type(FRAME_TYPE_PCM16),
                   samplesPerChannel(0),
                   bytesPerSample(rtc::TWO_BYTES_PER_SAMPLE),
                   channels(0),
                   samplesPerSec(0),
                   buffer(NULL),
                   renderTimeMs(0),
                   avsync_type(0),
  };

Attributes

type

The type of the audio frame. See AUDIO_FRAME_TYPE.

samplesPerChannel

The number of samples per channel in the audio frame.

bytesPerSample

The number of bytes per sample. The number of bytes per audio sample, which is usually 16-bit (2-byte).

channels

The number of audio channels (the data are interleaved if it is stereo).

1: Mono.
2: Stereo.

samplesPerSec

The number of samples per channel in the audio frame.

buffer

The data buffer of the audio frame. When the audio frame uses a stereo channel, the data buffer is interleaved.

The size of the data buffer is as follows: buffer = samples × channels × bytesPerSample.

renderTimeMs

The timestamp (ms) of the external audio frame.

You can use this timestamp to restore the order of the captured audio frame, and synchronize audio and video frames in video scenarios, including scenarios where external video sources are used.

avsync_type

Reserved for future use.

onEarMonitoringAudioFrame

Gets the in-ear monitoring audio frame.

virtual bool onEarMonitoringAudioFrame(AudioFrame& audioFrame) = 0;

In order to ensure that the obtained in-ear audio data meets the expectations, Agora recommends that you choose one of the following two methods to set the in-ear monitoring-ear audio data format:

Method 1: After calling setEarMonitoringAudioFrameParameters to set the audio data format and registerAudioFrameObserver to register the audio frame observer object, the SDK calculates the sampling interval according to the parameters set in the methods, and triggers the onEarMonitoringAudioFrame callback according to the sampling interval.
Method 2: After calling registerAudioFrameObserver to register the audio frame observer object, set the audio data format in the return value of the getObservedAudioFramePosition callback. The SDK then calculates the sampling interval according to the return value of the getEarMonitoringAudioParams callback, and triggers the onEarMonitoringAudioFrame callback according to the sampling interval.

Note:

The priority of method 1 is higher than that of method 2. If method 1 is used to set the audio data format, the setting of method 2 is invalid.

Parameters

audioFrame: The raw audio data. See AudioFrame.

Returns

Without practical meaning.

onMixedAudioFrame

Retrieves the mixed captured and playback audio frame.

virtual bool onMixedAudioFrame(const char* channelId, AudioFrame& audioFrame) = 0;

To ensure that the data format of mixed captured and playback audio frame meets the expectations, Agora recommends that you choose one of the following two ways to set the data format:

Method 1: After calling setMixedAudioFrameParameters to set the audio data format and registerAudioFrameObserver to register the audio frame observer object, the SDK calculates the sampling interval according to the parameters set in the methods, and triggers the onMixedAudioFrame callback according to the sampling interval.
Method 2: After calling registerAudioFrameObserver to register the audio frame observer object, set the audio data format in the return value of the getObservedAudioFramePosition callback. The SDK then calculates the sampling interval according to the return value of the getMixedAudioParams callback, and triggers the onMixedAudioFrame callback according to the sampling interval.

Note:

The priority of method 1 is higher than that of method 2. If method 1 is used to set the audio data format, the setting of method 2 is invalid.

Parameters

audioFrame: The raw audio data. See AudioFrame.
channelId: The channel ID.

Returns

Without practical meaning.

onPlaybackAudioFrame

Gets the raw audio frame for playback.

virtual bool onPlaybackAudioFrame(const char* channelId, AudioFrame& audioFrame) = 0;

To ensure that the data format of audio frame for playback is as expected, Agora recommends that you choose one of the following two methods to set the audio data format:

Method 1: After calling setPlaybackAudioFrameParameters to set the audio data format and registerAudioFrameObserver to register the audio frame observer object, the SDK calculates the sampling interval according to the parameters set in the methods, and triggers the onPlaybackAudioFrame callback according to the sampling interval.
Method 2: After calling registerAudioFrameObserver to register the audio frame observer object, set the audio data format in the return value of the getObservedAudioFramePosition callback. The SDK then calculates the sampling interval according to the return value of the getPlaybackAudioParams callback, and triggers the onPlaybackAudioFrame callback according to the sampling interval.

Note:

The priority of method 1 is higher than that of method 2. If method 1 is used to set the audio data format, the setting of method 2 is invalid.

Parameters

audioFrame: The raw audio data. See AudioFrame.
channelId: The channel ID.

