[移动开发]【iOS】识别相册中的二维码

1、选择图片

	UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];
    imagePicker.sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;
    imagePicker.delegate = self;
    [viewController presentViewController:imagePicker animated:YES completion:nil];

2、识别图片

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary<UIImagePickerControllerInfoKey,id> *)info
{
    [picker dismissViewControllerAnimated:YES completion:nil];
    
    // 1、提取图片
    UIImage *image = info[UIImagePickerControllerOriginalImage];
    // 2、创建 CIImage
    CIImage *ciimage = [[CIImage alloc] initWithImage:image];
    // 3、识别精度
    NSDictionary *options = @{CIDetectorAccuracy: CIDetectorAccuracyHigh};
    // 4、创建识别器
    CIDetector *detector = [CIDetector detectorOfType:CIDetectorTypeQRCode context:nil options:options];
    
    NSArray *features = [detector featuresInImage:ciimage];
    
    NSString *message = nil;
    for (CIFeature *item in features) {
        if ([item isKindOfClass:[CIQRCodeFeature class]]) {
            message = [(CIQRCodeFeature *)item messageString];
            break;
        }
    }
    
    if ([self.delegate respondsToSelector:@selector(recognitionString:)]) {
        [self.delegate recognitionString:message];
    }
}

参考：iOS开发教程之识别图片中二维码功能的实现