Multi-source recording

The following diagram illustrates the multi-source recording workflow:

Stage	Step	Description	Sample code
Basic	1	Create a recorder instance, configure recording parameters, and add input sources.	Initialize the recorder
	2	Start or stop the preview.	Control the preview
	3	Start or stop recording.	Start recording
	4	Finalize the recording to generate the output file.	Finish recording
Advanced	5	Configure individual input sources.	Control the camera recording source Control the screen recording source Control the local video source
	6	Configure advanced features, such as background music, speed ramping, and custom rendering.	Other features
	7	Implement recording callbacks.	Recording callbacks

Use AliyunRecorderVideoConfig to set the output video's display parameters (resolution, frame rate, rotation angle, and scaling mode) and compression parameters (encoding, GOP, bitrate, and video quality). In most cases, you do not need to configure compression parameters unless you have specific requirements.

AliyunRecorderVideoConfig *videoConfig = [[AliyunRecorderVideoConfig alloc] init];
videoConfig.resolution = CGSizeMake(720, 1280);           // 720p
videoConfig.fps = 30;
...

First, create a configuration object by using the output parameter object and outputPath. Then, add the input sources.

// Create a configuration object.
AliyunRecorderConfig *config = [[AliyunRecorderConfig alloc] initWithVideoConfig:videoConfig outputPath:[taskPath stringByAppendingPathComponent:@"output.mp4"]];


// Add a camera recording source.
// Specify the camera layout parameters.
AliyunVideoRecordLayoutParam *cameraLayout = [[AliyunVideoRecordLayoutParam alloc] initWithRenderMode:AliyunRenderMode_ResizeAspectFill];
cameraLayout.size = resolution;
cameraLayout.center = CGPointMake(resolution.width / 2.0, resolution.height / 2.0);
cameraLayout.zPosition = 1;
// Add the recording source and get its controller.
self.cameraRecorderController = [config addCamera:cameraLayout];
self.cameraRecorderController.preview = self.videoView;
self.cameraRecorderController.camera.resolution = AliyunRecordCameraResolution_3840x2160;
self.cameraRecorderController.camera.position = AVCaptureDevicePositionBack;


// Add a screen recording source.
// Specify the layout parameters for screen recording.
AliyunVideoRecordLayoutParam *viewRecordLayout = [[AliyunVideoRecordLayoutParam alloc] initWithRenderMode:AliyunRenderMode_ResizeAspect];
viewRecordLayout.size = CGSizeMake(0.5*videoConfig.resolution.width, 0.5*videoConfig.resolution.height);
viewRecordLayout.center = CGPointMake(0.5*videoConfig.resolution.width, 0.5*videoConfig.resolution.height);
viewRecordLayout.zPosition = 2;
// Specify the parameters for the screen recording source.
AliyunViewRecordSource *viewSource = [[AliyunViewRecordSource alloc] initWithTargetView:drawView fps:videoConfig.fps];
viewSource.captureInBackground = YES;
// Add the recording source and get its controller.
self.viewRecordController = [config addViewSource:viewSource layout:viewRecordLayout];


// Add a local video playback source.
// Specify the layout parameters for the local video source.
AliyunVideoRecordLayoutParam *playerRecordLayout = [[AliyunVideoRecordLayoutParam alloc] initWithRenderMode:AliyunRenderMode_ResizeAspect];
playerRecordLayout.size = CGSizeMake(0.5*videoConfig.resolution.width, 0.5*videoConfig.resolution.height);
playerRecordLayout.center = CGPointMake(0.5*videoConfig.resolution.width, 0.5*videoConfig.resolution.height);
playerRecordLayout.zPosition = 2;
// Specify the parameters for the local video playback source.
AVURLAsset *asset = [AVURLAsset URLAssetWithURL:[NSURL fileURLWithPath:videoPath] options:nil];
AliyunPlayerRecordSource *playerSource = [[AliyunPlayerRecordSource alloc] initWithAsset:asset fps:videoConfig.fps];
// Add the recording source and get its controller.
self.playerRecordController = [config addMVSource:playerSource layout:playerRecordLayout];
self.playerRecordController.preview = self.playerView;

Create an instance

// Create the recorder instance with the configuration object.
AliyunRecorder *recorder = [[AliyunRecorder alloc] initWithConfig:config];
recorder.delegate = self;
recorder.clipManager.maxDuration = 5;
recorder.clipManager.minDuration = 1;
recorder.clipManager.deleteVideoClipsOnExit = YES;
self.aliyunRecorder = recorder;

The startRecording and stopRecording methods must be called in pairs. Call these methods multiple times to generate multiple video clips. For more information about the parameters used in the code, see Related classes.

