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hello all , I am an iOS developer. I use NSData *imageData = UIImagePNGRepresentation(editedImage);     CIImage *ciImage = [CIImage imageWithData:imageData];             CIDetector *detector = [CIDetector detectorOfType:CIDetectorTypeQRCode context:nil options:@{CIDetectorAccuracy: CIDetectorAccuracyHigh}];             NSArray *feature = [detector featuresInImage:ciImage];             if (feature.count > 0) {                 CIQRCodeFeature *featureObject = [feature firstObject];                 NSString *content = featureObject.messageString; ...... ......             } else {                 [self showAlertView];             } it works well on most of QRCode. However, such as pic like this it can not find right qrcode in the pic. the NSArray feature is nil so I wonder why this happen this pic can be recognized in app like WeChat.Did I use the api not properly?