iOS8之后，可以使用CIDetector(CIDetector可用于人脸识别)进行图片解析，从而使我们可以便捷的从相册中获取到二维码。
1.调用系统相册，从系统相册中选取图片
2.使用探测器(CIDetector)对选取的图片进行处理，取得图片二维码中包含的数据信息。
下面是简单的代码实现示例
- (void)choicePhoto{
//调用相册
UIImagePickerController *imagePicker = [[UIImagePickerController alloc]init];
imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
imagePicker.delegate = self;
[self presentViewController:imagePicker animated:YES completion:nil];
}
//选中图片的回调
-(void)imagePickerController:(UIImagePickerController*)picker didFinishPickingMediaWithInfo:(NSDictionary *)info{
NSString *content = @"" ;
//取出选中的图片
UIImage *pickImage = info[UIImagePickerControllerOriginalImage];
NSData *imageData = UIImagePNGRepresentation(pickImage);
CIImage *ciImage = [CIImage imageWithData:imageData];
//创建探测器
CIDetector *detector = [CIDetector detectorOfType:CIDetectorTypeQRCode context:nil options:@{CIDetectorAccuracy: CIDetectorAccuracyLow}];
NSArray *feature = [detector featuresInImage:ciImage];
//取出探测到的数据
for (CIQRCodeFeature *result in feature) {
content = result.messageString;
}//进行处理(音效、网址分析、页面跳转等)
}
