如何获取 AVURLAssett 目标 c 的创建日期和时间答案

【问题标题】：How do I get the creation date and time of a AVURLAssett objective-c如何获取 AVURLAssett 目标 c 的创建日期和时间
【发布时间】：2021-05-16 16:14:18
【问题描述】：

我有一个应用程序，我从照片库中挑选一个视频，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，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，但不适用于视频。这是我的图像，但我似乎无法将其改编为视频。

所以我做了一些这样的改编：

//我从照片库中获取视频

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

 NSData * movieData = [NSData dataWithContentsOfURL:movieURL];

//我把它保存到documentsDirectory，在中途点得到一张图片

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);
                
            }
        }

我丢弃之前在这里拥有的东西。

【问题讨论】：

标签： ios objective-c phphotolibrary avurlasset

【解决方案1】：

所以我终于想通了。通过将以下代码放在后面

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

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];

我已经更改了我原来的帖子以反映这些更改。现在，如果我能从资产中获取位置元数据，我就准备好了。

【讨论】：