// Start recording a video clip.
[self.aliyunRecorder startRecord];  

// Stop recording a video clip. The process is not instantaneous. 
// Listen for state changes through the onAliyunRecorder:stateDidChange: callback.
[self.aliyunRecorder stopRecord];

The following table describes the recording states.

State	Description
AliyunRecorderState_Idle	The recorder is idle and waiting to start.
AliyunRecorderState_LoadingForRecord	The recorder is preparing to record. It waits for the first frame from each input source before automatically transitioning to the Recording state.
AliyunRecorderState_Recording	The recorder is actively recording.
AliyunRecorderState_Stopping	The recorder is stopping. It automatically transitions to the Stop state after internal buffers are processed.
AliyunRecorderState_Stop	The recorder is stopped.
AliyunRecorderState_Error	An error occurred. You can call cancel to reset the state to Idle.

After recording, you can either merge all clips into a single video or generate a configuration file for later editing. For more information about the parameters used in the code, see Related classes.

• finishRecord: Merges video clips into a complete video. Use this method if no further editing is required.
• finishRecordForEdit: Generates a task path for the clips without merging them. Use this method if you plan to edit the video later. You can initialize the editor with the output taskPath. For more information, see Initialize the editor.

// Finish recording and merge all clips into a single video file.
[self.aliyunRecorder finishRecord:^(NSString *outputPath, NSError *error) {
    if (!error) {
        // Recording is complete. You can preview, edit, or upload the video at outputPath.
    }
}];

// Finish recording and generate a taskPath for further editing. Clips are not merged.
[self.aliyunRecorder finishRecordForEdit:^(NSString *taskPath, NSError *error) {
    if (!error) {
        // Recording is complete. You can use taskPath to initialize the editor (AliyunEditor) 
        // for post-production. See the video editing documentation for details.
    }
}];

Common parameters

// Flashlight
self.cameraRecorderController.camera.torchMode = AVCaptureTorchModeOn;

// Camera Position
self.cameraRecorderController.camera.position = AVCaptureDevicePositionBack;

// Zoom Factor
self.cameraRecorderController.camera.videoZoomFactor = 2.0;

// Exposure Level
self.cameraRecorderController.camera.exposureValue = 0.8;

// Orientation
self.cameraRecorderController.camera.orientation = UIDeviceOrientationLandscapeLeft;

// Capture Resolution. We recommend not changing this. The SDK automatically selects a suitable
// resolution based on the output size.
self.cameraRecorderController.camera.resolution = AliyunRecordCameraResolution_1280x720;

// Flash Mode (for taking photos).
self.cameraRecorderController.camera.flashMode = AVCaptureFlashModeOn;

Border

AliyunVideoRecordBorderInfo *cameraBorder = [AliyunVideoRecordBorderInfo new];
cameraBorder.color = UIColor.whiteColor;
cameraBorder.width = 3.0;
cameraBorder.cornerRadius = 10.0;
self.cameraRecorderController.borderInfo = cameraBorder;

Basic retouching

// Enable basic retouching.
self.cameraRecorderController.beautifyStatus = YES;
self.cameraRecorderController.beautifyValue = 80;

// Disable basic retouching.
self.cameraRecorderController.beautifyStatus = NO;
self.cameraRecorderController.beautifyValue = 0;

Face stickers

// Apply a face sticker.
[self.cameraRecorderController applyFaceSticker:[self.class resourcePath:@"Gif/hanfumei-800"]];

// Apply a filter.
AliyunEffectFilter *filter = [[AliyunEffectFilter alloc] initWithFile:path];
[self.cameraRecorderController applyFilter:filter];

Animated filters

// Apply an animated filter.
NSString *filterDir = [self.class resourcePath:@"AnimationEffect/split_screen_3"];
AliyunEffectFilter *animationFilter =[[AliyunEffectFilter alloc] initWithFile:filterDir];
[self.cameraRecorderController applyAnimationFilter:animationFilter];

Static stickers

// Add a static sticker.
AliyunImageStickerController *imageController = [self.cameraRecorderController addImageSticker:imagePath];
[imageController beginEdit];
imageController.image.center = CGPointMake(150, 200);
[imageController endEdit];

You can create custom animated stickers. For more information, see animated GIF.

