我想将SurfFeatureDetector限制为一组区域(掩码).对于测试,我只定义一个掩码：
Mat srcImage; //RGB source image Mat mask = Mat::zeros(srcImage.size(),srcImage.type()); Mat roi(mask,cv::Rect(10,10,100,100)); roi = Scalar(255,255,255); SurfFeatureDetector detector(); std::vector<KeyPoint> keypoints; detector.detect(srcImage,keypoints,roi); // crash //detector.detect(srcImage,keypoints); // does not crash
当我通过“roi”作为掩码时,我得到了这个错误：
OpenCV Error: Assertion Failed (mask.empty() || (mask.type() == CV_8UC1 && mask.size() == image.size())) in detect,file /Users/ux/Downloads/OpenCV-iOS/OpenCV-iOS/../opencv-svn/modules/features2d/src/detectors.cpp,line 63
这有什么问题？如何正确地将掩码传递给SurfFeatureDetector的“detect”方法？
问候,
解决方法
关于面具的两件事.
>掩码应该是8位无符号字符的1通道矩阵,转换为opencv类型CV_8U.在您的情况下,掩码是srcImage.type()类型,它是一个3通道矩阵
>你正在将roi传递给探测器,但你应该通过面具.当你对roi进行更改时,你也在改变面具.
以下应该有效
Mat srcImage; //RGB source image Mat mask = Mat::zeros(srcImage.size(),CV_8U); // type of mask is CV_8U // roi is a sub-image of mask specified by cv::Rect object Mat roi(mask,100)); // we set elements in roi region of the mask to 255 roi = Scalar(255); SurfFeatureDetector detector(); std::vector<KeyPoint> keypoints; detector.detect(srcImage,mask); // passing `mask` as a parameter
