coredata with dispatch

gistfile1.m

- (void)saveArrayOfImages:(NSMutableArray *)arrayOfImages
{        
    for (UIImage *imageObject in arrayOfImages)
    {
        dispatch_queue_t backgroundQueue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0);
        dispatch_async(backgroundQueue, ^{
            NSManagedObjectContext *context = [appDelegate managedObjectContext];
            
            NSData *dataFromImage = UIImagePNGRepresentation(imageObject);
            
            NSManagedObject *insertObject = [NSEntityDescription insertNewObjectForEntityForName:@"Images" inManagedObjectContext:context];
            [insertObject setValue:dataFromImage forKey:@"image"];
            [appDelegate saveContext];
        });        
    }
}