Duet recording

Supported editions

Concepts

This document uses the following key concepts. We recommend that you familiarize yourself with them: duet recording, tracks, and track layouts.

Related classes

Duet recording flow

The duet recording flow is similar to the basic recording flow. The main differences are the input and output parameters and the preview view settings.

Configure duet recording parameters

Set the duet recording parameters to initialize the duet recording instance. For more information about the parameters, see the API reference in Related classes.

Set duet recording parameters

AliyunMixMediaInfoParam *mixMediaInfo = [[AliyunMixMediaInfoParam alloc] init];
mixMediaInfo.outputSizeView = previewView;
mixMediaInfo.mixVideoInfo.filePath = mixVideoFile; // Path of the sample video

Set layout parameters

// Set the sample video window size and position: place it on the bottom layer to cover the full window.
CGFloat mixWidth = previewView.bounds.size.width;
CGFloat mixHeight = previewView.bounds.size.height;
mixMediaInfo.mixVideoInfo.frame = CGRectMake(0, 0, mixWidth, mixHeight);
mixMediaInfo.mixVideoInfo.layerLevel = 1;

// Set the recording video with an aspect ratio of 9:16 in portrait mode, a resolution of 360p, and place it in the lower-right corner, above the sample video.
CGFloat recordRatio = 9.0 / 16.0;
mixMediaInfo.recordVideoInfo.resolution = CGSizeMake(360, 360 / recordRatio); 
CGFloat recordHeight = previewView.bounds.size.height * 0.5;
CGFloat recordWidth = recordHeight * recordRatio;
mixMediaInfo.recordVideoInfo.frame = CGRectMake(previewView.bounds.size.width - recordWidth - 4.0, previewView.bounds.size.height - recordHeight - 4, recordWidth, recordHeight);
mixMediaInfo.recordVideoInfo.layerLevel = 2;

// (Optional) Set the border for the sample video.
mixMediaInfo.mixVideoInfo.borderInfo.color = UIColor.blueColor;
mixMediaInfo.mixVideoInfo.borderInfo.width = 2;
mixMediaInfo.mixVideoInfo.borderInfo.cornerRadius = 6.0;

// (Optional) Set the border for the recorded video.
mixMediaInfo.recordVideoInfo.borderInfo.color = UIColor.blueColor;
mixMediaInfo.recordVideoInfo.borderInfo.width = 1;
mixMediaInfo.recordVideoInfo.borderInfo.cornerRadius = 6.0;

Create a duet recording object

AliyunMixRecorder *_recorder = [[AliyunMixRecorder alloc] initWithMediaInfo:mixMediaInfo outputSize:CGSizeMake(720, 720)];
_recorder.outputType = AliyunIRecorderVideoOutputPixelFormatType420f;
_recorder.useFaceDetect = YES;
_recorder.faceDetectCount = 2;
_recorder.faceDectectSync = NO;
_recorder.frontCaptureSessionPreset = AVCaptureSessionPreset1280x720;
_recorder.GOP = 250;
_recorder.videoQuality = AliyunVideoQualityHight;
_recorder.recordFps = 30;
_recorder.outputPath = [taskPath stringByAppendingPathComponent:@"output.mp4"];
_recorder.cameraRotate = 0;
_recorder.beautifyStatus = YES;
_recorder.frontCameraSupportVideoZoomFactor = YES;

self.aliyunMixRecorder = _recorder;

// We recommend that you set the maximum duet recording duration to be the same as the sample video duration. When the maximum duration is reached, the recorderDidStopWithMaxDuration callback is triggered.
AVURLAsset *asset = [AVURLAsset assetWithURL:[NSURL fileURLWithPath:[self resourcePath:mixVideoPath]]];
[self.aliyunMixRecorder setRecordMaxDuration:asset.aliyunVideoDuration];
[self.aliyunMixRecorder setRecordMinDuration:1.0];

// Set the duet background color.
[self.aliyunMixRecorder setBackgroundColor:0xFF0100];

