Question

我正在使用以下代码从视频URL生成框架。这段代码在以前的某个时候运行良好。目前无法正常运作。抛出错误，它无法解码，并且文件可能已损坏。有人可以帮忙吗？

func previewImageFromVideo(url: NSURL) -> UIImage? {
        let url = url as URL
        let request = URLRequest(url: url)
        let cache = URLCache.shared

        if
            let cachedResponse = cache.cachedResponse(for: request),
            let image = UIImage(data: cachedResponse.data)
        {
            return image
        }

        let asset = AVAsset(url: url)
        let imageGenerator = AVAssetImageGenerator(asset: asset)
        imageGenerator.appliesPreferredTrackTransform = true
        imageGenerator.maximumSize = CGSize(width: 250, height: 120)

        var time = asset.duration
        time.value = min(time.value, 2)

        var image: UIImage?

        do {
            let cgImage = try imageGenerator.copyCGImage(at: time, actualTime: nil)
            image = UIImage(cgImage: cgImage)
        } catch { }

        if
            let image = image,
            let data = UIImagePNGRepresentation(image),
            let response = HTTPURLResponse(url: url, statusCode: 200, httpVersion: nil, headerFields: nil)
        {
            let cachedResponse = CachedURLResponse(response: response, data: data)

            cache.storeCachedResponse(cachedResponse, for: request)
        }

        return image
    }

此代码在从URL视频捕获帧时引发错误。它说文件可能已损坏。

Answer 1

我在Playground上尝试了您的代码，它运行完美。如错误消息所述，该文件可能已损坏。

const fs = require('fs');
const parse = require('node-html-parser').parse;

fs.readFile('index.html', 'utf8', (err,html)=>{
   if(err){
      throw err;
   }

   const root = parse(html);

   const body = root.querySelector('body');
   //body.set_content('<div id = "asdf"></div>');
   body.appendChild('<div id = "asdf"></div>');

   console.log(root.toString()); // This you can write back to file!
 });

无法从iOS 13中的网址视频生成缩略图

1 个答案: