如何从视频网址生成缩略图？

Question

正如this answer 中提到的，我正在使用以下代码从视频 URL 生成缩略图：

//MARK: - - Generate Thumbnail
func getThumbnailFrom(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 uiImage = UIImage.init(cgImage: cgImage)

        return uiImage


    } catch let error as NSError {

        print("Error generating thumbnail: \(error.localizedDescription)")
        return nil
    }
}

但它抛出了一个错误：

生成缩略图时出错：操作无法完成

Answer 1

使用以下代码从视频网址生成缩略图。

DispatchQueue.global().async {
    let asset = AVAsset(url: "**your url of video**")
    let assetImgGenerate : AVAssetImageGenerator = AVAssetImageGenerator(asset: asset)
     assetImgGenerate.appliesPreferredTrackTransform = true
    let time = CMTimeMake(1, 2)
    let img = try? assetImgGenerate.copyCGImage(at: time, actualTime: nil)
    if img != nil {
    let frameImg  = UIImage(cgImage: img!)
                    DispatchQueue.main.async(execute: {
    // assign your image to UIImageView
                    })
            }
    }

Answer 2

嘿，我也对视频缩略图使用了相同的逻辑。

        do {
            let videoUrl = "Url"

            let asset = AVURLAsset(url: videoUrl, options: nil)
            let imgGenerator = AVAssetImageGenerator(asset: asset)

            let cgImage = try imgGenerator.copyCGImage(at: CMTimeMake(0, 1), actualTime: nil)

            // Rotate image before proceeding
            let uiImage = UIImage(cgImage: cgImage, scale: CGFloat(1.0), orientation: .right)

            image = uiImage

        } catch let error as NSError {

            print("Error occurred: \(error)")
        }

它对我有用。得到CGImage 后，图像方向不正确，因此方向正确。看看它是否适合你。