[AVAssetExportSession在IOS 13上失败，将音频和视频混合在一起

Question

此代码在所有IOS 13之前的设备上都有效（并且仍然有效）。目前，在exportAsynchronously调用运行后出现此错误：

Error Domain = AVFoundationErrorDomain代码= -11800“该操作可能未完成” UserInfo = {NSLocalizedFailureReason =未知错误发生（-12735），NSLocalizedDescription =无法执行该操作已完成，NSUnderlyingError = 0x282e194a0 {ErrorDomain = NSOSStatusErrorDomain代码= -12735“（null）”}}]

不确定IOS 13是否在AVAssetExportSession对象的基本设置中添加/更改了一些要求，或者是什么？可能是IOS错误吗？

---

这里是代码：

func compileAudioAndVideoToMovie(audioInputURL:URL, videoInputURL:URL) {   
        let docPath:String = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0];   
        let videoOutputURL:URL = URL(fileURLWithPath: docPath).appendingPathComponent("video.mp4");   
        do   
        {   
            try FileManager.default.removeItem(at: videoOutputURL);   
        }   
        catch {}   
        let mixComposition = AVMutableComposition();   
        let videoTrack = mixComposition.addMutableTrack(withMediaType: AVMediaType.video, preferredTrackID: kCMPersistentTrackID_Invalid);   
        let videoInputAsset = AVURLAsset(url: videoInputURL);   
        let audioTrack = mixComposition.addMutableTrack(withMediaType: AVMediaType.audio, preferredTrackID: kCMPersistentTrackID_Invalid);   
        let audioInputAsset = AVURLAsset(url: audioInputURL);   
        do   
        {   
            try videoTrack?.insertTimeRange(CMTimeRangeMake(start: CMTimeMake(value: 0, timescale: 1000), duration: CMTimeMake(value: 3000, timescale: 1000)), of: videoInputAsset.tracks(withMediaType: AVMediaType.video)[0], at: CMTimeMake(value: 0, timescale: 1000));// Insert an 3-second video clip into the video track   
            try audioTrack?.insertTimeRange(CMTimeRangeMake(start: CMTimeMake(value: 0, timescale: 1000), duration: CMTimeMake(value: 3000, timescale: 1000)), of: audioInputAsset.tracks(withMediaType: AVMediaType.audio)[0], at: CMTimeMake(value: 0, timescale: 1000));// Insert an 3-second audio clip into the audio track   

            let assetExporter = AVAssetExportSession(asset: mixComposition, presetName: AVAssetExportPresetPassthrough);   
            assetExporter?.outputFileType = AVFileType.mp4;   
            assetExporter?.outputURL = videoOutputURL;   
            assetExporter?.shouldOptimizeForNetworkUse = false;   
            assetExporter?.exportAsynchronously {   
                switch (assetExporter?.status)   
                {   
                case .cancelled:   
                    print("Exporting cancelled");   
                case .completed:   
                    print("Exporting completed");   
                case .exporting:   
                    print("Exporting ...");   
                case .failed:   
                    print("Exporting failed");   
                default:   
                    print("Exporting with other result");   
                }   
                if let error = assetExporter?.error   
                {   
                    print("Error:\n\(error)");   
                }   
            }   
        }   
        catch   
        {   
            print("Exception when compiling movie");   
        }   
    }   

Answer 1

问题似乎与AVAssetExportPresetPassthrough有关（可能与处理AAC的组合有关]

更改为AVAssetExportPresetLowQuality或AVAssetExportPresetHighestQuality，然后将视频/音频正确混合为一个。同样，这只是IOS 13问题，并且可能是错误。