MPNowPlayingInfoCenter : What is the best way to set MPMediaItemArtwork from an Url?

All methods I found to set MPMediaItemArtwork of MPNowPlayingInfoCenter are with local images. MPMediaItemArtwork *albumArt = [[MPMediaItemArtwork alloc] initWithImage: [UIImage imageNamed:@"myimage"];

But I need to set this from an imageURL

Currently i use this...

    UIImage *artworkImage = [UIImage imageWithData:[NSData dataWithContentsOfURL:[NSURL URLWithString:self.currentTrack.imageUrl]]];

    MPMediaItemArtwork *albumArt = [[MPMediaItemArtwork alloc] initWithImage: artworkImage];
    [self.payingInfoCenter setValue:albumArt forKey:MPMediaItemPropertyArtwork];

Any idea?

That's my best solution:

- (void)updateControlCenterImage:(NSURL *)imageUrl
{       
    dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
    dispatch_async(queue, ^{

            NSMutableDictionary *songInfo = [NSMutableDictionary dictionary]; 
            UIImage *artworkImage = [UIImage imageWithData:[NSData dataWithContentsOfURL:imageUrl]];
            if(artworkImage)
            {
                MPMediaItemArtwork *albumArt = [[MPMediaItemArtwork alloc] initWithImage: artworkImage];
                [songInfo setValue:albumArt forKey:MPMediaItemPropertyArtwork];
            }
           MPNowPlayingInfoCenter *infoCenter = [MPNowPlayingInfoCenter defaultCenter];
          infoCenter.nowPlayingInfo = songInfo; 
    });
}

/!\ if you've already setted the MPNowPlayingInfoCenter , get it or all other values will be overridden