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drawCountours with fixed points not working

asked 2017-04-26 03:48:31 -0500

Hello Forum,

I need to create a simple mask for an arbitrarily shaped user defined region on interest. I thought using cv::drawContours should fit my purpose. However, I am unable to run my program.

Here is the sample code:

int QtBilderkennung::simpleFunction(){

cv::Mat Image(100, 100, CV_8UC1,cv::Scalar(0)); //Create an empty Mat

std::vector<std::vector<cv::Point>> MyCont;       //Vector for user defined points
std::vector<cv::Point> MyPoint;                          //Vector for contour drawing

//Insert some points for the contour here
MyPoint.push_back(cv::Point(1, 1));
MyPoint.push_back(cv::Point(50, 50));
MyPoint.push_back(cv::Point(70, 70));
MyPoint.push_back(cv::Point(1, 1));

//Add vector with contour to MyCont

cv::Scalar color(255);
// Draw the countour
cv::drawContours(Image, MyCont, 0, color);
return 0; }

The code compiles without any problems. When I run the function it generates a std::length_error in drawContours(). Hopefully somebody can help me since I can't find anything wrong with the code.

For further intomation I am using VisualStudio 2015 and OpenCV 3.2.(x86) compiled for msvc2015.

Best regards, mouthbag

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hmm, works for me, both on linux and win(mingw). can't find anything wrong with your code.

berak gravatar imageberak ( 2017-04-26 04:04:52 -0500 )edit

1 answer

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answered 2017-04-26 05:38:53 -0500

Okay, apparently I have to wait until tomorrow to answer my own question. That's why I'm posting a comment and the official answer will follow tomorrow.

I solved the problem by looking at the OpenCV libraries I linked to my build. I was using the "release" libraries for a debug build in Visual Studio. This worked fine until now so I did not notice my mistake.

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Asked: 2017-04-26 03:48:31 -0500

Seen: 69 times

Last updated: Apr 26 '17