ios - 无法在 UIImagePickerController didFinishPickingMediaWithInfo : 中获取开始和结束编辑时间

Question

我使用 UIImagePickerController 来编辑和剪切视频，我这样创建它:

UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];
imagePicker.delegate = self;
[imagePicker setVideoQuality:UIImagePickerControllerQualityType640x480];
imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
imagePicker.mediaTypes = @[(__bridge NSString *)kUTTypeMovie, (__bridge NSString *)kUTTypeVideo, (__bridge NSString *)kUTTypeMPEG4];
imagePicker.allowsEditing = YES;
[self.navigationController presentViewController:imagePicker animated:YES completion:nil];

但不幸的是，在调用的委托(delegate)方法中，我无法获得开始和结束编辑时间 - 以保存编辑后的视频:

-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary<NSString *,id> *)info {

    [picker dismissViewControllerAnimated:YES completion:^{

    }];

    NSString *type = [info objectForKey:UIImagePickerControllerMediaType];
    if ([type isEqualToString:(NSString *)kUTTypeVideo] ||
        [type isEqualToString:(NSString *)kUTTypeMovie]) { // movie != video
        NSURL *videoURL = [info objectForKey:UIImagePickerControllerMediaURL];


        NSNumber *start = [info objectForKey:@"_UIImagePickerControllerVideoEditingStart"];
        NSNumber *end = [info objectForKey:@"_UIImagePickerControllerVideoEditingEnd"];

}

在我的例子中，开始和结束是零。我不知道如何获得这些信息。你能告诉我如何得到它吗？提前感谢您的帮助。

Answer 1

我只是检查你的代码并运行，我发现 _UIImagePickerControllerVideoEditingStart 和 _UIImagePickerControllerVideoEditingEnd 只返回从相机捕获的视频，但是如果你从你的 PhotoLibrary 你没有在信息字典中得到这两个键:

如果您正在使用 imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary; 那么您将获得以下信息字典日志:

    UIImagePickerControllerMediaType = "public.movie";
    UIImagePickerControllerMediaURL = "file:///private/var/mobile/Containers/Data/Application/BCBE6A30-1A92-41BB-8734-BFF052E416DE/tmp/trim.59737F15-FC2A-4EB7-89AE-DF3831089657.MOV";
    UIImagePickerControllerReferenceURL = "assets-library://asset/asset.MOV?id=87E3E50A-1DBF-449F-8BE3-AB36E718D82C&ext=MOV";

如果您正在使用 imagePicker.sourceType = UIImagePickerControllerSourceTypeCamera; 那么您将获得以下信息字典日志:

    UIImagePickerControllerMediaType = "public.movie";
    UIImagePickerControllerMediaURL = "file:///private/var/mobile/Containers/Data/Application/611D33A4-61F4-4CD0-934D-C0EFF82B75AC/tmp/capture/capturedvideo.MOV";
    "_UIImagePickerControllerVideoEditingEnd" = "2.360877976190476";
    "_UIImagePickerControllerVideoEditingStart" = "1.360505952380952";

所以在 UIImagePickerControllerSourceTypePhotoLibrary 的最后，UIImagePickerController 不会提供 _UIImagePickerControllerVideoEditingStart 和 _UIImagePickerControllerVideoEditingEnd 键。所以你可以通过使用 AVURLAsset 来获得它的持续时间，比如下面的代码，假设开始时间是 0，结束时间是完整的持续时间。

AVURLAsset *Asset = [AVURLAsset assetWithURL:videoURL];
CMTime duration = [Asset duration];
int fullduration = ceil(duration.value/duration.timescale);