ios - Efficient way to do series of image processing tasks serially and save them in document folder? -


i have apply 40 different image processing tasks serially on same image , save every output image in documents folder. efficient way create serial queue , call every block/method each task? fastest , efficient way it? highly appreciated. 

@property (nonatomic, strong) dispatch_queue_t effectprocessingqueue;  self.effectprocessingqueue = dispatch_queue_create("effectprocessing", dispatch_queue_serial);  dispatch_async(dispatch_get_global_queue(self.effectprocessingqueue, 0), ^(void){    //doing heavy tasks   [self task1]; }); dispatch_async(dispatch_get_global_queue(self.effectprocessingqueue, 0), ^(void){    //doing heavy tasks   [self task2]; });  .  .  .  . dispatch_async(dispatch_get_main_queue(), ^(){  //doing ui update in main thread after tasks done.  });


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