Duet - 并排合并2个视频

Question

注意： - 并排合并视频而不会丢失视频质量

我认为这是一个非常非常重要的问题，经过大量的搜索和谷歌搜索，没有找到任何与本课题相关的有用材料。

我正在开发一个项目，我需要在一个文件中并排合并视频。

我使用AVFoundation完成了合并视频但问题是FIRST视频显示为覆盖到第二个视频（不像SMULE应用程序/卡拉OK应用程序或Tiktok应用程序那样正确合并）。

func mergeVideosFilesWithUrl(savedVideoUrl: URL, newVideoUrl: URL, audioUrl:URL)
    {
        let savePathUrl : NSURL = NSURL(fileURLWithPath: NSHomeDirectory() + "/Documents/camRecordedVideo.mp4")
        do { // delete old video
            try FileManager.default.removeItem(at: savePathUrl as URL)
        } catch { print(error.localizedDescription) }

        var mutableVideoComposition : AVMutableVideoComposition = AVMutableVideoComposition()
        var mixComposition : AVMutableComposition = AVMutableComposition()

        let aNewVideoAsset : AVAsset = AVAsset(url: newVideoUrl)
        let asavedVideoAsset : AVAsset = AVAsset(url: savedVideoUrl)

        let aNewVideoTrack : AVAssetTrack = aNewVideoAsset.tracks(withMediaType: AVMediaType.video)[0]
        let aSavedVideoTrack : AVAssetTrack = asavedVideoAsset.tracks(withMediaType: AVMediaType.video)[0]

        let mutableCompositionNewVideoTrack : AVMutableCompositionTrack = mixComposition.addMutableTrack(withMediaType: AVMediaType.video, preferredTrackID: kCMPersistentTrackID_Invalid)!
        do{
            try mutableCompositionNewVideoTrack.insertTimeRange(CMTimeRangeMake(start: CMTime.zero, duration: aNewVideoAsset.duration), of: aNewVideoTrack, at: CMTime.zero)
        }catch {  print("Mutable Error") }

        let mutableCompositionSavedVideoTrack : AVMutableCompositionTrack = mixComposition.addMutableTrack(withMediaType: AVMediaType.video, preferredTrackID: kCMPersistentTrackID_Invalid)!
        do{
            try mutableCompositionSavedVideoTrack.insertTimeRange(CMTimeRangeMake(start: CMTime.zero, duration: asavedVideoAsset.duration), of: aSavedVideoTrack , at: CMTime.zero)
        }catch{ print("Mutable Error") }

        let mainInstruction = AVMutableVideoCompositionInstruction()
        mainInstruction.timeRange = CMTimeRangeMake(start: CMTime.zero, duration: CMTimeMaximum(aNewVideoAsset.duration, asavedVideoAsset.duration) )

        let newVideoLayerInstruction = AVMutableVideoCompositionLayerInstruction(assetTrack: mutableCompositionNewVideoTrack)
        let newScale : CGAffineTransform = CGAffineTransform.init(scaleX: 0.7, y: 0.7)
        let newMove : CGAffineTransform = CGAffineTransform.init(translationX: 230, y: 230)
        newVideoLayerInstruction.setTransform(newScale.concatenating(newMove), at: CMTime.zero)

        let savedVideoLayerInstruction = AVMutableVideoCompositionLayerInstruction(assetTrack: mutableCompositionSavedVideoTrack)
        let savedScale : CGAffineTransform = CGAffineTransform.init(scaleX: 1.2, y: 1.5)
        let savedMove : CGAffineTransform = CGAffineTransform.init(translationX: 0, y: 0)
        savedVideoLayerInstruction.setTransform(savedScale.concatenating(savedMove), at: CMTime.zero)

        mainInstruction.layerInstructions = [newVideoLayerInstruction, savedVideoLayerInstruction]


        mutableVideoComposition.instructions = [mainInstruction]
        mutableVideoComposition.frameDuration = CMTimeMake(value: 1, timescale: 30)
        mutableVideoComposition.renderSize = CGSize(width: 1240 , height: self.camPreview.frame.height)

        finalPath = savePathUrl.absoluteString
        let assetExport: AVAssetExportSession = AVAssetExportSession(asset: mixComposition, presetName: AVAssetExportPresetHighestQuality)!
        assetExport.videoComposition = mutableVideoComposition
        assetExport.outputFileType = AVFileType.mov

        assetExport.outputURL = savePathUrl as URL
        assetExport.shouldOptimizeForNetworkUse = true

        assetExport.exportAsynchronously { () -> Void in
            switch assetExport.status {

            case AVAssetExportSession.Status.completed:
                print("success")
            case  AVAssetExportSession.Status.failed:
                print("failed \(assetExport.error)")
            case AVAssetExportSession.Status.cancelled:
                print("cancelled \(assetExport.error)")
            default:
                print("complete")
            }
        }

    }

这是我的输出

而我想要的是什么

因为我不知道制作SIDE BY SIDE VIDEO / DUET VIDEO的最佳方法是什么......至于现在，我使用过AVFoundation。我没有使用任何第三方框架或任何POD。

我想问一下，实施这个的最佳方法是什么？视频应该在服务器端还是应用程序上合并？我应该使用哪种方法？

任何帮助都将受到高度赞赏。谢谢

Answer 1

为了实现这一点，我将创建一个包含2个轨道的新AVMutableComposition对象，并在每个轨道上设置变换以将它们并排放置：

let composition = AVMutableComposition(urlAssetInitializationOptions: <your options>)
let videoTrackA = composition.addMutableTrack(withMediaType:.video, preferredTrackID:kCMPersistentTrackID_Invalid);
let videoTrackB = composition.addMutableTrack(withMediaType:.video, preferredTrackID:kCMPersistentTrackID_Invalid);

videoTrackA.preferredTransform = CGAffineTransform(translationX: <yourX_for_A>, y:0.0)
videoTrackB.preferredTransform = CGAffineTransform(translationX: <yourX_for_B>, y:0.0)

然后。保存使用：

let exporter = AVAssetExportSession(asset:<yourAsset>, presetName:<yourPresetName>)
exporter.exportAsynchronously(completionHandler: <yourCompletionHandler>)

（未测试Swift代码）。

Answer 2

事实上，AVAssetExportSession是出于简单的需求，而且对你的情况来说太简单了。

你必须使用AVAssetWriter。

你将AVAssetWriterInput添加到你的AVAssetWriter。

您可以使用qazxsw poi属性配置qazxsw poi的变换。

然后，使用AVAssetWriterInput调用向CMSampleBuffer（每个图像缓冲区）提供transform。

有关详细示例，请参阅完整的Apple文档：AVAssetWriterInput