iOS Swift -如何获取本地和远程视频的宽高比？

import AVFoundation

func getLocalVideoAspectRatio(url: URL) -> CGFloat? {
    let asset = AVAsset(url: url)
    let videoTrack = asset.tracks(withMediaType: .video).first
    
    if let videoSize = videoTrack?.naturalSize {
        let aspectRatio = videoSize.width / videoSize.height
        return aspectRatio
    }
    
    return nil
}

import AVFoundation

func getRemoteVideoAspectRatio(url: URL, completion: @escaping (CGFloat?) -> Void) {
    let asset = AVAsset(url: url)
    let playerItem = AVPlayerItem(asset: asset)
    let player = AVPlayer(playerItem: playerItem)
    
    player.currentItem?.asset.loadValuesAsynchronously(forKeys: ["tracks"]) {
        var aspectRatio: CGFloat?
        
        let videoTrack = playerItem.asset.tracks(withMediaType: .video).first
        if let videoSize = videoTrack?.naturalSize {
            aspectRatio = videoSize.width / videoSize.height
        }
        
        DispatchQueue.main.async {
            completion(aspectRatio)
        }
    }
}