Convert CMSampleBuffer to .mov while broadcasting with ReplayKit

Question

Tell me please whats can be wrong with my code. I try to broadcast my screen to file(newFile.mov) and then send it with some data to server, but it doesn't save and after stop capturing, file steel empty.

This is my code from BExtensionUpload that catch broadcast and save it to file in group where i get it and send to server

import ReplayKit
class SampleHandler: RPBroadcastSampleHandler {
    let appIdentifier =         "com.group.CY"
    var videoWriterInput:       AVAssetWriterInput!
    var audioWriterInput:       AVAssetWriterInput!
    var videoWriter:            AVAssetWriter!
    var sessionAtSourceTime:    CMTime!
    var outputFileLocation:     URL?
    
    override func broadcastStarted(withSetupInfo setupInfo: [String : NSObject]?) {
        do {
            outputFileLocation = videoFileLocation()
            videoWriter = try AVAssetWriter(outputURL: outputFileLocation!, fileType: AVFileType.mov)
            
            videoWriterInput = AVAssetWriterInput(mediaType: AVMediaType.video, outputSettings: [
                AVVideoCodecKey : AVVideoCodecType.h264,
                AVVideoWidthKey : 720,
                AVVideoHeightKey : 1280,
                AVVideoCompressionPropertiesKey : [
                    AVVideoAverageBitRateKey : 2300000,
                ],
            ])
            
            videoWriterInput.expectsMediaDataInRealTime = true
            
            if videoWriter.canAdd(videoWriterInput) {
                videoWriter.add(videoWriterInput)
            } else {
                print("no input added")
            }
            
            audioWriterInput = AVAssetWriterInput(mediaType: AVMediaType.audio, outputSettings: nil)
            audioWriterInput.expectsMediaDataInRealTime = true
            
            if videoWriter.canAdd(audioWriterInput!) {
                videoWriter.add(audioWriterInput!)
            }
            
            videoWriter.startWriting()
        } catch let error {
            debugPrint(error.localizedDescription)
        }
    }
    
    override func broadcastFinished() {
        super.broadcastFinished()
        
        videoWriterInput.markAsFinished()
        videoWriter.finishWriting {
            ()
        }
    }
    
    override func processSampleBuffer(_ sampleBuffer: CMSampleBuffer, with sampleBufferType: RPSampleBufferType) {
        super.processSampleBuffer(sampleBuffer, with: sampleBufferType)            
        if writable,
            sessionAtSourceTime == nil {
            sessionAtSourceTime = CMSampleBufferGetPresentationTimeStamp(sampleBuffer)
            videoWriter.startSession(atSourceTime: sessionAtSourceTime!)
        }
        
        switch sampleBufferType {
        case .video:
            if videoWriterInput.isReadyForMoreMediaData {
                videoWriterInput.append(sampleBuffer)
            }
        case .audioApp:
            if audioWriterInput.isReadyForMoreMediaData {
                audioWriterInput?.append(sampleBuffer)
            }
        case .audioMic:
            print("mic")
        @unknown default:
            print("unknown")
        }
    }
    
    func videoFileLocation() -> URL? {
        let fileManager = FileManager.default
        
        do {
            if let container = fileManager.containerURL(forSecurityApplicationGroupIdentifier: appIdentifier) {
                let videoContainer = container.appendingPathComponent("Video")
                try? fileManager.createDirectory(at: videoContainer, withIntermediateDirectories: false, attributes: nil)
                
                let videoOutputUrl = videoContainer.appendingPathComponent("newFile").appendingPathExtension("mov")
                
                if fileManager.fileExists(atPath: videoOutputUrl.path) {
                    try fileManager.removeItem(at: videoOutputUrl)
                }
                
                fileManager.createFile(atPath: videoOutputUrl.path, contents: nil, attributes: nil)
                
                return videoOutputUrl
            }
            
        } catch {
            print(error)
        }
        
        return nil
    }
}

score 1 · Answer 1 · answered Aug 27 '20 at 07:00

This code works for me, but besides my directory in app groups, i had to use PHPhotoLibrary. App groups directory not the only way to create file, you can use any directory you want. I hope it can help someone.

import ReplayKit
import Photos

class SampleHandler: RPBroadcastSampleHandler {
    
    let appIdentifier = "group.CY"
    let fileManager = FileManager.default
    
    var videoWriterInput: AVAssetWriterInput!
    var microphoneWriterInput: AVAssetWriterInput!
    
    var videoWriter: AVAssetWriter!
    
    var sessionBeginAtSourceTime: CMTime!
    
    var isRecording = false
    
    var outputFileLocation: URL!
    
    override func broadcastStarted(withSetupInfo setupInfo: [String : NSObject]?) {
        guard !isRecording else { return }
        isRecording = true
        sessionBeginAtSourceTime = nil
        setUpWriter()
    }
    
    func setUpWriter() {
        let width = UIScreen.main.bounds.width * 2
        let height = UIScreen.main.bounds.height * 2
        
        self.outputFileLocation = videoFileLocation()
        