// Set the duet background image.
NSString *imgPath = [self.class resourcePath:@"pig.jpeg"];
[self.aliyunMixRecorder setBackgroundImageFilePath:imgPath imageDisplayMode:AliyunMixVideoBackgroundImageModeScaleAspectFit];

Set the output audio

// Set the hardware echo cancellation effect. The Hardware mode is recommended.
self.aliyunMixRecorder.recorderAECType = AliyunIRecorderAECTypeHardware;

// Set the composited video to use the recorded audio track.
[self.aliyunMixRecorder setMixAudioSource:MixAudioSourceTypeBoth];
[self.aliyunMixRecorder setMixAudioOriginalWeight:50 recordWeight:50];

Configure callbacks

Set callbacks to promptly obtain the progress and status of audio and video processing. For more information about the parameters, see the API reference in Related classes.

- (void)recorderDeviceAuthorization:(AliyunIRecorderDeviceAuthor)status {
    dispatch_async(dispatch_get_main_queue(), ^{
        if (status == AliyunIRecorderDeviceAuthorAudioDenied) {
            [DeviceAuthorization openSetting:@"Microphone permission not granted."];
        } else if (status == AliyunIRecorderDeviceAuthorVideoDenied) {
            [DeviceAuthorization openSetting:@"Camera permission not granted."];
        }
    });
}

// Recording progress
- (void)recorderVideoDuration:(CGFloat)duration {
    NSLog(@"Mix Record Video Duration: %f", duration);
}

// A recording segment has stopped.
- (void)recorderDidStopRecording {
    NSLog(@"Mix Record Stop Recording");
}

// Recording stopped after reaching the maximum duration. You can now finish the recording.
- (void)recorderDidStopWithMaxDuration {
    NSLog(@"Mix Record Stop Recording With Max Duration");
    [self.aliyunMixRecorder finishRecording]; // Finish recording.
}

// Recording finished.
- (void)recorderDidFinishRecording {
    NSLog(@"Mix Record Did Finish Recording");
}

// Duet composition completed.
- (void)mixRecorderComposerDidComplete {
    NSLog(@"Mix Record Complete");
    [[MBProgressHUD HUDForView:self.view] hideAnimated:YES];
}

// An error occurred during composition.
- (void)mixRecorderComposerDidError:(int)errorCode {
    NSLog(@"Mix Record Error");
    [[MBProgressHUD HUDForView:self.view] hideAnimated:YES];
}

// Duet composition started.
- (void)mixRecorderComposerDidStart {
    NSLog(@"Mix Record Start");
    MBProgressHUD *hud = [MBProgressHUD showHUDAddedTo:self.view animated:YES];
    hud.mode = MBProgressHUDModeDeterminate;
    hud.removeFromSuperViewOnHide = YES;
    hud.label.text = @"Compositing...";
}

// Duet composition progress.
- (void)mixRecorderComposerOnProgress:(CGFloat)progress {
    NSLog(@"Mix Record Progress: %f", progress);
    MBProgressHUD *hub = [MBProgressHUD HUDForView:self.view];
    hub.progress = progress / self.aliyunMixRecorder.recordDuration;
}

Control preview

For more information about the parameters, see the API reference in Related classes.

// Start the preview.
[self.aliyunMixRecorder startPreviewWithPositon:AliyunIRecorderCameraPositionFront];

// Stop the preview. This is usually called after recording is finished.
[self.aliyunMixRecorder stopPreview];

Start recording

`startRecording` and `stopRecording` must be called in pairs. You can call them one or more times. The SDK generates one or more temporary video clips accordingly. For more information about the parameters, see the API reference in Related classes.

// Start recording a video clip.
[self.aliyunMixRecorder startRecording];  

// Stop recording a video clip.
[self.aliyunMixRecorder stopRecording];

Finish recording

After recording is complete, call the finishRecording API to composite the two videos. For more information about the parameters, see the API reference in Related classes.

// Finish recording and composite the two videos.
[self.aliyunMixRecorder finishRecording];

Other settings

Similar to basic recording, duet recording supports effects such as retouching, filters, and background music. It also supports features such as taking photos. You can use the AliyunMixRecorder class to control these settings. The APIs are similar to those for basic recording. For more information, see Basic recording.