swift - iOS swift : video thumbnail error

Question

我正在使用以下代码创建视频缩略图，它在大多数情况下都有效。但是有时它会抛出错误并且不会创建缩略图。我不明白为什么它有时不起作用。

这是我创建视频缩略图的方法:

let asset = AVAsset(URL: url)
let imageGenerator = AVAssetImageGenerator(asset: asset)
imageGenerator.appliesPreferredTrackTransform = true

do {
    let cgImage = try imgGenerator.copyCGImageAtTime(CMTimeMake(1, 30), actualTime: nil)
    let uiImage = UIImage(CGImage: cgImage)
    imageview.image = uiImage  
}
catch let error as NSError
{
    print("Image generation failed with error \(error)")
}

它在大多数情况下都有效，当它不起作用时会抛出此错误:

Error generating thumbnail: Error Domain=AVFoundationErrorDomain Code=-11800 "The operation could not be completed" UserInfo={NSLocalizedDescription=The operation could not be completed, NSUnderlyingError=0x17658520 {Error Domain=NSOSStatusErrorDomain Code=-12792 "(null)"}, NSLocalizedFailureReason=An unknown error occurred (-12792)}

我不知道为什么它会抛出这个错误并且没有找到任何关于堆栈溢出的解决方案，即使其他人也面临同样的问题。

Answer 1

试试这个。

func generateThumbnail(path: URL) -> UIImage? {
            do {
                let asset = AVURLAsset(url: path, options: nil)
                let imgGenerator = AVAssetImageGenerator(asset: asset)
                imgGenerator.appliesPreferredTrackTransform = true
                let cgImage = try imgGenerator.copyCGImage(at: CMTimeMake(0, 1), actualTime: nil)
                let thumbnail = UIImage(cgImage: cgImage)
                return thumbnail
            } catch let error {
                print("*** Error generating thumbnail: \(error.localizedDescription)")
                return nil
            }
        }