Why does iOS CIFilter filter filter images so slowly?

  ios, question

I jumped over a page and waited for at least 3 seconds to check and step on it. I found out that because the page was filtering the image, what method can I use to increase the speed?

GPUImagePerhaps it will be faster. the following is a filter I tested with CIFilter. it took me 2 seconds.

NSLog(@"start");
 CIContext *context = [CIContext contextWithOptions:nil];
 CIImage *image = [CIImage imageWithContentsOfURL:[NSURL URLWithString:@"http://127.0.0.1:8000/top1.jpg"]];
 CIFilter *filter = [CIFilter filterWithName:@"CIGaussianBlur"];
 [filter setValue:image forKey:kCIInputImageKey];
 [filter setValue:@10.0f forKey: @"inputRadius"];
 CIImage *result = [filter valueForKey:kCIOutputImageKey];
 CGImageRef outImage = [context createCGImage: result fromRect:[result extent]];
 UIImage * blurImage = [UIImage imageWithCGImage:outImage];
 
 self.backgroundImageView.image=blurImage;
 
 NSLog(@"end");
 
 
 2015-09-09 16:18:22.703 test[7211:602636] start
 2015-09-09 16:18:24.470 test[7211:602636] end