// Add an animated sticker.
AliyunGifStickerController * gifController = [self.cameraController addGifStickerWithConfig:[PathTool boundlePathWithPath:@"Resource/Gif/hanfumei-800"]];
[gifController beginEdit];
gifController.gif.center = CGPointMake(150, 200);
[gifController endEdit];

Take photos

// Take a photo and get the images asynchronously.
// image: The final rendered image.
// rawImage: The original captured image.
[self.cameraRecorderController takePhoto:^(UIImage *image, UIImage *rawImage) {
        
}];

Border

AliyunVideoRecordBorderInfo *border = [AliyunVideoRecordBorderInfo new];
border.color = UIColor.whiteColor;
border.width = 3.0;
border.cornerRadius = 10.0;
self.viewRecorderController.borderInfo = border;

Border

AliyunVideoRecordBorderInfo *border = [AliyunVideoRecordBorderInfo new];
border.color = UIColor.whiteColor;
border.width = 3.0;
border.cornerRadius = 10.0;
self.playerRecordController.borderInfo = border;

Use the clipManager to manage these clips, for example, by deleting the last clip or all clips. For more information about the parameters, see AliyunClipManager.

// Delete the last video clip.
[self.aliyunRecorder.clipManager deletePart];
// Delete all video clips.
[self.aliyunRecorder.clipManager deleteALLPart];

// Get the total number of clips.
[self.aliyunRecorder.clipManager partCount];

Speed ramping

// Set the recording speed. Recommended values are between 0.5 and 2.0.
[self.aliyunRecorder setRate:2];

Background music

// Add background music.
AVURLAsset *audioAsset = [AVURLAsset URLAssetWithURL:[NSURL fileURLWithPath:filePath] options:nil];
float audioDuration = CMTimeGetSeconds(audioAsset.duration);
[self.aliyunRecorder.config setBgMusicWithFile:filePath
                                startTime:0.0    // Starts from 0 seconds.
                                duration:MIN(self.aliyunRecorder.clipManager.maxDuration, audioDuration)];

// Remove the background music.
[self.aliyunRecorder.config removeBgMusic];

Watermarks

// Create a watermark.
- (AliyunRecorderImageSticker *) waterMark
{
    if (!_waterMark) {
        NSString *watermarkPath = [AlivcImage pathOfImageName:@"shortVideo_paster_gif"];
        _waterMark = [[AliyunRecorderImageSticker alloc] initWithImagePath:watermarkPath];
        _waterMark.size = CGSizeMake(42, 30);
        _waterMark.center = CGPointMake(_waterMark.size.width * 0.5 + 4, _waterMark.size.height * 0.5 + 4);
        _waterMark.autoresizingMask = UIViewAutoresizingFlexibleRightMargin | UIViewAutoresizingFlexibleBottomMargin;
    }
    return _waterMark;
}

// Apply the watermark.
[self.aliyunRecorder.config addWaterMark:self.waterMark];

// Remove the watermark.
[self.aliyunRecorder.config removeWaterMark:self.waterMark.stickerId];

Background

// Create a background object.
- (AliyunRecorderBackgroundInfo *) bgInfo
{
    if (!_bgInfo) {
        _bgInfo = [AliyunRecorderBackgroundInfo new];
         // _bgInfo.color = UIColor.redColor;
        NSString *imgName = @"xxx.png";
        _bgInfo.image = [UIImage imageNamed:imgName];
        _bgInfo.renderMode = AliyunRenderMode_ResizeAspectFill;
    }
    return _bgInfo;
}

// Apply the background object.
self.aliyunRecorder.config.bgInfo = self.bgInfo;

After adding a camera recording source, the SDK passes captured data () to your app via the customRender callback. You can then perform custom rendering, for example with a third-party SDK, and return the processed to the short video SDK for composition.

// Step 1: Enable custom rendering. A camera recording source must be added.
self.aliyunRecorder.customRender = self;
// Step 2: Implement the AliyunRecorderCustomRender protocol.
- (CVPixelBufferRef) onAliyunRecorderCustomRenderToPixelBuffer:(AliyunRecorder *)recorder withSampleBuffer:(CMSampleBufferRef)sampleBuffer {
    // Perform custom rendering here, such as integrating a third-party beauty effects SDK.
    // Return the processed CVPixelBufferRef.
    // If no custom rendering is performed, return CMSampleBufferGetImageBuffer(sampleBuffer).
    ...
}