如何获取 AVURLAssett objective-c 的创建日期和时间

Question

我有一个应用程序，我从照片库中选择一个视频，我想从它的元数据中获取它的创建日期和时间（如果可能的话还有它的拍摄位置），以便我可以将它用于一些标签。我可以为从照片库中挑选的图像执行此操作，但它不适用于视频。这是我的图片，但我似乎无法将其改编成视频。

所以我做了一些这样的改编：

//我从图片库中获取视频

if (picker.sourceType ==UIImagePickerControllerSourceTypePhotoLibrary) {
        NSLog(@"info:%@",info);
       NSURL * movieURL = [info valueForKey:UIImagePickerControllerMediaURL] ;

 NSData * movieData = [NSData dataWithContentsOfURL:movieURL];

//我保存到documents目录，在中途获取一张图片

NSArray *documentPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
        NSString *documentsDirectory = [documentPaths objectAtIndex:0];
        NSString *slash = [documentsDirectory stringByAppendingPathComponent:@"/"];
        NSString *documentsDirectory2 = [slash stringByAppendingPathComponent:self.user.text];
        NSString *documentsDirectory21 = [documentsDirectory2 stringByAppendingPathComponent:@"/Movie"];
        if (![[NSFileManager defaultManager] fileExistsAtPath:documentsDirectory21])
            [[NSFileManager defaultManager] createDirectoryAtPath:documentsDirectory21 withIntermediateDirectories:NO attributes:nil error:&error];
        NSString *fullPath = [documentsDirectory21 stringByAppendingPathComponent:[[self imageNameTextField]text]];
        fullPath = [fullPath stringByAppendingFormat:@".mp4"];
        [ movieData writeToFile:fullPath atomically:YES];
        
        
        AVURLAsset *anAsset = [[AVURLAsset alloc] initWithURL:movieURL options:nil];

//这是我改的

    PHAsset *theAsset = [info valueForKey:UIImagePickerControllerMediaURL] ;
    
    NSLog(@"creationDate1:%@",theAsset);
    NSLog(@"creationDate2:%@",anAsset.creationDate.value);
  
    NSDate *creationDate =(NSDate *)anAsset.creationDate.value;
    NSDateFormatter *dateFormatter=[[NSDateFormatter alloc] init];
    [dateFormatter setDateFormat:@"MMMM-dd-yyyy"];
    dayString = [dateFormatter stringFromDate:creationDate];
    NSDateFormatter *dateFormatter2=[[NSDateFormatter alloc] init];
    [dateFormatter2 setDateFormat:@"hh:mm a"];
    timeString = [dateFormatter2 stringFromDate:creationDate];

if ([[anAsset tracksWithMediaType:AVMediaTypeVideo] count] > 0) {
            
            AVAssetImageGenerator *imageGenerator =
            [AVAssetImageGenerator assetImageGeneratorWithAsset:anAsset];
            Float64 durationSeconds = CMTimeGetSeconds([anAsset duration]);
           
            CMTime midpoint = CMTimeMakeWithSeconds(durationSeconds/2.0, 600);
            NSError *error;
            CMTime actualTime;
            
            CGImageRef halfWayImage = [imageGenerator copyCGImageAtTime:midpoint actualTime:&actualTime error:&error];
           
            if (halfWayImage != NULL) {
                
                NSString *actualTimeString = (NSString *)CFBridgingRelease(CMTimeCopyDescription(NULL, actualTime));
                NSString *requestedTimeString = (NSString *)CFBridgingRelease(CMTimeCopyDescription(NULL, midpoint));
                NSLog(@"Got halfWayImage: Asked for %@, got %@", requestedTimeString, actualTimeString);
                
                myImage.image = [UIImage imageWithCGImage:halfWayImage scale:1.0 orientation:UIImageOrientationRight];
                // Do something interesting with the image.
                CGImageRelease(halfWayImage);
                
            }
        }

丢弃之前我在这里拥有的东西。

Answer 1

所以我终于弄明白了。通过在

之后放置以下代码

AVURLAsset *anAsset = [[AVURLAsset alloc] initWithURL:movieURL options:nil];

PHAsset *theAsset = [信息 valueForKey:UIImagePickerControllerMediaURL] ;

NSLog(@"creationDate1:%@",theAsset);
NSLog(@"creationDate2:%@",anAsset.creationDate.value);

NSDate *creationDate =(NSDate *)anAsset.creationDate.value;
NSDateFormatter *dateFormatter=[[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"MMMM-dd-yyyy"];
dayString = [dateFormatter stringFromDate:creationDate];
NSDateFormatter *dateFormatter2=[[NSDateFormatter alloc] init];
[dateFormatter2 setDateFormat:@"hh:mm a"];
timeString = [dateFormatter2 stringFromDate:creationDate];

我已经更改了原来的 post 以反映这些更改。现在，如果我可以从资产中获取位置元数据，我就万事大吉了。

如何获取 AVURLAssett objective-c 的创建日期和时间

How do I get the creation date and time of a AVURLAssett objective-c

objective-c

ios

avurlasset

phphotolibrary