        // Add the video input
        videoWriter = try? AVAssetWriter.init(outputURL: self.outputFileLocation, fileType: AVFileType.mp4)
        let videoCompressionPropertys = [
            AVVideoAverageBitRateKey: width * height * 10.1
        ]
        
        let videoSettings: [String: Any] = [
            AVVideoCodecKey: AVVideoCodecType.h264,
            AVVideoWidthKey: width,
            AVVideoHeightKey: height,
            AVVideoCompressionPropertiesKey: videoCompressionPropertys
        ]
        
        videoWriterInput = AVAssetWriterInput(mediaType: AVMediaType.video, outputSettings: videoSettings)
        videoWriterInput.expectsMediaDataInRealTime = true
        
        // Add the microphone input
        var acl = AudioChannelLayout()
        memset(&acl, 0, MemoryLayout<AudioChannelLayout>.size)
        acl.mChannelLayoutTag = kAudioChannelLayoutTag_Mono;
        let audioOutputSettings: [String: Any] =
            [ AVFormatIDKey: kAudioFormatMPEG4AAC,
              AVSampleRateKey : 44100,
              AVNumberOfChannelsKey : 1,
              AVEncoderBitRateKey : 64000,
              AVChannelLayoutKey : Data(bytes: &acl, count: MemoryLayout<AudioChannelLayout>.size)]
        
        microphoneWriterInput = AVAssetWriterInput(mediaType: AVMediaType.audio, outputSettings: audioOutputSettings)
        microphoneWriterInput.expectsMediaDataInRealTime = true
        
        if videoWriter.canAdd(videoWriterInput) {
            videoWriter.add(videoWriterInput)
        }
        
        if videoWriter.canAdd(microphoneWriterInput) {
            videoWriter.add(microphoneWriterInput)
        }
        
        videoWriter.startWriting()
    }
    
    override func broadcastFinished() {
        guard isRecording else { return }
        isRecording = false
        sessionBeginAtSourceTime = nil
        
        let dispatchGroup = DispatchGroup()
        dispatchGroup.enter()
        
        videoWriterInput.markAsFinished()
        microphoneWriterInput.markAsFinished()
        
        var finishedWriting = false
        videoWriter.finishWriting {
            PHPhotoLibrary.shared().performChanges({
                PHAssetCollectionChangeRequest.creationRequestForAssetCollection(withTitle: "xxx")
                
                PHAssetChangeRequest.creationRequestForAssetFromVideo(atFileURL: self.outputFileLocation)
            }) { completed, error in
                if completed {
                    NSLog("Video \(self.outputFileLocation.path ?? "") has been moved to camera roll")
                }
                
                if error != nil {
                    NSLog("ERROR:::Cannot move the video \(self.outputFileLocation.path ?? "") to camera roll, error: \(error!.localizedDescription)")
                }
                
                finishedWriting = true
            }
            
            while finishedWriting == false {
                //          NSLog("DEBUG:::Waiting to finish writing...")
            }
            
            dispatchGroup.leave()
        }
        
        dispatchGroup.wait() // <= blocks the thread here
    }
    
    override func finishBroadcastWithError(_ error: Error) {
        let e = error
        print(e)
    }
    
    override func processSampleBuffer(_ sampleBuffer: CMSampleBuffer, with sampleBufferType: RPSampleBufferType) {
        let writable = canWrite()
        
        if writable, sessionBeginAtSourceTime == nil {
            sessionBeginAtSourceTime = CMSampleBufferGetPresentationTimeStamp(sampleBuffer)
            videoWriter.startSession(atSourceTime: sessionBeginAtSourceTime!)
        }
        
        if writable {
            switch sampleBufferType {
            case .video:
                if videoWriterInput.isReadyForMoreMediaData {
                    videoWriterInput.append(sampleBuffer)
                }
            case .audioApp:
                print("audio")
            case .audioMic:
                if microphoneWriterInput.isReadyForMoreMediaData {
                    microphoneWriterInput.append(sampleBuffer)
                }
            @unknown default:
                print("unknown")
            }
        }
    }
    
    func videoFileLocation() -> URL {
        let documentsPath = fileManager.containerURL(forSecurityApplicationGroupIdentifier: appIdentifier)!
        let videoOutputUrl = documentsPath
            .appendingPathComponent("Library")
            .appendingPathComponent("Caches")
            .appendingPathComponent("mobile")
            .appendingPathExtension("mp4")
        do {
            if fileManager.fileExists(atPath: videoOutputUrl.path) {
                try fileManager.removeItem(at: videoOutputUrl)
            }
        } catch { print(error) }
        
        return videoOutputUrl
    }
    
    func canWrite() -> Bool {
        return videoWriter != nil && isRecording && videoWriter?.status == .writing
    }
}

Convert CMSampleBuffer to .mov while broadcasting with ReplayKit

1 Answers1