SVM model training and classification return error

ZJD · June 15, 2024, 11:56am

SVM model training and classification return error

opened 10:37AM - 15 Jun 24 UTC

bug

### System Information OpenCV version: 4.10.0 Operating System:win10 Compil…er & compiler version: VS2022 ### Detailed description An exception was raised: read access permission conflict. SVM. * * Ptr * * is nullptr. ![image](https://github.com/opencv/opencv/assets/29767049/aab6ff52-ed34-4810-a86d-e2388c430564) ### Steps to reproduce ``` #include <stdio.h> #include <time.h> #include <opencv2/opencv.hpp> #include <iostream> #include <opencv2/core/core.hpp> #include <opencv2/highgui/highgui.hpp> #include <opencv2/ml/ml.hpp> #include <io.h> #include <vector> #include <string> #include <filesystem> using namespace std; using namespace cv; namespace fs = std::filesystem; void getFiles(std::string& path, vector<string>& files) { for (const auto& entry : fs::directory_iterator(path)) { if (entry.is_regular_file()) { files.push_back(entry.path().string()); } } } int main() { int result = 0; string filePath = "D:\\vcworkspace\\digits_svm\\digits_svm\\data\\test_image\\0"; vector<string> files; getFiles(filePath, files); int number = files.size(); cout << number << endl; Ptr<ml::SVM> svm; string modelpath = "digits_svm.yml"; vector<float> predictions; FileStorage svm_fs(modelpath, FileStorage::READ); if (svm_fs.isOpened()) { svm->load(modelpath.c_str()); } for (int i = 0; i < number; i++) { Mat inMat = imread(files[i].c_str()); Mat p = inMat.reshape(1, 1); p.convertTo(p, CV_32FC1); int response = (int)svm->predict(p); if (response == 0) { result++; } } cout << result << endl; getchar(); return 0; } ``` All the projects are here. https://github.com/ZJDATY/digits_svm/tree/master ### Issue submission checklist - [X] I report the issue, it's not a question - [X] I checked the problem with documentation, FAQ, open issues, forum.opencv.org, Stack Overflow, etc and have not found any solution - [X] I updated to the latest OpenCV version and the issue is still there - [X] There is reproducer code and related data files (videos, images, onnx, etc)

I have completed my training and encountered an error during the detection. Please refer to the link above for the complete situation.

An exception was raised: read access permission conflict.
SVM. * * Ptr * * is nullptr.

berak · June 15, 2024, 12:11pm

If you’re already asking here, please add code & details here, too, ty

berak · June 15, 2024, 12:16pm

or maybe even close this.
(kumataro is right, your loading code is wrong. no bug)

Topic		Replies	Views
C++error，I want to eraze this error C++	1	107	June 14, 2024
Error trying to train a cv::ml::SVMSGD: (-215:Assertion failed) responses.type() == CV_32F \|\| responses.type() == CV_32S in function 'setData' C++	3	566	September 16, 2021
Read Access Violation from opencv_cored.dll when using .converTo() C++ core	2	489	June 29, 2021
Training model to detect color instead of shape/features? AKA "Banana ripeness detector" C++ facerecognition , color , svm	0	742	January 19, 2022
Does svm->train() has a size limit? (segmentation fault) C++ svm	2	295	March 17, 2022

SVM model training and classification return error

Related topics