iphone - Getting a thumbnail of a *.mov video IOS

Question

I want to get a thumbnail of videos (*.mov) which taken with iPhone/iPAD. I am trying to use AVFoundation library for this and getting this error:

couldn't generate thumbnail, error:Error Domain=AVFoundationErrorDomain Code=-11822 "Cannot Open" UserInfo=0x15d90a30 {NSLocalizedDescription=Cannot Open, NSLocalizedFailureReason=This media format is not supported.}

Code:

NSArray *paths=NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentDir=[paths objectAtIndex:0];
NSString *videoPath=[documentDir stringByAppendingPathComponent:[NSString stringWithFormat:@"videos/%@.mov",videoName]];


    AVURLAsset *asset=[[AVURLAsset alloc] initWithURL:videoPath options:nil];
    AVAssetImageGenerator *generator = [[AVAssetImageGenerator alloc] initWithAsset:asset];
    generator.appliesPreferredTrackTransform=TRUE;

    CMTime thumbTime = CMTimeMakeWithSeconds(0,30);

    AVAssetImageGeneratorCompletionHandler handler = ^(CMTime requestedTime, CGImageRef im, CMTime actualTime, AVAssetImageGeneratorResult result, NSError *error){
        if (result != AVAssetImageGeneratorSucceeded) {
            NSLog(@"couldn't generate thumbnail, error:%@", error);
        }
        self.img.image=[UIImage imageWithCGImage:im];
    };

    CGSize maxSize = CGSizeMake(320, 180);
    generator.maximumSize = maxSize;
    [generator generateCGImagesAsynchronouslyForTimes:[NSArray arrayWithObject:[NSValue valueWithCMTime:thumbTime]] completionHandler:handler];

I recorded videos with my app and want to show a thumbnail of them.

Answer 1

Here it is... (Picked up from this link- Getting video snapshot for thumbnail)

- (UIImage *)thumbnailImageFromURL:(NSURL *)videoURL {
    AVURLAsset *asset = [[AVURLAsset alloc] initWithURL: videoURL options:nil];
    AVAssetImageGenerator *generator = [[AVAssetImageGenerator alloc] initWithAsset:asset];
    NSError *err = NULL;
    CMTime requestedTime = CMTimeMake(1, 60);     // To create thumbnail image
    CGImageRef imgRef = [generator copyCGImageAtTime:requestedTime actualTime:NULL error:&err];
    NSLog(@"err = %@, imageRef = %@", err, imgRef);

    UIImage *thumbnailImage = [[UIImage alloc] initWithCGImage:imgRef];
    CGImageRelease(imgRef);    // MUST release explicitly to avoid memory leak

    return thumbnailImage;
}