如何使用avfoundation合并视频剪辑？

import AVFoundation

func mergeVideoClips(videoURLs: [URL], outputURL: URL, completion: @escaping (Bool, Error?) -> Void) {
    let composition = AVMutableComposition()
    var currentTime = CMTime.zero
    
    for videoURL in videoURLs {
        let asset = AVAsset(url: videoURL)
        let assetTrack = asset.tracks(withMediaType: .video).first!
        
        let compositionTrack = composition.addMutableTrack(withMediaType: .video, preferredTrackID: kCMPersistentTrackID_Invalid)
        try! compositionTrack?.insertTimeRange(CMTimeRange(start: .zero, duration: asset.duration), of: assetTrack, at: currentTime)
        
        currentTime = CMTimeAdd(currentTime, asset.duration)
    }
    
    let videoComposition = AVMutableVideoComposition()
    videoComposition.renderSize = CGSize(width: 1280, height: 720)
    videoComposition.frameDuration = CMTime(value: 1, timescale: 30)
    
    let instruction = AVMutableVideoCompositionInstruction()
    instruction.timeRange = CMTimeRange(start: .zero, duration: currentTime)
    
    let layerInstruction = AVMutableVideoCompositionLayerInstruction(assetTrack: composition.tracks(withMediaType: .video).first!)
    instruction.layerInstructions = [layerInstruction]
    
    videoComposition.instructions = [instruction]
    
    let exportSession = AVAssetExportSession(asset: composition, presetName: AVAssetExportPresetHighestQuality)
    exportSession?.outputURL = outputURL
    exportSession?.outputFileType = .mp4
    exportSession?.videoComposition = videoComposition
    
    exportSession?.exportAsynchronously(completionHandler: {
        completion(exportSession?.status == .completed, exportSession?.error)
    })
}

// 使用示例
let videoURLs = [URL(fileURLWithPath: "video1.mp4"), URL(fileURLWithPath: "video2.mp4")]
let outputURL = URL(fileURLWithPath: "mergedVideo.mp4")

mergeVideoClips(videoURLs: videoURLs, outputURL: outputURL) { success, error in
    if success {
        print("视频合并成功")
    } else {
        print("视频合并失败：\(error?.localizedDescription ?? "")")
    }
}