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Custom Audio Capturing and Playback/

Custom Audio Capturing and Playback

This document describes how to use the TRTC SDK to implement custom audio capturing and rendering.

Custom Audio Capturing

The custom audio capturing feature of the TRTC SDK can be used in two steps: enabling the feature and sending audio frames to the SDK. For detailed directions of specific APIs, see below. We also provide API examples for different platforms:
Android
iOS
Windows

Enabling custom audio capturing

To enable the custom audio capturing feature of the TRTC SDK, you need to call the enableCustomAudioCapture API of TRTCCloud. Below is the sample code:
Android
iOS&Mac
Windows 
TRTCCloud mTRTCCloud = TRTCCloud.shareInstance();
mTRTCCloud.enableCustomAudioCapture(true);

self.trtcCloud = [TRTCCloud sharedInstance];
[self.trtcCloud enableCustomAudioCapture:YES];

liteav::ITRTCCloud* trtc_cloud = liteav::ITRTCCloud::getTRTCShareInstance();
trtc_cloud->enableCustomAudioCapture(true);


Sending custom audio frames

You can use the sendCustomAudioData API of TRTCCloud to populate the TRTC SDK with your own audio data. Below is the sample code:
Android
iOS&Mac
Windows 
TRTCCloudDef.TRTCAudioFrame trtcAudioFrame = new TRTCCloudDef.TRTCAudioFrame();
trtcAudioFrame.data = data;
trtcAudioFrame.sampleRate = sampleRate;
trtcAudioFrame.channel = channel;
trtcAudioFrame.timestamp = timestamp;
mTRTCCloud.sendCustomAudioData(trtcAudioFrame);

TRTCAudioFrame *audioFrame = [[TRTCAudioFrame alloc] init];
audioFrame.channels = audioChannels;
audioFrame.sampleRate = audioSampleRate;
audioFrame.data = pcmData;

[self.trtcCloud sendCustomAudioData:audioFrame];

liteav::TRTCAudioFrame frame;
frame.audioFormat = liteav::TRTCAudioFrameFormatPCM;
frame.length = buffer_size;
frame.data = array.data();
frame.sampleRate = 48000;
frame.channel = 1;
getTRTCShareInstance()->sendCustomAudioData(&frame);

notice
Using sendCustomAudioData may cause AEC to fail.

Getting Raw Audio Data

The audio module is a highly complex module, and the TRTC SDK needs to strictly control the capturing and playback logic of audio devices. In some cases, to get the audio data of a remote user or audio captured by the local mic, you can use the APIs of TRTCCloud for different platforms. We also provide API examples for those platforms:
Android:
iOS
Windows

Setting audio callback

Android
iOS&Mac
Windows
mTRTCCloud.setAudioFrameListener(new TRTCCloudListener.TRTCAudioFrameListener() {
        @Override
        public void onCapturedRawAudioFrame(TRTCCloudDef.TRTCAudioFrame trtcAudioFrame) {

        }

        @Override
        public void onLocalProcessedAudioFrame(TRTCCloudDef.TRTCAudioFrame trtcAudioFrame) {

        }

        @Override
        public void onRemoteUserAudioFrame(TRTCCloudDef.TRTCAudioFrame trtcAudioFrame, String s) {

        }

        @Override
        public void onMixedPlayAudioFrame(TRTCCloudDef.TRTCAudioFrame trtcAudioFrame) {

        }

        @Override
        public void onMixedAllAudioFrame(TRTCCloudDef.TRTCAudioFrame trtcAudioFrame) {
            // For more information, see the custom rendering tool class `com.tencent.trtc.mediashare.helper.CustomFrameRender` in `TRTC-API-Example`  
        }
    }); 

 [self.trtcCloud setAudioFrameDelegate:self];
 // MARK: - TRTCAudioFrameDelegate
 - (void)onCapturedRawAudioFrame:(TRTCAudioFrame *)frame {
        NSLog(@"onCapturedRawAudioFrame");
}

- (void)onLocalProcessedAudioFrame:(TRTCAudioFrame *)frame {
        NSLog(@"onLocalProcessedAudioFrame");
}

- (void)onRemoteUserAudioFrame:(TRTCAudioFrame *)frame userId:(NSString *)userId {
        NSLog(@"onRemoteUserAudioFrame");
}

- (void)onMixedPlayAudioFrame:(TRTCAudioFrame *)frame {
        NSLog(@"onMixedPlayAudioFrame");
}

- (void)onMixedAllAudioFrame:(TRTCAudioFrame *)frame {
        NSLog(@"onMixedAllAudioFrame");
}

// Set custom audio data callback
liteav::ITRTCCloud* trtc_cloud = liteav::ITRTCCloud::getTRTCShareInstance();
trtc_cloud->setAudioFrameCallback(callback)

// Callback APIs for custom audio

virtual void onCapturedRawAudioFrame(TRTCAudioFrame* frame) {
}

virtual void onLocalProcessedAudioFrame(TRTCAudioFrame* frame) {
}

virtual void onPlayAudioFrame(TRTCAudioFrame* frame, const char* userId) {
}

virtual void onMixedPlayAudioFrame(TRTCAudioFrame* frame) {
}

notice
Do not perform time-consuming operations with any of the above callback functions. We recommend that you copy the data to another thread for processing to avoid AEC failure and choppy audio.
The data called back by the above callback functions can only be read and copied. Modifying the data may lead to unexpected results.