Returns

Without practical meaning.

onRecordAudioFrame

Gets the captured audio frame.

virtual bool onRecordAudioFrame(const char* channelId, AudioFrame& audioFrame) = 0;

To ensure that the format of the cpatured audio frame is as expected, you can choose one of the following two methods to set the audio data format:

Method 1: After calling setRecordingAudioFrameParameters to set the audio data format and registerAudioFrameObserver to register the audio frame observer object, the SDK calculates the sampling interval according to the parameters set in the methods, and triggers the onRecordAudioFrame callback according to the sampling interval.
Method 2: After calling registerAudioFrameObserver to register the audio frame observer object, set the audio data format in the return value of the getObservedAudioFramePosition callback. The SDK then calculates the sampling interval according to the return value of the getRecordAudioParams callback, and triggers the onRecordAudioFrame callback according to the sampling interval.

Note:

The priority of method 1 is higher than that of method 2. If method 1 is used to set the audio data format, the setting of method 2 is invalid.

Parameters

audioFrame: The raw audio data. See AudioFrame.
channelId: The channel ID.

Returns

Without practical meaning.

getObservedAudioFramePosition

Sets the frame position for the video observer.

virtual int getObservedAudioFramePosition() = 0;

After successfully registering the audio data observer, the SDK uses this callback for each specific audio frame processing node to determine whether to trigger the following callbacks:

You can set one or more positions you need to observe by modifying the return value of getObservedAudioFramePosition based on your scenario requirements:

When the annotation observes multiple locations, the | (or operator) is required. To conserve system resources, you can reduce the number of frame positions that you want to observe.

Returns

Returns a bitmask that sets the observation position, with the following values:

AUDIO_FRAME_POSITION_PLAYBACK(0x0001): This position can observe the playback audio mixed by all remote users, corresponding to the onPlaybackAudioFrame callback.
AUDIO_FRAME_POSITION_RECORD(0x0002): This position can observe the collected local user's audio, corresponding to the onRecordAudioFrame callback.
AUDIO_FRAME_POSITION_MIXED(0x0004): This position can observe the playback audio mixed by the loacl user and all remote users, corresponding to the onMixedAudioFrame callback.
AUDIO_FRAME_POSITION_BEFORE_MIXING(0x0008): This position can observe the audio of a single remote user before mixing, corresponding to the onPlaybackAudioFrameBeforeMixing callback.
AUDIO_FRAME_POSITION_EAR_MONITORING(0x0010): This position can observe the in-ear monitoring audio of the local user, corresponding to the onEarMonitoringAudioFrame callback.

getRecordAudioParams

Sets the audio format for the onRecordAudioFrame callback.

virtual AudioParams getRecordAudioParams() = 0;

You need to register the callback when calling the registerAudioFrameObserver method. After you successfully register the audio observer, the SDK triggers this callback, and you can set the audio format in the return value of this callback.

Attention:

The SDK triggers the onRecordAudioFrame callback with the AudioParams calculated sampling interval you set in the return value. The calculation formula is Sample interval (sec) = samplePerCall/(sampleRate × channel).

Ensure that the sample interval ≥ 0.01 (s).

Returns

The captured audio data, see AudioParams.

getMixedAudioParams

Sets the audio format for the onMixedAudioFrame callback.

virtual AudioParams getMixedAudioParams() = 0;

You need to register the callback when calling the registerAudioFrameObserver method. After you successfully register the audio observer, the SDK triggers this callback, and you can set the audio format in the return value of this callback.

Attention:

The SDK triggers the onMixedAudioFrame callback with the AudioParams calculated sampling interval you set in the return value. The calculation formula is Sample interval (sec) = samplePerCall/(sampleRate × channel).

Ensure that the sample interval ≥ 0.01 (s).

Returns

The mixed captured and playback audio data. See AudioParams.

getPlaybackAudioParams

Sets the audio format for the onPlaybackAudioFrame callback.

virtual AudioParams getPlaybackAudioParams() = 0;

You need to register the callback when calling the registerAudioFrameObserver method. After you successfully register the audio observer, the SDK triggers this callback, and you can set the audio format in the return value of this callback.

Attention:

The SDK triggers the onPlaybackAudioFrame callback with the AudioParams calculated sampling interval you set in the return value. The calculation formula is Sample interval (sec) = samplePerCall/(sampleRate × channel).

Ensure that the sample interval ≥ 0.01 (s).

Returns

The audio data for playback, see AudioParams.

getEarMonitoringAudioParams

Sets the audio format for the onEarMonitoringAudioFrame callback.

virtual AudioParams getEarMonitoringAudioParams() = 0;

Since: v4.0.1

You need to register the callback when calling the registerAudioFrameObserver method. After you successfully register the audio observer, the SDK triggers this callback, and you can set the audio format in the return value of this callback.

Attention:

The SDK triggers the onEarMonitoringAudioFrame callback with the AudioParams calculated sampling interval you set in the return value. The calculation formula is Sample interval (sec) = samplePerCall/(sampleRate × channel).

Ensure that the sample interval ≥ 0.01 (s).

Returns

The audio data of in-ear monitoring, see AudioParams.