Data contentsOf return nil for URL from AVURLAsset

Question

I wonder why the contentsOf returns nil for URL from AVURLAsset. After picking from the custom library with Photos framework, I tried to request the asset from PHAsset like the following:

PHCachingImageManager().requestAVAsset(forVideo: asset, options: nil) { (avAsset, _, _) in
 DispatchQueue.main.async {
 guard let asset = avAsset as? AVURLAsset else {
     return
 }
 print(asset.url) // file:///var/mobile/Media/DCIM/101APPLE/IMG_1513.MP4
  }
}

The video with the URL above can be displayed normally with AVPlayer. But when I try to get the data associated with the url using:

 do {
   let videoData = try Data(contentsOf: mediaURL!)
 } catch (let error){
     print(error.localizedDescription ?? "") // "The file “IMG_1490.MP4” couldn’t be opened because you don’t have permission to view it."
 }

Thanks for the suggestion, it says that I don't have the permission to open it, let me update the question — Kesong Xie, Feb 05 '18 at 04:26
Can you please tell me which custom library you are using to get PHAsset and are you getting proper PHAsset from that library ? — , Feb 05 '18 at 07:28

score 0 · Answer 1 · answered Feb 06 '18 at 10:27

Please find working source code in which i have retrieved recent video from gallery then i have converted that video into AVURLAsset using that AVURLAsset i converted it's data.

Swift 4

    override func viewDidLoad() {
        super.viewDidLoad()

        //For fetching Videos from Photo Library.
        let phFetchOptions = PHFetchOptions()
        phFetchOptions.sortDescriptors = [NSSortDescriptor(key: "creationDate",
                                                           ascending: false)]
        phFetchOptions.predicate = NSPredicate(format: "mediaType == %d",
                                               PHAssetMediaType.video.rawValue)
        phFetchOptions.fetchLimit = 2
        let videoPhAssetResult = PHAsset.fetchAssets(with:phFetchOptions)
        print(videoPhAssetResult.count)
        let videoPHAsset = videoPhAssetResult.object(at: 0)

        //For Fetching AvAsset from PHAsset and along with that getting Data from AvAsset
        PHCachingImageManager().requestAVAsset(forVideo:videoPHAsset , options: nil) { (vidAvAsset, _, _) in
            DispatchQueue.main.async {
                if vidAvAsset != nil {
                    let assetURL = vidAvAsset as? AVURLAsset
                    print(assetURL?.url)
                    do {
                        let videoData = try Data(contentsOf:(assetURL?.url)!)
                        print(videoData)
                    } catch (let error){
                        print(error.localizedDescription)
                    }
                }
            }

        }
    }

(Note : Please don’t forget to add Privacy - Photo Library Usage Description permission for Accessing Photo Library of Device or Simulator)

I did the same way, but the URL returns from the AVURLAsset is not accessible by using the Data constructor — Kesong Xie, Feb 07 '18 at 05:13
Please go through this source code, Incase it will find more helpful to you. https://www.dropbox.com/s/cp6882fqv62cbv3/VideoDataSO.zip?dl=0 — , Feb 07 '18 at 05:54

Data contentsOf return nil for URL from AVURLAsset

1 Answers1